diff options
Diffstat (limited to 'drivers/android')
| -rw-r--r-- | drivers/android/Kconfig | 50 | ||||
| -rw-r--r-- | drivers/android/Makefile | 6 | ||||
| -rw-r--r-- | drivers/android/binder.c | 6616 | ||||
| -rw-r--r-- | drivers/android/binder_alloc.c | 1286 | ||||
| -rw-r--r-- | drivers/android/binder_alloc.h | 185 | ||||
| -rw-r--r-- | drivers/android/binder_alloc_selftest.c | 302 | ||||
| -rw-r--r-- | drivers/android/binder_internal.h | 561 | ||||
| -rw-r--r-- | drivers/android/binder_trace.h | 432 | ||||
| -rw-r--r-- | drivers/android/binderfs.c | 828 |
9 files changed, 10266 insertions, 0 deletions
diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig new file mode 100644 index 000000000..07aa8ae0a --- /dev/null +++ b/drivers/android/Kconfig @@ -0,0 +1,50 @@ +# SPDX-License-Identifier: GPL-2.0 +menu "Android" + +config ANDROID_BINDER_IPC + bool "Android Binder IPC Driver" + depends on MMU + default n + help + Binder is used in Android for both communication between processes, + and remote method invocation. + + This means one Android process can call a method/routine in another + Android process, using Binder to identify, invoke and pass arguments + between said processes. + +config ANDROID_BINDERFS + bool "Android Binderfs filesystem" + depends on ANDROID_BINDER_IPC + default n + help + Binderfs is a pseudo-filesystem for the Android Binder IPC driver + which can be mounted per-ipc namespace allowing to run multiple + instances of Android. + Each binderfs mount initially only contains a binder-control device. + It can be used to dynamically allocate new binder IPC devices via + ioctls. + +config ANDROID_BINDER_DEVICES + string "Android Binder devices" + depends on ANDROID_BINDER_IPC + default "binder,hwbinder,vndbinder" + help + Default value for the binder.devices parameter. + + The binder.devices parameter is a comma-separated list of strings + that specifies the names of the binder device nodes that will be + created. Each binder device has its own context manager, and is + therefore logically separated from the other devices. + +config ANDROID_BINDER_IPC_SELFTEST + bool "Android Binder IPC Driver Selftest" + depends on ANDROID_BINDER_IPC + help + This feature allows binder selftest to run. + + Binder selftest checks the allocation and free of binder buffers + exhaustively with combinations of various buffer sizes and + alignments. + +endmenu diff --git a/drivers/android/Makefile b/drivers/android/Makefile new file mode 100644 index 000000000..c9d3d0c99 --- /dev/null +++ b/drivers/android/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0-only +ccflags-y += -I$(src) # needed for trace events + +obj-$(CONFIG_ANDROID_BINDERFS) += binderfs.o +obj-$(CONFIG_ANDROID_BINDER_IPC) += binder.o binder_alloc.o +obj-$(CONFIG_ANDROID_BINDER_IPC_SELFTEST) += binder_alloc_selftest.o diff --git a/drivers/android/binder.c b/drivers/android/binder.c new file mode 100644 index 000000000..d933ef6cc --- /dev/null +++ b/drivers/android/binder.c @@ -0,0 +1,6616 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* binder.c + * + * Android IPC Subsystem + * + * Copyright (C) 2007-2008 Google, Inc. + */ + +/* + * Locking overview + * + * There are 3 main spinlocks which must be acquired in the + * order shown: + * + * 1) proc->outer_lock : protects binder_ref + * binder_proc_lock() and binder_proc_unlock() are + * used to acq/rel. + * 2) node->lock : protects most fields of binder_node. + * binder_node_lock() and binder_node_unlock() are + * used to acq/rel + * 3) proc->inner_lock : protects the thread and node lists + * (proc->threads, proc->waiting_threads, proc->nodes) + * and all todo lists associated with the binder_proc + * (proc->todo, thread->todo, proc->delivered_death and + * node->async_todo), as well as thread->transaction_stack + * binder_inner_proc_lock() and binder_inner_proc_unlock() + * are used to acq/rel + * + * Any lock under procA must never be nested under any lock at the same + * level or below on procB. + * + * Functions that require a lock held on entry indicate which lock + * in the suffix of the function name: + * + * foo_olocked() : requires node->outer_lock + * foo_nlocked() : requires node->lock + * foo_ilocked() : requires proc->inner_lock + * foo_oilocked(): requires proc->outer_lock and proc->inner_lock + * foo_nilocked(): requires node->lock and proc->inner_lock + * ... + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/fdtable.h> +#include <linux/file.h> +#include <linux/freezer.h> +#include <linux/fs.h> +#include <linux/list.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/nsproxy.h> +#include <linux/poll.h> +#include <linux/debugfs.h> +#include <linux/rbtree.h> +#include <linux/sched/signal.h> +#include <linux/sched/mm.h> +#include <linux/seq_file.h> +#include <linux/string.h> +#include <linux/uaccess.h> +#include <linux/pid_namespace.h> +#include <linux/security.h> +#include <linux/spinlock.h> +#include <linux/ratelimit.h> +#include <linux/syscalls.h> +#include <linux/task_work.h> +#include <linux/sizes.h> + +#include <uapi/linux/android/binder.h> + +#include <linux/cacheflush.h> + +#include "binder_internal.h" +#include "binder_trace.h" + +static HLIST_HEAD(binder_deferred_list); +static DEFINE_MUTEX(binder_deferred_lock); + +static HLIST_HEAD(binder_devices); +static HLIST_HEAD(binder_procs); +static DEFINE_MUTEX(binder_procs_lock); + +static HLIST_HEAD(binder_dead_nodes); +static DEFINE_SPINLOCK(binder_dead_nodes_lock); + +static struct dentry *binder_debugfs_dir_entry_root; +static struct dentry *binder_debugfs_dir_entry_proc; +static atomic_t binder_last_id; + +static int proc_show(struct seq_file *m, void *unused); +DEFINE_SHOW_ATTRIBUTE(proc); + +#define FORBIDDEN_MMAP_FLAGS (VM_WRITE) + +enum { + BINDER_DEBUG_USER_ERROR = 1U << 0, + BINDER_DEBUG_FAILED_TRANSACTION = 1U << 1, + BINDER_DEBUG_DEAD_TRANSACTION = 1U << 2, + BINDER_DEBUG_OPEN_CLOSE = 1U << 3, + BINDER_DEBUG_DEAD_BINDER = 1U << 4, + BINDER_DEBUG_DEATH_NOTIFICATION = 1U << 5, + BINDER_DEBUG_READ_WRITE = 1U << 6, + BINDER_DEBUG_USER_REFS = 1U << 7, + BINDER_DEBUG_THREADS = 1U << 8, + BINDER_DEBUG_TRANSACTION = 1U << 9, + BINDER_DEBUG_TRANSACTION_COMPLETE = 1U << 10, + BINDER_DEBUG_FREE_BUFFER = 1U << 11, + BINDER_DEBUG_INTERNAL_REFS = 1U << 12, + BINDER_DEBUG_PRIORITY_CAP = 1U << 13, + BINDER_DEBUG_SPINLOCKS = 1U << 14, +}; +static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR | + BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION; +module_param_named(debug_mask, binder_debug_mask, uint, 0644); + +char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES; +module_param_named(devices, binder_devices_param, charp, 0444); + +static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait); +static int binder_stop_on_user_error; + +static int binder_set_stop_on_user_error(const char *val, + const struct kernel_param *kp) +{ + int ret; + + ret = param_set_int(val, kp); + if (binder_stop_on_user_error < 2) + wake_up(&binder_user_error_wait); + return ret; +} +module_param_call(stop_on_user_error, binder_set_stop_on_user_error, + param_get_int, &binder_stop_on_user_error, 0644); + +static __printf(2, 3) void binder_debug(int mask, const char *format, ...) +{ + struct va_format vaf; + va_list args; + + if (binder_debug_mask & mask) { + va_start(args, format); + vaf.va = &args; + vaf.fmt = format; + pr_info_ratelimited("%pV", &vaf); + va_end(args); + } +} + +#define binder_txn_error(x...) \ + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, x) + +static __printf(1, 2) void binder_user_error(const char *format, ...) +{ + struct va_format vaf; + va_list args; + + if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) { + va_start(args, format); + vaf.va = &args; + vaf.fmt = format; + pr_info_ratelimited("%pV", &vaf); + va_end(args); + } + + if (binder_stop_on_user_error) + binder_stop_on_user_error = 2; +} + +#define binder_set_extended_error(ee, _id, _command, _param) \ + do { \ + (ee)->id = _id; \ + (ee)->command = _command; \ + (ee)->param = _param; \ + } while (0) + +#define to_flat_binder_object(hdr) \ + container_of(hdr, struct flat_binder_object, hdr) + +#define to_binder_fd_object(hdr) container_of(hdr, struct binder_fd_object, hdr) + +#define to_binder_buffer_object(hdr) \ + container_of(hdr, struct binder_buffer_object, hdr) + +#define to_binder_fd_array_object(hdr) \ + container_of(hdr, struct binder_fd_array_object, hdr) + +static struct binder_stats binder_stats; + +static inline void binder_stats_deleted(enum binder_stat_types type) +{ + atomic_inc(&binder_stats.obj_deleted[type]); +} + +static inline void binder_stats_created(enum binder_stat_types type) +{ + atomic_inc(&binder_stats.obj_created[type]); +} + +struct binder_transaction_log_entry { + int debug_id; + int debug_id_done; + int call_type; + int from_proc; + int from_thread; + int target_handle; + int to_proc; + int to_thread; + int to_node; + int data_size; + int offsets_size; + int return_error_line; + uint32_t return_error; + uint32_t return_error_param; + char context_name[BINDERFS_MAX_NAME + 1]; +}; + +struct binder_transaction_log { + atomic_t cur; + bool full; + struct binder_transaction_log_entry entry[32]; +}; + +static struct binder_transaction_log binder_transaction_log; +static struct binder_transaction_log binder_transaction_log_failed; + +static struct binder_transaction_log_entry *binder_transaction_log_add( + struct binder_transaction_log *log) +{ + struct binder_transaction_log_entry *e; + unsigned int cur = atomic_inc_return(&log->cur); + + if (cur >= ARRAY_SIZE(log->entry)) + log->full = true; + e = &log->entry[cur % ARRAY_SIZE(log->entry)]; + WRITE_ONCE(e->debug_id_done, 0); + /* + * write-barrier to synchronize access to e->debug_id_done. + * We make sure the initialized 0 value is seen before + * memset() other fields are zeroed by memset. + */ + smp_wmb(); + memset(e, 0, sizeof(*e)); + return e; +} + +enum binder_deferred_state { + BINDER_DEFERRED_FLUSH = 0x01, + BINDER_DEFERRED_RELEASE = 0x02, +}; + +enum { + BINDER_LOOPER_STATE_REGISTERED = 0x01, + BINDER_LOOPER_STATE_ENTERED = 0x02, + BINDER_LOOPER_STATE_EXITED = 0x04, + BINDER_LOOPER_STATE_INVALID = 0x08, + BINDER_LOOPER_STATE_WAITING = 0x10, + BINDER_LOOPER_STATE_POLL = 0x20, +}; + +/** + * binder_proc_lock() - Acquire outer lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Acquires proc->outer_lock. Used to protect binder_ref + * structures associated with the given proc. + */ +#define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__) +static void +_binder_proc_lock(struct binder_proc *proc, int line) + __acquires(&proc->outer_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&proc->outer_lock); +} + +/** + * binder_proc_unlock() - Release spinlock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Release lock acquired via binder_proc_lock() + */ +#define binder_proc_unlock(_proc) _binder_proc_unlock(_proc, __LINE__) +static void +_binder_proc_unlock(struct binder_proc *proc, int line) + __releases(&proc->outer_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&proc->outer_lock); +} + +/** + * binder_inner_proc_lock() - Acquire inner lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Acquires proc->inner_lock. Used to protect todo lists + */ +#define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__) +static void +_binder_inner_proc_lock(struct binder_proc *proc, int line) + __acquires(&proc->inner_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&proc->inner_lock); +} + +/** + * binder_inner_proc_unlock() - Release inner lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Release lock acquired via binder_inner_proc_lock() + */ +#define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__) +static void +_binder_inner_proc_unlock(struct binder_proc *proc, int line) + __releases(&proc->inner_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&proc->inner_lock); +} + +/** + * binder_node_lock() - Acquire spinlock for given binder_node + * @node: struct binder_node to acquire + * + * Acquires node->lock. Used to protect binder_node fields + */ +#define binder_node_lock(node) _binder_node_lock(node, __LINE__) +static void +_binder_node_lock(struct binder_node *node, int line) + __acquires(&node->lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&node->lock); +} + +/** + * binder_node_unlock() - Release spinlock for given binder_proc + * @node: struct binder_node to acquire + * + * Release lock acquired via binder_node_lock() + */ +#define binder_node_unlock(node) _binder_node_unlock(node, __LINE__) +static void +_binder_node_unlock(struct binder_node *node, int line) + __releases(&node->lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&node->lock); +} + +/** + * binder_node_inner_lock() - Acquire node and inner locks + * @node: struct binder_node to acquire + * + * Acquires node->lock. If node->proc also acquires + * proc->inner_lock. Used to protect binder_node fields + */ +#define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__) +static void +_binder_node_inner_lock(struct binder_node *node, int line) + __acquires(&node->lock) __acquires(&node->proc->inner_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&node->lock); + if (node->proc) + binder_inner_proc_lock(node->proc); + else + /* annotation for sparse */ + __acquire(&node->proc->inner_lock); +} + +/** + * binder_node_unlock() - Release node and inner locks + * @node: struct binder_node to acquire + * + * Release lock acquired via binder_node_lock() + */ +#define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__) +static void +_binder_node_inner_unlock(struct binder_node *node, int line) + __releases(&node->lock) __releases(&node->proc->inner_lock) +{ + struct binder_proc *proc = node->proc; + + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + if (proc) + binder_inner_proc_unlock(proc); + else + /* annotation for sparse */ + __release(&node->proc->inner_lock); + spin_unlock(&node->lock); +} + +static bool binder_worklist_empty_ilocked(struct list_head *list) +{ + return list_empty(list); +} + +/** + * binder_worklist_empty() - Check if no items on the work list + * @proc: binder_proc associated with list + * @list: list to check + * + * Return: true if there are no items on list, else false + */ +static bool binder_worklist_empty(struct binder_proc *proc, + struct list_head *list) +{ + bool ret; + + binder_inner_proc_lock(proc); + ret = binder_worklist_empty_ilocked(list); + binder_inner_proc_unlock(proc); + return ret; +} + +/** + * binder_enqueue_work_ilocked() - Add an item to the work list + * @work: struct binder_work to add to list + * @target_list: list to add work to + * + * Adds the work to the specified list. Asserts that work + * is not already on a list. + * + * Requires the proc->inner_lock to be held. + */ +static void +binder_enqueue_work_ilocked(struct binder_work *work, + struct list_head *target_list) +{ + BUG_ON(target_list == NULL); + BUG_ON(work->entry.next && !list_empty(&work->entry)); + list_add_tail(&work->entry, target_list); +} + +/** + * binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread. Doesn't set the process_todo + * flag, which means that (if it wasn't already set) the thread will go to + * sleep without handling this work when it calls read. + * + * Requires the proc->inner_lock to be held. + */ +static void +binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread, + struct binder_work *work) +{ + WARN_ON(!list_empty(&thread->waiting_thread_node)); + binder_enqueue_work_ilocked(work, &thread->todo); +} + +/** + * binder_enqueue_thread_work_ilocked() - Add an item to the thread work list + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread, and enables processing + * of the todo queue. + * + * Requires the proc->inner_lock to be held. + */ +static void +binder_enqueue_thread_work_ilocked(struct binder_thread *thread, + struct binder_work *work) +{ + WARN_ON(!list_empty(&thread->waiting_thread_node)); + binder_enqueue_work_ilocked(work, &thread->todo); + thread->process_todo = true; +} + +/** + * binder_enqueue_thread_work() - Add an item to the thread work list + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread, and enables processing + * of the todo queue. + */ +static void +binder_enqueue_thread_work(struct binder_thread *thread, + struct binder_work *work) +{ + binder_inner_proc_lock(thread->proc); + binder_enqueue_thread_work_ilocked(thread, work); + binder_inner_proc_unlock(thread->proc); +} + +static void +binder_dequeue_work_ilocked(struct binder_work *work) +{ + list_del_init(&work->entry); +} + +/** + * binder_dequeue_work() - Removes an item from the work list + * @proc: binder_proc associated with list + * @work: struct binder_work to remove from list + * + * Removes the specified work item from whatever list it is on. + * Can safely be called if work is not on any list. + */ +static void +binder_dequeue_work(struct binder_proc *proc, struct binder_work *work) +{ + binder_inner_proc_lock(proc); + binder_dequeue_work_ilocked(work); + binder_inner_proc_unlock(proc); +} + +static struct binder_work *binder_dequeue_work_head_ilocked( + struct list_head *list) +{ + struct binder_work *w; + + w = list_first_entry_or_null(list, struct binder_work, entry); + if (w) + list_del_init(&w->entry); + return w; +} + +static void +binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer); +static void binder_free_thread(struct binder_thread *thread); +static void binder_free_proc(struct binder_proc *proc); +static void binder_inc_node_tmpref_ilocked(struct binder_node *node); + +static bool binder_has_work_ilocked(struct binder_thread *thread, + bool do_proc_work) +{ + return thread->process_todo || + thread->looper_need_return || + (do_proc_work && + !binder_worklist_empty_ilocked(&thread->proc->todo)); +} + +static bool binder_has_work(struct binder_thread *thread, bool do_proc_work) +{ + bool has_work; + + binder_inner_proc_lock(thread->proc); + has_work = binder_has_work_ilocked(thread, do_proc_work); + binder_inner_proc_unlock(thread->proc); + + return has_work; +} + +static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread) +{ + return !thread->transaction_stack && + binder_worklist_empty_ilocked(&thread->todo) && + (thread->looper & (BINDER_LOOPER_STATE_ENTERED | + BINDER_LOOPER_STATE_REGISTERED)); +} + +static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc, + bool sync) +{ + struct rb_node *n; + struct binder_thread *thread; + + for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) { + thread = rb_entry(n, struct binder_thread, rb_node); + if (thread->looper & BINDER_LOOPER_STATE_POLL && + binder_available_for_proc_work_ilocked(thread)) { + if (sync) + wake_up_interruptible_sync(&thread->wait); + else + wake_up_interruptible(&thread->wait); + } + } +} + +/** + * binder_select_thread_ilocked() - selects a thread for doing proc work. + * @proc: process to select a thread from + * + * Note that calling this function moves the thread off the waiting_threads + * list, so it can only be woken up by the caller of this function, or a + * signal. Therefore, callers *should* always wake up the thread this function + * returns. + * + * Return: If there's a thread currently waiting for process work, + * returns that thread. Otherwise returns NULL. + */ +static struct binder_thread * +binder_select_thread_ilocked(struct binder_proc *proc) +{ + struct binder_thread *thread; + + assert_spin_locked(&proc->inner_lock); + thread = list_first_entry_or_null(&proc->waiting_threads, + struct binder_thread, + waiting_thread_node); + + if (thread) + list_del_init(&thread->waiting_thread_node); + + return thread; +} + +/** + * binder_wakeup_thread_ilocked() - wakes up a thread for doing proc work. + * @proc: process to wake up a thread in + * @thread: specific thread to wake-up (may be NULL) + * @sync: whether to do a synchronous wake-up + * + * This function wakes up a thread in the @proc process. + * The caller may provide a specific thread to wake-up in + * the @thread parameter. If @thread is NULL, this function + * will wake up threads that have called poll(). + * + * Note that for this function to work as expected, callers + * should first call binder_select_thread() to find a thread + * to handle the work (if they don't have a thread already), + * and pass the result into the @thread parameter. + */ +static void binder_wakeup_thread_ilocked(struct binder_proc *proc, + struct binder_thread *thread, + bool sync) +{ + assert_spin_locked(&proc->inner_lock); + + if (thread) { + if (sync) + wake_up_interruptible_sync(&thread->wait); + else + wake_up_interruptible(&thread->wait); + return; + } + + /* Didn't find a thread waiting for proc work; this can happen + * in two scenarios: + * 1. All threads are busy handling transactions + * In that case, one of those threads should call back into + * the kernel driver soon and pick up this work. + * 2. Threads are using the (e)poll interface, in which case + * they may be blocked on the waitqueue without having been + * added to waiting_threads. For this case, we just iterate + * over all threads not handling transaction work, and + * wake them all up. We wake all because we don't know whether + * a thread that called into (e)poll is handling non-binder + * work currently. + */ + binder_wakeup_poll_threads_ilocked(proc, sync); +} + +static void binder_wakeup_proc_ilocked(struct binder_proc *proc) +{ + struct binder_thread *thread = binder_select_thread_ilocked(proc); + + binder_wakeup_thread_ilocked(proc, thread, /* sync = */false); +} + +static void binder_set_nice(long nice) +{ + long min_nice; + + if (can_nice(current, nice)) { + set_user_nice(current, nice); + return; + } + min_nice = rlimit_to_nice(rlimit(RLIMIT_NICE)); + binder_debug(BINDER_DEBUG_PRIORITY_CAP, + "%d: nice value %ld not allowed use %ld instead\n", + current->pid, nice, min_nice); + set_user_nice(current, min_nice); + if (min_nice <= MAX_NICE) + return; + binder_user_error("%d RLIMIT_NICE not set\n", current->pid); +} + +static struct binder_node *binder_get_node_ilocked(struct binder_proc *proc, + binder_uintptr_t ptr) +{ + struct rb_node *n = proc->nodes.rb_node; + struct binder_node *node; + + assert_spin_locked(&proc->inner_lock); + + while (n) { + node = rb_entry(n, struct binder_node, rb_node); + + if (ptr < node->ptr) + n = n->rb_left; + else if (ptr > node->ptr) + n = n->rb_right; + else { + /* + * take an implicit weak reference + * to ensure node stays alive until + * call to binder_put_node() + */ + binder_inc_node_tmpref_ilocked(node); + return node; + } + } + return NULL; +} + +static struct binder_node *binder_get_node(struct binder_proc *proc, + binder_uintptr_t ptr) +{ + struct binder_node *node; + + binder_inner_proc_lock(proc); + node = binder_get_node_ilocked(proc, ptr); + binder_inner_proc_unlock(proc); + return node; +} + +static struct binder_node *binder_init_node_ilocked( + struct binder_proc *proc, + struct binder_node *new_node, + struct flat_binder_object *fp) +{ + struct rb_node **p = &proc->nodes.rb_node; + struct rb_node *parent = NULL; + struct binder_node *node; + binder_uintptr_t ptr = fp ? fp->binder : 0; + binder_uintptr_t cookie = fp ? fp->cookie : 0; + __u32 flags = fp ? fp->flags : 0; + + assert_spin_locked(&proc->inner_lock); + + while (*p) { + + parent = *p; + node = rb_entry(parent, struct binder_node, rb_node); + + if (ptr < node->ptr) + p = &(*p)->rb_left; + else if (ptr > node->ptr) + p = &(*p)->rb_right; + else { + /* + * A matching node is already in + * the rb tree. Abandon the init + * and return it. + */ + binder_inc_node_tmpref_ilocked(node); + return node; + } + } + node = new_node; + binder_stats_created(BINDER_STAT_NODE); + node->tmp_refs++; + rb_link_node(&node->rb_node, parent, p); + rb_insert_color(&node->rb_node, &proc->nodes); + node->debug_id = atomic_inc_return(&binder_last_id); + node->proc = proc; + node->ptr = ptr; + node->cookie = cookie; + node->work.type = BINDER_WORK_NODE; + node->min_priority = flags & FLAT_BINDER_FLAG_PRIORITY_MASK; + node->accept_fds = !!(flags & FLAT_BINDER_FLAG_ACCEPTS_FDS); + node->txn_security_ctx = !!(flags & FLAT_BINDER_FLAG_TXN_SECURITY_CTX); + spin_lock_init(&node->lock); + INIT_LIST_HEAD(&node->work.entry); + INIT_LIST_HEAD(&node->async_todo); + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d:%d node %d u%016llx c%016llx created\n", + proc->pid, current->pid, node->debug_id, + (u64)node->ptr, (u64)node->cookie); + + return node; +} + +static struct binder_node *binder_new_node(struct binder_proc *proc, + struct flat_binder_object *fp) +{ + struct binder_node *node; + struct binder_node *new_node = kzalloc(sizeof(*node), GFP_KERNEL); + + if (!new_node) + return NULL; + binder_inner_proc_lock(proc); + node = binder_init_node_ilocked(proc, new_node, fp); + binder_inner_proc_unlock(proc); + if (node != new_node) + /* + * The node was already added by another thread + */ + kfree(new_node); + + return node; +} + +static void binder_free_node(struct binder_node *node) +{ + kfree(node); + binder_stats_deleted(BINDER_STAT_NODE); +} + +static int binder_inc_node_nilocked(struct binder_node *node, int strong, + int internal, + struct list_head *target_list) +{ + struct binder_proc *proc = node->proc; + + assert_spin_locked(&node->lock); + if (proc) + assert_spin_locked(&proc->inner_lock); + if (strong) { + if (internal) { + if (target_list == NULL && + node->internal_strong_refs == 0 && + !(node->proc && + node == node->proc->context->binder_context_mgr_node && + node->has_strong_ref)) { + pr_err("invalid inc strong node for %d\n", + node->debug_id); + return -EINVAL; + } + node->internal_strong_refs++; + } else + node->local_strong_refs++; + if (!node->has_strong_ref && target_list) { + struct binder_thread *thread = container_of(target_list, + struct binder_thread, todo); + binder_dequeue_work_ilocked(&node->work); + BUG_ON(&thread->todo != target_list); + binder_enqueue_deferred_thread_work_ilocked(thread, + &node->work); + } + } else { + if (!internal) + node->local_weak_refs++; + if (!node->has_weak_ref && list_empty(&node->work.entry)) { + if (target_list == NULL) { + pr_err("invalid inc weak node for %d\n", + node->debug_id); + return -EINVAL; + } + /* + * See comment above + */ + binder_enqueue_work_ilocked(&node->work, target_list); + } + } + return 0; +} + +static int binder_inc_node(struct binder_node *node, int strong, int internal, + struct list_head *target_list) +{ + int ret; + + binder_node_inner_lock(node); + ret = binder_inc_node_nilocked(node, strong, internal, target_list); + binder_node_inner_unlock(node); + + return ret; +} + +static bool binder_dec_node_nilocked(struct binder_node *node, + int strong, int internal) +{ + struct binder_proc *proc = node->proc; + + assert_spin_locked(&node->lock); + if (proc) + assert_spin_locked(&proc->inner_lock); + if (strong) { + if (internal) + node->internal_strong_refs--; + else + node->local_strong_refs--; + if (node->local_strong_refs || node->internal_strong_refs) + return false; + } else { + if (!internal) + node->local_weak_refs--; + if (node->local_weak_refs || node->tmp_refs || + !hlist_empty(&node->refs)) + return false; + } + + if (proc && (node->has_strong_ref || node->has_weak_ref)) { + if (list_empty(&node->work.entry)) { + binder_enqueue_work_ilocked(&node->work, &proc->todo); + binder_wakeup_proc_ilocked(proc); + } + } else { + if (hlist_empty(&node->refs) && !node->local_strong_refs && + !node->local_weak_refs && !node->tmp_refs) { + if (proc) { + binder_dequeue_work_ilocked(&node->work); + rb_erase(&node->rb_node, &proc->nodes); + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "refless node %d deleted\n", + node->debug_id); + } else { + BUG_ON(!list_empty(&node->work.entry)); + spin_lock(&binder_dead_nodes_lock); + /* + * tmp_refs could have changed so + * check it again + */ + if (node->tmp_refs) { + spin_unlock(&binder_dead_nodes_lock); + return false; + } + hlist_del(&node->dead_node); + spin_unlock(&binder_dead_nodes_lock); + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "dead node %d deleted\n", + node->debug_id); + } + return true; + } + } + return false; +} + +static void binder_dec_node(struct binder_node *node, int strong, int internal) +{ + bool free_node; + + binder_node_inner_lock(node); + free_node = binder_dec_node_nilocked(node, strong, internal); + binder_node_inner_unlock(node); + if (free_node) + binder_free_node(node); +} + +static void binder_inc_node_tmpref_ilocked(struct binder_node *node) +{ + /* + * No call to binder_inc_node() is needed since we + * don't need to inform userspace of any changes to + * tmp_refs + */ + node->tmp_refs++; +} + +/** + * binder_inc_node_tmpref() - take a temporary reference on node + * @node: node to reference + * + * Take reference on node to prevent the node from being freed + * while referenced only by a local variable. The inner lock is + * needed to serialize with the node work on the queue (which + * isn't needed after the node is dead). If the node is dead + * (node->proc is NULL), use binder_dead_nodes_lock to protect + * node->tmp_refs against dead-node-only cases where the node + * lock cannot be acquired (eg traversing the dead node list to + * print nodes) + */ +static void binder_inc_node_tmpref(struct binder_node *node) +{ + binder_node_lock(node); + if (node->proc) + binder_inner_proc_lock(node->proc); + else + spin_lock(&binder_dead_nodes_lock); + binder_inc_node_tmpref_ilocked(node); + if (node->proc) + binder_inner_proc_unlock(node->proc); + else + spin_unlock(&binder_dead_nodes_lock); + binder_node_unlock(node); +} + +/** + * binder_dec_node_tmpref() - remove a temporary reference on node + * @node: node to reference + * + * Release temporary reference on node taken via binder_inc_node_tmpref() + */ +static void binder_dec_node_tmpref(struct binder_node *node) +{ + bool free_node; + + binder_node_inner_lock(node); + if (!node->proc) + spin_lock(&binder_dead_nodes_lock); + else + __acquire(&binder_dead_nodes_lock); + node->tmp_refs--; + BUG_ON(node->tmp_refs < 0); + if (!node->proc) + spin_unlock(&binder_dead_nodes_lock); + else + __release(&binder_dead_nodes_lock); + /* + * Call binder_dec_node() to check if all refcounts are 0 + * and cleanup is needed. Calling with strong=0 and internal=1 + * causes no actual reference to be released in binder_dec_node(). + * If that changes, a change is needed here too. + */ + free_node = binder_dec_node_nilocked(node, 0, 1); + binder_node_inner_unlock(node); + if (free_node) + binder_free_node(node); +} + +static void binder_put_node(struct binder_node *node) +{ + binder_dec_node_tmpref(node); +} + +static struct binder_ref *binder_get_ref_olocked(struct binder_proc *proc, + u32 desc, bool need_strong_ref) +{ + struct rb_node *n = proc->refs_by_desc.rb_node; + struct binder_ref *ref; + + while (n) { + ref = rb_entry(n, struct binder_ref, rb_node_desc); + + if (desc < ref->data.desc) { + n = n->rb_left; + } else if (desc > ref->data.desc) { + n = n->rb_right; + } else if (need_strong_ref && !ref->data.strong) { + binder_user_error("tried to use weak ref as strong ref\n"); + return NULL; + } else { + return ref; + } + } + return NULL; +} + +/** + * binder_get_ref_for_node_olocked() - get the ref associated with given node + * @proc: binder_proc that owns the ref + * @node: binder_node of target + * @new_ref: newly allocated binder_ref to be initialized or %NULL + * + * Look up the ref for the given node and return it if it exists + * + * If it doesn't exist and the caller provides a newly allocated + * ref, initialize the fields of the newly allocated ref and insert + * into the given proc rb_trees and node refs list. + * + * Return: the ref for node. It is possible that another thread + * allocated/initialized the ref first in which case the + * returned ref would be different than the passed-in + * new_ref. new_ref must be kfree'd by the caller in + * this case. + */ +static struct binder_ref *binder_get_ref_for_node_olocked( + struct binder_proc *proc, + struct binder_node *node, + struct binder_ref *new_ref) +{ + struct binder_context *context = proc->context; + struct rb_node **p = &proc->refs_by_node.rb_node; + struct rb_node *parent = NULL; + struct binder_ref *ref; + struct rb_node *n; + + while (*p) { + parent = *p; + ref = rb_entry(parent, struct binder_ref, rb_node_node); + + if (node < ref->node) + p = &(*p)->rb_left; + else if (node > ref->node) + p = &(*p)->rb_right; + else + return ref; + } + if (!new_ref) + return NULL; + + binder_stats_created(BINDER_STAT_REF); + new_ref->data.debug_id = atomic_inc_return(&binder_last_id); + new_ref->proc = proc; + new_ref->node = node; + rb_link_node(&new_ref->rb_node_node, parent, p); + rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node); + + new_ref->data.desc = (node == context->binder_context_mgr_node) ? 0 : 1; + for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) { + ref = rb_entry(n, struct binder_ref, rb_node_desc); + if (ref->data.desc > new_ref->data.desc) + break; + new_ref->data.desc = ref->data.desc + 1; + } + + p = &proc->refs_by_desc.rb_node; + while (*p) { + parent = *p; + ref = rb_entry(parent, struct binder_ref, rb_node_desc); + + if (new_ref->data.desc < ref->data.desc) + p = &(*p)->rb_left; + else if (new_ref->data.desc > ref->data.desc) + p = &(*p)->rb_right; + else + BUG(); + } + rb_link_node(&new_ref->rb_node_desc, parent, p); + rb_insert_color(&new_ref->rb_node_desc, &proc->refs_by_desc); + + binder_node_lock(node); + hlist_add_head(&new_ref->node_entry, &node->refs); + + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d new ref %d desc %d for node %d\n", + proc->pid, new_ref->data.debug_id, new_ref->data.desc, + node->debug_id); + binder_node_unlock(node); + return new_ref; +} + +static void binder_cleanup_ref_olocked(struct binder_ref *ref) +{ + bool delete_node = false; + + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d delete ref %d desc %d for node %d\n", + ref->proc->pid, ref->data.debug_id, ref->data.desc, + ref->node->debug_id); + + rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc); + rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node); + + binder_node_inner_lock(ref->node); + if (ref->data.strong) + binder_dec_node_nilocked(ref->node, 1, 1); + + hlist_del(&ref->node_entry); + delete_node = binder_dec_node_nilocked(ref->node, 0, 1); + binder_node_inner_unlock(ref->node); + /* + * Clear ref->node unless we want the caller to free the node + */ + if (!delete_node) { + /* + * The caller uses ref->node to determine + * whether the node needs to be freed. Clear + * it since the node is still alive. + */ + ref->node = NULL; + } + + if (ref->death) { + binder_debug(BINDER_DEBUG_DEAD_BINDER, + "%d delete ref %d desc %d has death notification\n", + ref->proc->pid, ref->data.debug_id, + ref->data.desc); + binder_dequeue_work(ref->proc, &ref->death->work); + binder_stats_deleted(BINDER_STAT_DEATH); + } + binder_stats_deleted(BINDER_STAT_REF); +} + +/** + * binder_inc_ref_olocked() - increment the ref for given handle + * @ref: ref to be incremented + * @strong: if true, strong increment, else weak + * @target_list: list to queue node work on + * + * Increment the ref. @ref->proc->outer_lock must be held on entry + * + * Return: 0, if successful, else errno + */ +static int binder_inc_ref_olocked(struct binder_ref *ref, int strong, + struct list_head *target_list) +{ + int ret; + + if (strong) { + if (ref->data.strong == 0) { + ret = binder_inc_node(ref->node, 1, 1, target_list); + if (ret) + return ret; + } + ref->data.strong++; + } else { + if (ref->data.weak == 0) { + ret = binder_inc_node(ref->node, 0, 1, target_list); + if (ret) + return ret; + } + ref->data.weak++; + } + return 0; +} + +/** + * binder_dec_ref() - dec the ref for given handle + * @ref: ref to be decremented + * @strong: if true, strong decrement, else weak + * + * Decrement the ref. + * + * Return: true if ref is cleaned up and ready to be freed + */ +static bool binder_dec_ref_olocked(struct binder_ref *ref, int strong) +{ + if (strong) { + if (ref->data.strong == 0) { + binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n", + ref->proc->pid, ref->data.debug_id, + ref->data.desc, ref->data.strong, + ref->data.weak); + return false; + } + ref->data.strong--; + if (ref->data.strong == 0) + binder_dec_node(ref->node, strong, 1); + } else { + if (ref->data.weak == 0) { + binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n", + ref->proc->pid, ref->data.debug_id, + ref->data.desc, ref->data.strong, + ref->data.weak); + return false; + } + ref->data.weak--; + } + if (ref->data.strong == 0 && ref->data.weak == 0) { + binder_cleanup_ref_olocked(ref); + return true; + } + return false; +} + +/** + * binder_get_node_from_ref() - get the node from the given proc/desc + * @proc: proc containing the ref + * @desc: the handle associated with the ref + * @need_strong_ref: if true, only return node if ref is strong + * @rdata: the id/refcount data for the ref + * + * Given a proc and ref handle, return the associated binder_node + * + * Return: a binder_node or NULL if not found or not strong when strong required + */ +static struct binder_node *binder_get_node_from_ref( + struct binder_proc *proc, + u32 desc, bool need_strong_ref, + struct binder_ref_data *rdata) +{ + struct binder_node *node; + struct binder_ref *ref; + + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, desc, need_strong_ref); + if (!ref) + goto err_no_ref; + node = ref->node; + /* + * Take an implicit reference on the node to ensure + * it stays alive until the call to binder_put_node() + */ + binder_inc_node_tmpref(node); + if (rdata) + *rdata = ref->data; + binder_proc_unlock(proc); + + return node; + +err_no_ref: + binder_proc_unlock(proc); + return NULL; +} + +/** + * binder_free_ref() - free the binder_ref + * @ref: ref to free + * + * Free the binder_ref. Free the binder_node indicated by ref->node + * (if non-NULL) and the binder_ref_death indicated by ref->death. + */ +static void binder_free_ref(struct binder_ref *ref) +{ + if (ref->node) + binder_free_node(ref->node); + kfree(ref->death); + kfree(ref); +} + +/** + * binder_update_ref_for_handle() - inc/dec the ref for given handle + * @proc: proc containing the ref + * @desc: the handle associated with the ref + * @increment: true=inc reference, false=dec reference + * @strong: true=strong reference, false=weak reference + * @rdata: the id/refcount data for the ref + * + * Given a proc and ref handle, increment or decrement the ref + * according to "increment" arg. + * + * Return: 0 if successful, else errno + */ +static int binder_update_ref_for_handle(struct binder_proc *proc, + uint32_t desc, bool increment, bool strong, + struct binder_ref_data *rdata) +{ + int ret = 0; + struct binder_ref *ref; + bool delete_ref = false; + + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, desc, strong); + if (!ref) { + ret = -EINVAL; + goto err_no_ref; + } + if (increment) + ret = binder_inc_ref_olocked(ref, strong, NULL); + else + delete_ref = binder_dec_ref_olocked(ref, strong); + + if (rdata) + *rdata = ref->data; + binder_proc_unlock(proc); + + if (delete_ref) + binder_free_ref(ref); + return ret; + +err_no_ref: + binder_proc_unlock(proc); + return ret; +} + +/** + * binder_dec_ref_for_handle() - dec the ref for given handle + * @proc: proc containing the ref + * @desc: the handle associated with the ref + * @strong: true=strong reference, false=weak reference + * @rdata: the id/refcount data for the ref + * + * Just calls binder_update_ref_for_handle() to decrement the ref. + * + * Return: 0 if successful, else errno + */ +static int binder_dec_ref_for_handle(struct binder_proc *proc, + uint32_t desc, bool strong, struct binder_ref_data *rdata) +{ + return binder_update_ref_for_handle(proc, desc, false, strong, rdata); +} + + +/** + * binder_inc_ref_for_node() - increment the ref for given proc/node + * @proc: proc containing the ref + * @node: target node + * @strong: true=strong reference, false=weak reference + * @target_list: worklist to use if node is incremented + * @rdata: the id/refcount data for the ref + * + * Given a proc and node, increment the ref. Create the ref if it + * doesn't already exist + * + * Return: 0 if successful, else errno + */ +static int binder_inc_ref_for_node(struct binder_proc *proc, + struct binder_node *node, + bool strong, + struct list_head *target_list, + struct binder_ref_data *rdata) +{ + struct binder_ref *ref; + struct binder_ref *new_ref = NULL; + int ret = 0; + + binder_proc_lock(proc); + ref = binder_get_ref_for_node_olocked(proc, node, NULL); + if (!ref) { + binder_proc_unlock(proc); + new_ref = kzalloc(sizeof(*ref), GFP_KERNEL); + if (!new_ref) + return -ENOMEM; + binder_proc_lock(proc); + ref = binder_get_ref_for_node_olocked(proc, node, new_ref); + } + ret = binder_inc_ref_olocked(ref, strong, target_list); + *rdata = ref->data; + if (ret && ref == new_ref) { + /* + * Cleanup the failed reference here as the target + * could now be dead and have already released its + * references by now. Calling on the new reference + * with strong=0 and a tmp_refs will not decrement + * the node. The new_ref gets kfree'd below. + */ + binder_cleanup_ref_olocked(new_ref); + ref = NULL; + } + + binder_proc_unlock(proc); + if (new_ref && ref != new_ref) + /* + * Another thread created the ref first so + * free the one we allocated + */ + kfree(new_ref); + return ret; +} + +static void binder_pop_transaction_ilocked(struct binder_thread *target_thread, + struct binder_transaction *t) +{ + BUG_ON(!target_thread); + assert_spin_locked(&target_thread->proc->inner_lock); + BUG_ON(target_thread->transaction_stack != t); + BUG_ON(target_thread->transaction_stack->from != target_thread); + target_thread->transaction_stack = + target_thread->transaction_stack->from_parent; + t->from = NULL; +} + +/** + * binder_thread_dec_tmpref() - decrement thread->tmp_ref + * @thread: thread to decrement + * + * A thread needs to be kept alive while being used to create or + * handle a transaction. binder_get_txn_from() is used to safely + * extract t->from from a binder_transaction and keep the thread + * indicated by t->from from being freed. When done with that + * binder_thread, this function is called to decrement the + * tmp_ref and free if appropriate (thread has been released + * and no transaction being processed by the driver) + */ +static void binder_thread_dec_tmpref(struct binder_thread *thread) +{ + /* + * atomic is used to protect the counter value while + * it cannot reach zero or thread->is_dead is false + */ + binder_inner_proc_lock(thread->proc); + atomic_dec(&thread->tmp_ref); + if (thread->is_dead && !atomic_read(&thread->tmp_ref)) { + binder_inner_proc_unlock(thread->proc); + binder_free_thread(thread); + return; + } + binder_inner_proc_unlock(thread->proc); +} + +/** + * binder_proc_dec_tmpref() - decrement proc->tmp_ref + * @proc: proc to decrement + * + * A binder_proc needs to be kept alive while being used to create or + * handle a transaction. proc->tmp_ref is incremented when + * creating a new transaction or the binder_proc is currently in-use + * by threads that are being released. When done with the binder_proc, + * this function is called to decrement the counter and free the + * proc if appropriate (proc has been released, all threads have + * been released and not currenly in-use to process a transaction). + */ +static void binder_proc_dec_tmpref(struct binder_proc *proc) +{ + binder_inner_proc_lock(proc); + proc->tmp_ref--; + if (proc->is_dead && RB_EMPTY_ROOT(&proc->threads) && + !proc->tmp_ref) { + binder_inner_proc_unlock(proc); + binder_free_proc(proc); + return; + } + binder_inner_proc_unlock(proc); +} + +/** + * binder_get_txn_from() - safely extract the "from" thread in transaction + * @t: binder transaction for t->from + * + * Atomically return the "from" thread and increment the tmp_ref + * count for the thread to ensure it stays alive until + * binder_thread_dec_tmpref() is called. + * + * Return: the value of t->from + */ +static struct binder_thread *binder_get_txn_from( + struct binder_transaction *t) +{ + struct binder_thread *from; + + spin_lock(&t->lock); + from = t->from; + if (from) + atomic_inc(&from->tmp_ref); + spin_unlock(&t->lock); + return from; +} + +/** + * binder_get_txn_from_and_acq_inner() - get t->from and acquire inner lock + * @t: binder transaction for t->from + * + * Same as binder_get_txn_from() except it also acquires the proc->inner_lock + * to guarantee that the thread cannot be released while operating on it. + * The caller must call binder_inner_proc_unlock() to release the inner lock + * as well as call binder_dec_thread_txn() to release the reference. + * + * Return: the value of t->from + */ +static struct binder_thread *binder_get_txn_from_and_acq_inner( + struct binder_transaction *t) + __acquires(&t->from->proc->inner_lock) +{ + struct binder_thread *from; + + from = binder_get_txn_from(t); + if (!from) { + __acquire(&from->proc->inner_lock); + return NULL; + } + binder_inner_proc_lock(from->proc); + if (t->from) { + BUG_ON(from != t->from); + return from; + } + binder_inner_proc_unlock(from->proc); + __acquire(&from->proc->inner_lock); + binder_thread_dec_tmpref(from); + return NULL; +} + +/** + * binder_free_txn_fixups() - free unprocessed fd fixups + * @t: binder transaction for t->from + * + * If the transaction is being torn down prior to being + * processed by the target process, free all of the + * fd fixups and fput the file structs. It is safe to + * call this function after the fixups have been + * processed -- in that case, the list will be empty. + */ +static void binder_free_txn_fixups(struct binder_transaction *t) +{ + struct binder_txn_fd_fixup *fixup, *tmp; + + list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) { + fput(fixup->file); + if (fixup->target_fd >= 0) + put_unused_fd(fixup->target_fd); + list_del(&fixup->fixup_entry); + kfree(fixup); + } +} + +static void binder_txn_latency_free(struct binder_transaction *t) +{ + int from_proc, from_thread, to_proc, to_thread; + + spin_lock(&t->lock); + from_proc = t->from ? t->from->proc->pid : 0; + from_thread = t->from ? t->from->pid : 0; + to_proc = t->to_proc ? t->to_proc->pid : 0; + to_thread = t->to_thread ? t->to_thread->pid : 0; + spin_unlock(&t->lock); + + trace_binder_txn_latency_free(t, from_proc, from_thread, to_proc, to_thread); +} + +static void binder_free_transaction(struct binder_transaction *t) +{ + struct binder_proc *target_proc = t->to_proc; + + if (target_proc) { + binder_inner_proc_lock(target_proc); + target_proc->outstanding_txns--; + if (target_proc->outstanding_txns < 0) + pr_warn("%s: Unexpected outstanding_txns %d\n", + __func__, target_proc->outstanding_txns); + if (!target_proc->outstanding_txns && target_proc->is_frozen) + wake_up_interruptible_all(&target_proc->freeze_wait); + if (t->buffer) + t->buffer->transaction = NULL; + binder_inner_proc_unlock(target_proc); + } + if (trace_binder_txn_latency_free_enabled()) + binder_txn_latency_free(t); + /* + * If the transaction has no target_proc, then + * t->buffer->transaction has already been cleared. + */ + binder_free_txn_fixups(t); + kfree(t); + binder_stats_deleted(BINDER_STAT_TRANSACTION); +} + +static void binder_send_failed_reply(struct binder_transaction *t, + uint32_t error_code) +{ + struct binder_thread *target_thread; + struct binder_transaction *next; + + BUG_ON(t->flags & TF_ONE_WAY); + while (1) { + target_thread = binder_get_txn_from_and_acq_inner(t); + if (target_thread) { + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, + "send failed reply for transaction %d to %d:%d\n", + t->debug_id, + target_thread->proc->pid, + target_thread->pid); + + binder_pop_transaction_ilocked(target_thread, t); + if (target_thread->reply_error.cmd == BR_OK) { + target_thread->reply_error.cmd = error_code; + binder_enqueue_thread_work_ilocked( + target_thread, + &target_thread->reply_error.work); + wake_up_interruptible(&target_thread->wait); + } else { + /* + * Cannot get here for normal operation, but + * we can if multiple synchronous transactions + * are sent without blocking for responses. + * Just ignore the 2nd error in this case. + */ + pr_warn("Unexpected reply error: %u\n", + target_thread->reply_error.cmd); + } + binder_inner_proc_unlock(target_thread->proc); + binder_thread_dec_tmpref(target_thread); + binder_free_transaction(t); + return; + } + __release(&target_thread->proc->inner_lock); + next = t->from_parent; + + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, + "send failed reply for transaction %d, target dead\n", + t->debug_id); + + binder_free_transaction(t); + if (next == NULL) { + binder_debug(BINDER_DEBUG_DEAD_BINDER, + "reply failed, no target thread at root\n"); + return; + } + t = next; + binder_debug(BINDER_DEBUG_DEAD_BINDER, + "reply failed, no target thread -- retry %d\n", + t->debug_id); + } +} + +/** + * binder_cleanup_transaction() - cleans up undelivered transaction + * @t: transaction that needs to be cleaned up + * @reason: reason the transaction wasn't delivered + * @error_code: error to return to caller (if synchronous call) + */ +static void binder_cleanup_transaction(struct binder_transaction *t, + const char *reason, + uint32_t error_code) +{ + if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) { + binder_send_failed_reply(t, error_code); + } else { + binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, + "undelivered transaction %d, %s\n", + t->debug_id, reason); + binder_free_transaction(t); + } +} + +/** + * binder_get_object() - gets object and checks for valid metadata + * @proc: binder_proc owning the buffer + * @u: sender's user pointer to base of buffer + * @buffer: binder_buffer that we're parsing. + * @offset: offset in the @buffer at which to validate an object. + * @object: struct binder_object to read into + * + * Copy the binder object at the given offset into @object. If @u is + * provided then the copy is from the sender's buffer. If not, then + * it is copied from the target's @buffer. + * + * Return: If there's a valid metadata object at @offset, the + * size of that object. Otherwise, it returns zero. The object + * is read into the struct binder_object pointed to by @object. + */ +static size_t binder_get_object(struct binder_proc *proc, + const void __user *u, + struct binder_buffer *buffer, + unsigned long offset, + struct binder_object *object) +{ + size_t read_size; + struct binder_object_header *hdr; + size_t object_size = 0; + + read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset); + if (offset > buffer->data_size || read_size < sizeof(*hdr)) + return 0; + if (u) { + if (copy_from_user(object, u + offset, read_size)) + return 0; + } else { + if (binder_alloc_copy_from_buffer(&proc->alloc, object, buffer, + offset, read_size)) + return 0; + } + + /* Ok, now see if we read a complete object. */ + hdr = &object->hdr; + switch (hdr->type) { + case BINDER_TYPE_BINDER: + case BINDER_TYPE_WEAK_BINDER: + case BINDER_TYPE_HANDLE: + case BINDER_TYPE_WEAK_HANDLE: + object_size = sizeof(struct flat_binder_object); + break; + case BINDER_TYPE_FD: + object_size = sizeof(struct binder_fd_object); + break; + case BINDER_TYPE_PTR: + object_size = sizeof(struct binder_buffer_object); + break; + case BINDER_TYPE_FDA: + object_size = sizeof(struct binder_fd_array_object); + break; + default: + return 0; + } + if (offset <= buffer->data_size - object_size && + buffer->data_size >= object_size) + return object_size; + else + return 0; +} + +/** + * binder_validate_ptr() - validates binder_buffer_object in a binder_buffer. + * @proc: binder_proc owning the buffer + * @b: binder_buffer containing the object + * @object: struct binder_object to read into + * @index: index in offset array at which the binder_buffer_object is + * located + * @start_offset: points to the start of the offset array + * @object_offsetp: offset of @object read from @b + * @num_valid: the number of valid offsets in the offset array + * + * Return: If @index is within the valid range of the offset array + * described by @start and @num_valid, and if there's a valid + * binder_buffer_object at the offset found in index @index + * of the offset array, that object is returned. Otherwise, + * %NULL is returned. + * Note that the offset found in index @index itself is not + * verified; this function assumes that @num_valid elements + * from @start were previously verified to have valid offsets. + * If @object_offsetp is non-NULL, then the offset within + * @b is written to it. + */ +static struct binder_buffer_object *binder_validate_ptr( + struct binder_proc *proc, + struct binder_buffer *b, + struct binder_object *object, + binder_size_t index, + binder_size_t start_offset, + binder_size_t *object_offsetp, + binder_size_t num_valid) +{ + size_t object_size; + binder_size_t object_offset; + unsigned long buffer_offset; + + if (index >= num_valid) + return NULL; + + buffer_offset = start_offset + sizeof(binder_size_t) * index; + if (binder_alloc_copy_from_buffer(&proc->alloc, &object_offset, + b, buffer_offset, + sizeof(object_offset))) + return NULL; + object_size = binder_get_object(proc, NULL, b, object_offset, object); + if (!object_size || object->hdr.type != BINDER_TYPE_PTR) + return NULL; + if (object_offsetp) + *object_offsetp = object_offset; + + return &object->bbo; +} + +/** + * binder_validate_fixup() - validates pointer/fd fixups happen in order. + * @proc: binder_proc owning the buffer + * @b: transaction buffer + * @objects_start_offset: offset to start of objects buffer + * @buffer_obj_offset: offset to binder_buffer_object in which to fix up + * @fixup_offset: start offset in @buffer to fix up + * @last_obj_offset: offset to last binder_buffer_object that we fixed + * @last_min_offset: minimum fixup offset in object at @last_obj_offset + * + * Return: %true if a fixup in buffer @buffer at offset @offset is + * allowed. + * + * For safety reasons, we only allow fixups inside a buffer to happen + * at increasing offsets; additionally, we only allow fixup on the last + * buffer object that was verified, or one of its parents. + * + * Example of what is allowed: + * + * A + * B (parent = A, offset = 0) + * C (parent = A, offset = 16) + * D (parent = C, offset = 0) + * E (parent = A, offset = 32) // min_offset is 16 (C.parent_offset) + * + * Examples of what is not allowed: + * + * Decreasing offsets within the same parent: + * A + * C (parent = A, offset = 16) + * B (parent = A, offset = 0) // decreasing offset within A + * + * Referring to a parent that wasn't the last object or any of its parents: + * A + * B (parent = A, offset = 0) + * C (parent = A, offset = 0) + * C (parent = A, offset = 16) + * D (parent = B, offset = 0) // B is not A or any of A's parents + */ +static bool binder_validate_fixup(struct binder_proc *proc, + struct binder_buffer *b, + binder_size_t objects_start_offset, + binder_size_t buffer_obj_offset, + binder_size_t fixup_offset, + binder_size_t last_obj_offset, + binder_size_t last_min_offset) +{ + if (!last_obj_offset) { + /* Nothing to fix up in */ + return false; + } + + while (last_obj_offset != buffer_obj_offset) { + unsigned long buffer_offset; + struct binder_object last_object; + struct binder_buffer_object *last_bbo; + size_t object_size = binder_get_object(proc, NULL, b, + last_obj_offset, + &last_object); + if (object_size != sizeof(*last_bbo)) + return false; + + last_bbo = &last_object.bbo; + /* + * Safe to retrieve the parent of last_obj, since it + * was already previously verified by the driver. + */ + if ((last_bbo->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0) + return false; + last_min_offset = last_bbo->parent_offset + sizeof(uintptr_t); + buffer_offset = objects_start_offset + + sizeof(binder_size_t) * last_bbo->parent; + if (binder_alloc_copy_from_buffer(&proc->alloc, + &last_obj_offset, + b, buffer_offset, + sizeof(last_obj_offset))) + return false; + } + return (fixup_offset >= last_min_offset); +} + +/** + * struct binder_task_work_cb - for deferred close + * + * @twork: callback_head for task work + * @fd: fd to close + * + * Structure to pass task work to be handled after + * returning from binder_ioctl() via task_work_add(). + */ +struct binder_task_work_cb { + struct callback_head twork; + struct file *file; +}; + +/** + * binder_do_fd_close() - close list of file descriptors + * @twork: callback head for task work + * + * It is not safe to call ksys_close() during the binder_ioctl() + * function if there is a chance that binder's own file descriptor + * might be closed. This is to meet the requirements for using + * fdget() (see comments for __fget_light()). Therefore use + * task_work_add() to schedule the close operation once we have + * returned from binder_ioctl(). This function is a callback + * for that mechanism and does the actual ksys_close() on the + * given file descriptor. + */ +static void binder_do_fd_close(struct callback_head *twork) +{ + struct binder_task_work_cb *twcb = container_of(twork, + struct binder_task_work_cb, twork); + + fput(twcb->file); + kfree(twcb); +} + +/** + * binder_deferred_fd_close() - schedule a close for the given file-descriptor + * @fd: file-descriptor to close + * + * See comments in binder_do_fd_close(). This function is used to schedule + * a file-descriptor to be closed after returning from binder_ioctl(). + */ +static void binder_deferred_fd_close(int fd) +{ + struct binder_task_work_cb *twcb; + + twcb = kzalloc(sizeof(*twcb), GFP_KERNEL); + if (!twcb) + return; + init_task_work(&twcb->twork, binder_do_fd_close); + twcb->file = close_fd_get_file(fd); + if (twcb->file) { + // pin it until binder_do_fd_close(); see comments there + get_file(twcb->file); + filp_close(twcb->file, current->files); + task_work_add(current, &twcb->twork, TWA_RESUME); + } else { + kfree(twcb); + } +} + +static void binder_transaction_buffer_release(struct binder_proc *proc, + struct binder_thread *thread, + struct binder_buffer *buffer, + binder_size_t off_end_offset, + bool is_failure) +{ + int debug_id = buffer->debug_id; + binder_size_t off_start_offset, buffer_offset; + + binder_debug(BINDER_DEBUG_TRANSACTION, + "%d buffer release %d, size %zd-%zd, failed at %llx\n", + proc->pid, buffer->debug_id, + buffer->data_size, buffer->offsets_size, + (unsigned long long)off_end_offset); + + if (buffer->target_node) + binder_dec_node(buffer->target_node, 1, 0); + + off_start_offset = ALIGN(buffer->data_size, sizeof(void *)); + + for (buffer_offset = off_start_offset; buffer_offset < off_end_offset; + buffer_offset += sizeof(binder_size_t)) { + struct binder_object_header *hdr; + size_t object_size = 0; + struct binder_object object; + binder_size_t object_offset; + + if (!binder_alloc_copy_from_buffer(&proc->alloc, &object_offset, + buffer, buffer_offset, + sizeof(object_offset))) + object_size = binder_get_object(proc, NULL, buffer, + object_offset, &object); + if (object_size == 0) { + pr_err("transaction release %d bad object at offset %lld, size %zd\n", + debug_id, (u64)object_offset, buffer->data_size); + continue; + } + hdr = &object.hdr; + switch (hdr->type) { + case BINDER_TYPE_BINDER: + case BINDER_TYPE_WEAK_BINDER: { + struct flat_binder_object *fp; + struct binder_node *node; + + fp = to_flat_binder_object(hdr); + node = binder_get_node(proc, fp->binder); + if (node == NULL) { + pr_err("transaction release %d bad node %016llx\n", + debug_id, (u64)fp->binder); + break; + } + binder_debug(BINDER_DEBUG_TRANSACTION, + " node %d u%016llx\n", + node->debug_id, (u64)node->ptr); + binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER, + 0); + binder_put_node(node); + } break; + case BINDER_TYPE_HANDLE: + case BINDER_TYPE_WEAK_HANDLE: { + struct flat_binder_object *fp; + struct binder_ref_data rdata; + int ret; + + fp = to_flat_binder_object(hdr); + ret = binder_dec_ref_for_handle(proc, fp->handle, + hdr->type == BINDER_TYPE_HANDLE, &rdata); + + if (ret) { + pr_err("transaction release %d bad handle %d, ret = %d\n", + debug_id, fp->handle, ret); + break; + } + binder_debug(BINDER_DEBUG_TRANSACTION, + " ref %d desc %d\n", + rdata.debug_id, rdata.desc); + } break; + + case BINDER_TYPE_FD: { + /* + * No need to close the file here since user-space + * closes it for successfully delivered + * transactions. For transactions that weren't + * delivered, the new fd was never allocated so + * there is no need to close and the fput on the + * file is done when the transaction is torn + * down. + */ + } break; + case BINDER_TYPE_PTR: + /* + * Nothing to do here, this will get cleaned up when the + * transaction buffer gets freed + */ + break; + case BINDER_TYPE_FDA: { + struct binder_fd_array_object *fda; + struct binder_buffer_object *parent; + struct binder_object ptr_object; + binder_size_t fda_offset; + size_t fd_index; + binder_size_t fd_buf_size; + binder_size_t num_valid; + + if (is_failure) { + /* + * The fd fixups have not been applied so no + * fds need to be closed. + */ + continue; + } + + num_valid = (buffer_offset - off_start_offset) / + sizeof(binder_size_t); + fda = to_binder_fd_array_object(hdr); + parent = binder_validate_ptr(proc, buffer, &ptr_object, + fda->parent, + off_start_offset, + NULL, + num_valid); + if (!parent) { + pr_err("transaction release %d bad parent offset\n", + debug_id); + continue; + } + fd_buf_size = sizeof(u32) * fda->num_fds; + if (fda->num_fds >= SIZE_MAX / sizeof(u32)) { + pr_err("transaction release %d invalid number of fds (%lld)\n", + debug_id, (u64)fda->num_fds); + continue; + } + if (fd_buf_size > parent->length || + fda->parent_offset > parent->length - fd_buf_size) { + /* No space for all file descriptors here. */ + pr_err("transaction release %d not enough space for %lld fds in buffer\n", + debug_id, (u64)fda->num_fds); + continue; + } + /* + * the source data for binder_buffer_object is visible + * to user-space and the @buffer element is the user + * pointer to the buffer_object containing the fd_array. + * Convert the address to an offset relative to + * the base of the transaction buffer. + */ + fda_offset = + (parent->buffer - (uintptr_t)buffer->user_data) + + fda->parent_offset; + for (fd_index = 0; fd_index < fda->num_fds; + fd_index++) { + u32 fd; + int err; + binder_size_t offset = fda_offset + + fd_index * sizeof(fd); + + err = binder_alloc_copy_from_buffer( + &proc->alloc, &fd, buffer, + offset, sizeof(fd)); + WARN_ON(err); + if (!err) { + binder_deferred_fd_close(fd); + /* + * Need to make sure the thread goes + * back to userspace to complete the + * deferred close + */ + if (thread) + thread->looper_need_return = true; + } + } + } break; + default: + pr_err("transaction release %d bad object type %x\n", + debug_id, hdr->type); + break; + } + } +} + +/* Clean up all the objects in the buffer */ +static inline void binder_release_entire_buffer(struct binder_proc *proc, + struct binder_thread *thread, + struct binder_buffer *buffer, + bool is_failure) +{ + binder_size_t off_end_offset; + + off_end_offset = ALIGN(buffer->data_size, sizeof(void *)); + off_end_offset += buffer->offsets_size; + + binder_transaction_buffer_release(proc, thread, buffer, + off_end_offset, is_failure); +} + +static int binder_translate_binder(struct flat_binder_object *fp, + struct binder_transaction *t, + struct binder_thread *thread) +{ + struct binder_node *node; + struct binder_proc *proc = thread->proc; + struct binder_proc *target_proc = t->to_proc; + struct binder_ref_data rdata; + int ret = 0; + + node = binder_get_node(proc, fp->binder); + if (!node) { + node = binder_new_node(proc, fp); + if (!node) + return -ENOMEM; + } + if (fp->cookie != node->cookie) { + binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n", + proc->pid, thread->pid, (u64)fp->binder, + node->debug_id, (u64)fp->cookie, + (u64)node->cookie); + ret = -EINVAL; + goto done; + } + if (security_binder_transfer_binder(proc->cred, target_proc->cred)) { + ret = -EPERM; + goto done; + } + + ret = binder_inc_ref_for_node(target_proc, node, + fp->hdr.type == BINDER_TYPE_BINDER, + &thread->todo, &rdata); + if (ret) + goto done; + + if (fp->hdr.type == BINDER_TYPE_BINDER) + fp->hdr.type = BINDER_TYPE_HANDLE; + else + fp->hdr.type = BINDER_TYPE_WEAK_HANDLE; + fp->binder = 0; + fp->handle = rdata.desc; + fp->cookie = 0; + + trace_binder_transaction_node_to_ref(t, node, &rdata); + binder_debug(BINDER_DEBUG_TRANSACTION, + " node %d u%016llx -> ref %d desc %d\n", + node->debug_id, (u64)node->ptr, + rdata.debug_id, rdata.desc); +done: + binder_put_node(node); + return ret; +} + +static int binder_translate_handle(struct flat_binder_object *fp, + struct binder_transaction *t, + struct binder_thread *thread) +{ + struct binder_proc *proc = thread->proc; + struct binder_proc *target_proc = t->to_proc; + struct binder_node *node; + struct binder_ref_data src_rdata; + int ret = 0; + + node = binder_get_node_from_ref(proc, fp->handle, + fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata); + if (!node) { + binder_user_error("%d:%d got transaction with invalid handle, %d\n", + proc->pid, thread->pid, fp->handle); + return -EINVAL; + } + if (security_binder_transfer_binder(proc->cred, target_proc->cred)) { + ret = -EPERM; + goto done; + } + + binder_node_lock(node); + if (node->proc == target_proc) { + if (fp->hdr.type == BINDER_TYPE_HANDLE) + fp->hdr.type = BINDER_TYPE_BINDER; + else + fp->hdr.type = BINDER_TYPE_WEAK_BINDER; + fp->binder = node->ptr; + fp->cookie = node->cookie; + if (node->proc) + binder_inner_proc_lock(node->proc); + else + __acquire(&node->proc->inner_lock); + binder_inc_node_nilocked(node, + fp->hdr.type == BINDER_TYPE_BINDER, + 0, NULL); + if (node->proc) + binder_inner_proc_unlock(node->proc); + else + __release(&node->proc->inner_lock); + trace_binder_transaction_ref_to_node(t, node, &src_rdata); + binder_debug(BINDER_DEBUG_TRANSACTION, + " ref %d desc %d -> node %d u%016llx\n", + src_rdata.debug_id, src_rdata.desc, node->debug_id, + (u64)node->ptr); + binder_node_unlock(node); + } else { + struct binder_ref_data dest_rdata; + + binder_node_unlock(node); + ret = binder_inc_ref_for_node(target_proc, node, + fp->hdr.type == BINDER_TYPE_HANDLE, + NULL, &dest_rdata); + if (ret) + goto done; + + fp->binder = 0; + fp->handle = dest_rdata.desc; + fp->cookie = 0; + trace_binder_transaction_ref_to_ref(t, node, &src_rdata, + &dest_rdata); + binder_debug(BINDER_DEBUG_TRANSACTION, + " ref %d desc %d -> ref %d desc %d (node %d)\n", + src_rdata.debug_id, src_rdata.desc, + dest_rdata.debug_id, dest_rdata.desc, + node->debug_id); + } +done: + binder_put_node(node); + return ret; +} + +static int binder_translate_fd(u32 fd, binder_size_t fd_offset, + struct binder_transaction *t, + struct binder_thread *thread, + struct binder_transaction *in_reply_to) +{ + struct binder_proc *proc = thread->proc; + struct binder_proc *target_proc = t->to_proc; + struct binder_txn_fd_fixup *fixup; + struct file *file; + int ret = 0; + bool target_allows_fd; + + if (in_reply_to) + target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS); + else + target_allows_fd = t->buffer->target_node->accept_fds; + if (!target_allows_fd) { + binder_user_error("%d:%d got %s with fd, %d, but target does not allow fds\n", + proc->pid, thread->pid, + in_reply_to ? "reply" : "transaction", + fd); + ret = -EPERM; + goto err_fd_not_accepted; + } + + file = fget(fd); + if (!file) { + binder_user_error("%d:%d got transaction with invalid fd, %d\n", + proc->pid, thread->pid, fd); + ret = -EBADF; + goto err_fget; + } + ret = security_binder_transfer_file(proc->cred, target_proc->cred, file); + if (ret < 0) { + ret = -EPERM; + goto err_security; + } + + /* + * Add fixup record for this transaction. The allocation + * of the fd in the target needs to be done from a + * target thread. + */ + fixup = kzalloc(sizeof(*fixup), GFP_KERNEL); + if (!fixup) { + ret = -ENOMEM; + goto err_alloc; + } + fixup->file = file; + fixup->offset = fd_offset; + fixup->target_fd = -1; + trace_binder_transaction_fd_send(t, fd, fixup->offset); + list_add_tail(&fixup->fixup_entry, &t->fd_fixups); + + return ret; + +err_alloc: +err_security: + fput(file); +err_fget: +err_fd_not_accepted: + return ret; +} + +/** + * struct binder_ptr_fixup - data to be fixed-up in target buffer + * @offset offset in target buffer to fixup + * @skip_size bytes to skip in copy (fixup will be written later) + * @fixup_data data to write at fixup offset + * @node list node + * + * This is used for the pointer fixup list (pf) which is created and consumed + * during binder_transaction() and is only accessed locally. No + * locking is necessary. + * + * The list is ordered by @offset. + */ +struct binder_ptr_fixup { + binder_size_t offset; + size_t skip_size; + binder_uintptr_t fixup_data; + struct list_head node; +}; + +/** + * struct binder_sg_copy - scatter-gather data to be copied + * @offset offset in target buffer + * @sender_uaddr user address in source buffer + * @length bytes to copy + * @node list node + * + * This is used for the sg copy list (sgc) which is created and consumed + * during binder_transaction() and is only accessed locally. No + * locking is necessary. + * + * The list is ordered by @offset. + */ +struct binder_sg_copy { + binder_size_t offset; + const void __user *sender_uaddr; + size_t length; + struct list_head node; +}; + +/** + * binder_do_deferred_txn_copies() - copy and fixup scatter-gather data + * @alloc: binder_alloc associated with @buffer + * @buffer: binder buffer in target process + * @sgc_head: list_head of scatter-gather copy list + * @pf_head: list_head of pointer fixup list + * + * Processes all elements of @sgc_head, applying fixups from @pf_head + * and copying the scatter-gather data from the source process' user + * buffer to the target's buffer. It is expected that the list creation + * and processing all occurs during binder_transaction() so these lists + * are only accessed in local context. + * + * Return: 0=success, else -errno + */ +static int binder_do_deferred_txn_copies(struct binder_alloc *alloc, + struct binder_buffer *buffer, + struct list_head *sgc_head, + struct list_head *pf_head) +{ + int ret = 0; + struct binder_sg_copy *sgc, *tmpsgc; + struct binder_ptr_fixup *tmppf; + struct binder_ptr_fixup *pf = + list_first_entry_or_null(pf_head, struct binder_ptr_fixup, + node); + + list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) { + size_t bytes_copied = 0; + + while (bytes_copied < sgc->length) { + size_t copy_size; + size_t bytes_left = sgc->length - bytes_copied; + size_t offset = sgc->offset + bytes_copied; + + /* + * We copy up to the fixup (pointed to by pf) + */ + copy_size = pf ? min(bytes_left, (size_t)pf->offset - offset) + : bytes_left; + if (!ret && copy_size) + ret = binder_alloc_copy_user_to_buffer( + alloc, buffer, + offset, + sgc->sender_uaddr + bytes_copied, + copy_size); + bytes_copied += copy_size; + if (copy_size != bytes_left) { + BUG_ON(!pf); + /* we stopped at a fixup offset */ + if (pf->skip_size) { + /* + * we are just skipping. This is for + * BINDER_TYPE_FDA where the translated + * fds will be fixed up when we get + * to target context. + */ + bytes_copied += pf->skip_size; + } else { + /* apply the fixup indicated by pf */ + if (!ret) + ret = binder_alloc_copy_to_buffer( + alloc, buffer, + pf->offset, + &pf->fixup_data, + sizeof(pf->fixup_data)); + bytes_copied += sizeof(pf->fixup_data); + } + list_del(&pf->node); + kfree(pf); + pf = list_first_entry_or_null(pf_head, + struct binder_ptr_fixup, node); + } + } + list_del(&sgc->node); + kfree(sgc); + } + list_for_each_entry_safe(pf, tmppf, pf_head, node) { + BUG_ON(pf->skip_size == 0); + list_del(&pf->node); + kfree(pf); + } + BUG_ON(!list_empty(sgc_head)); + + return ret > 0 ? -EINVAL : ret; +} + +/** + * binder_cleanup_deferred_txn_lists() - free specified lists + * @sgc_head: list_head of scatter-gather copy list + * @pf_head: list_head of pointer fixup list + * + * Called to clean up @sgc_head and @pf_head if there is an + * error. + */ +static void binder_cleanup_deferred_txn_lists(struct list_head *sgc_head, + struct list_head *pf_head) +{ + struct binder_sg_copy *sgc, *tmpsgc; + struct binder_ptr_fixup *pf, *tmppf; + + list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) { + list_del(&sgc->node); + kfree(sgc); + } + list_for_each_entry_safe(pf, tmppf, pf_head, node) { + list_del(&pf->node); + kfree(pf); + } +} + +/** + * binder_defer_copy() - queue a scatter-gather buffer for copy + * @sgc_head: list_head of scatter-gather copy list + * @offset: binder buffer offset in target process + * @sender_uaddr: user address in source process + * @length: bytes to copy + * + * Specify a scatter-gather block to be copied. The actual copy must + * be deferred until all the needed fixups are identified and queued. + * Then the copy and fixups are done together so un-translated values + * from the source are never visible in the target buffer. + * + * We are guaranteed that repeated calls to this function will have + * monotonically increasing @offset values so the list will naturally + * be ordered. + * + * Return: 0=success, else -errno + */ +static int binder_defer_copy(struct list_head *sgc_head, binder_size_t offset, + const void __user *sender_uaddr, size_t length) +{ + struct binder_sg_copy *bc = kzalloc(sizeof(*bc), GFP_KERNEL); + + if (!bc) + return -ENOMEM; + + bc->offset = offset; + bc->sender_uaddr = sender_uaddr; + bc->length = length; + INIT_LIST_HEAD(&bc->node); + + /* + * We are guaranteed that the deferred copies are in-order + * so just add to the tail. + */ + list_add_tail(&bc->node, sgc_head); + + return 0; +} + +/** + * binder_add_fixup() - queue a fixup to be applied to sg copy + * @pf_head: list_head of binder ptr fixup list + * @offset: binder buffer offset in target process + * @fixup: bytes to be copied for fixup + * @skip_size: bytes to skip when copying (fixup will be applied later) + * + * Add the specified fixup to a list ordered by @offset. When copying + * the scatter-gather buffers, the fixup will be copied instead of + * data from the source buffer. For BINDER_TYPE_FDA fixups, the fixup + * will be applied later (in target process context), so we just skip + * the bytes specified by @skip_size. If @skip_size is 0, we copy the + * value in @fixup. + * + * This function is called *mostly* in @offset order, but there are + * exceptions. Since out-of-order inserts are relatively uncommon, + * we insert the new element by searching backward from the tail of + * the list. + * + * Return: 0=success, else -errno + */ +static int binder_add_fixup(struct list_head *pf_head, binder_size_t offset, + binder_uintptr_t fixup, size_t skip_size) +{ + struct binder_ptr_fixup *pf = kzalloc(sizeof(*pf), GFP_KERNEL); + struct binder_ptr_fixup *tmppf; + + if (!pf) + return -ENOMEM; + + pf->offset = offset; + pf->fixup_data = fixup; + pf->skip_size = skip_size; + INIT_LIST_HEAD(&pf->node); + + /* Fixups are *mostly* added in-order, but there are some + * exceptions. Look backwards through list for insertion point. + */ + list_for_each_entry_reverse(tmppf, pf_head, node) { + if (tmppf->offset < pf->offset) { + list_add(&pf->node, &tmppf->node); + return 0; + } + } + /* + * if we get here, then the new offset is the lowest so + * insert at the head + */ + list_add(&pf->node, pf_head); + return 0; +} + +static int binder_translate_fd_array(struct list_head *pf_head, + struct binder_fd_array_object *fda, + const void __user *sender_ubuffer, + struct binder_buffer_object *parent, + struct binder_buffer_object *sender_uparent, + struct binder_transaction *t, + struct binder_thread *thread, + struct binder_transaction *in_reply_to) +{ + binder_size_t fdi, fd_buf_size; + binder_size_t fda_offset; + const void __user *sender_ufda_base; + struct binder_proc *proc = thread->proc; + int ret; + + if (fda->num_fds == 0) + return 0; + + fd_buf_size = sizeof(u32) * fda->num_fds; + if (fda->num_fds >= SIZE_MAX / sizeof(u32)) { + binder_user_error("%d:%d got transaction with invalid number of fds (%lld)\n", + proc->pid, thread->pid, (u64)fda->num_fds); + return -EINVAL; + } + if (fd_buf_size > parent->length || + fda->parent_offset > parent->length - fd_buf_size) { + /* No space for all file descriptors here. */ + binder_user_error("%d:%d not enough space to store %lld fds in buffer\n", + proc->pid, thread->pid, (u64)fda->num_fds); + return -EINVAL; + } + /* + * the source data for binder_buffer_object is visible + * to user-space and the @buffer element is the user + * pointer to the buffer_object containing the fd_array. + * Convert the address to an offset relative to + * the base of the transaction buffer. + */ + fda_offset = (parent->buffer - (uintptr_t)t->buffer->user_data) + + fda->parent_offset; + sender_ufda_base = (void __user *)(uintptr_t)sender_uparent->buffer + + fda->parent_offset; + + if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32)) || + !IS_ALIGNED((unsigned long)sender_ufda_base, sizeof(u32))) { + binder_user_error("%d:%d parent offset not aligned correctly.\n", + proc->pid, thread->pid); + return -EINVAL; + } + ret = binder_add_fixup(pf_head, fda_offset, 0, fda->num_fds * sizeof(u32)); + if (ret) + return ret; + + for (fdi = 0; fdi < fda->num_fds; fdi++) { + u32 fd; + binder_size_t offset = fda_offset + fdi * sizeof(fd); + binder_size_t sender_uoffset = fdi * sizeof(fd); + + ret = copy_from_user(&fd, sender_ufda_base + sender_uoffset, sizeof(fd)); + if (!ret) + ret = binder_translate_fd(fd, offset, t, thread, + in_reply_to); + if (ret) + return ret > 0 ? -EINVAL : ret; + } + return 0; +} + +static int binder_fixup_parent(struct list_head *pf_head, + struct binder_transaction *t, + struct binder_thread *thread, + struct binder_buffer_object *bp, + binder_size_t off_start_offset, + binder_size_t num_valid, + binder_size_t last_fixup_obj_off, + binder_size_t last_fixup_min_off) +{ + struct binder_buffer_object *parent; + struct binder_buffer *b = t->buffer; + struct binder_proc *proc = thread->proc; + struct binder_proc *target_proc = t->to_proc; + struct binder_object object; + binder_size_t buffer_offset; + binder_size_t parent_offset; + + if (!(bp->flags & BINDER_BUFFER_FLAG_HAS_PARENT)) + return 0; + + parent = binder_validate_ptr(target_proc, b, &object, bp->parent, + off_start_offset, &parent_offset, + num_valid); + if (!parent) { + binder_user_error("%d:%d got transaction with invalid parent offset or type\n", + proc->pid, thread->pid); + return -EINVAL; + } + + if (!binder_validate_fixup(target_proc, b, off_start_offset, + parent_offset, bp->parent_offset, + last_fixup_obj_off, + last_fixup_min_off)) { + binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n", + proc->pid, thread->pid); + return -EINVAL; + } + + if (parent->length < sizeof(binder_uintptr_t) || + bp->parent_offset > parent->length - sizeof(binder_uintptr_t)) { + /* No space for a pointer here! */ + binder_user_error("%d:%d got transaction with invalid parent offset\n", + proc->pid, thread->pid); + return -EINVAL; + } + buffer_offset = bp->parent_offset + + (uintptr_t)parent->buffer - (uintptr_t)b->user_data; + return binder_add_fixup(pf_head, buffer_offset, bp->buffer, 0); +} + +/** + * binder_can_update_transaction() - Can a txn be superseded by an updated one? + * @t1: the pending async txn in the frozen process + * @t2: the new async txn to supersede the outdated pending one + * + * Return: true if t2 can supersede t1 + * false if t2 can not supersede t1 + */ +static bool binder_can_update_transaction(struct binder_transaction *t1, + struct binder_transaction *t2) +{ + if ((t1->flags & t2->flags & (TF_ONE_WAY | TF_UPDATE_TXN)) != + (TF_ONE_WAY | TF_UPDATE_TXN) || !t1->to_proc || !t2->to_proc) + return false; + if (t1->to_proc->tsk == t2->to_proc->tsk && t1->code == t2->code && + t1->flags == t2->flags && t1->buffer->pid == t2->buffer->pid && + t1->buffer->target_node->ptr == t2->buffer->target_node->ptr && + t1->buffer->target_node->cookie == t2->buffer->target_node->cookie) + return true; + return false; +} + +/** + * binder_find_outdated_transaction_ilocked() - Find the outdated transaction + * @t: new async transaction + * @target_list: list to find outdated transaction + * + * Return: the outdated transaction if found + * NULL if no outdated transacton can be found + * + * Requires the proc->inner_lock to be held. + */ +static struct binder_transaction * +binder_find_outdated_transaction_ilocked(struct binder_transaction *t, + struct list_head *target_list) +{ + struct binder_work *w; + + list_for_each_entry(w, target_list, entry) { + struct binder_transaction *t_queued; + + if (w->type != BINDER_WORK_TRANSACTION) + continue; + t_queued = container_of(w, struct binder_transaction, work); + if (binder_can_update_transaction(t_queued, t)) + return t_queued; + } + return NULL; +} + +/** + * binder_proc_transaction() - sends a transaction to a process and wakes it up + * @t: transaction to send + * @proc: process to send the transaction to + * @thread: thread in @proc to send the transaction to (may be NULL) + * + * This function queues a transaction to the specified process. It will try + * to find a thread in the target process to handle the transaction and + * wake it up. If no thread is found, the work is queued to the proc + * waitqueue. + * + * If the @thread parameter is not NULL, the transaction is always queued + * to the waitlist of that specific thread. + * + * Return: 0 if the transaction was successfully queued + * BR_DEAD_REPLY if the target process or thread is dead + * BR_FROZEN_REPLY if the target process or thread is frozen + */ +static int binder_proc_transaction(struct binder_transaction *t, + struct binder_proc *proc, + struct binder_thread *thread) +{ + struct binder_node *node = t->buffer->target_node; + bool oneway = !!(t->flags & TF_ONE_WAY); + bool pending_async = false; + struct binder_transaction *t_outdated = NULL; + + BUG_ON(!node); + binder_node_lock(node); + if (oneway) { + BUG_ON(thread); + if (node->has_async_transaction) + pending_async = true; + else + node->has_async_transaction = true; + } + + binder_inner_proc_lock(proc); + if (proc->is_frozen) { + proc->sync_recv |= !oneway; + proc->async_recv |= oneway; + } + + if ((proc->is_frozen && !oneway) || proc->is_dead || + (thread && thread->is_dead)) { + binder_inner_proc_unlock(proc); + binder_node_unlock(node); + return proc->is_frozen ? BR_FROZEN_REPLY : BR_DEAD_REPLY; + } + + if (!thread && !pending_async) + thread = binder_select_thread_ilocked(proc); + + if (thread) { + binder_enqueue_thread_work_ilocked(thread, &t->work); + } else if (!pending_async) { + binder_enqueue_work_ilocked(&t->work, &proc->todo); + } else { + if ((t->flags & TF_UPDATE_TXN) && proc->is_frozen) { + t_outdated = binder_find_outdated_transaction_ilocked(t, + &node->async_todo); + if (t_outdated) { + binder_debug(BINDER_DEBUG_TRANSACTION, + "txn %d supersedes %d\n", + t->debug_id, t_outdated->debug_id); + list_del_init(&t_outdated->work.entry); + proc->outstanding_txns--; + } + } + binder_enqueue_work_ilocked(&t->work, &node->async_todo); + } + + if (!pending_async) + binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */); + + proc->outstanding_txns++; + binder_inner_proc_unlock(proc); + binder_node_unlock(node); + + /* + * To reduce potential contention, free the outdated transaction and + * buffer after releasing the locks. + */ + if (t_outdated) { + struct binder_buffer *buffer = t_outdated->buffer; + + t_outdated->buffer = NULL; + buffer->transaction = NULL; + trace_binder_transaction_update_buffer_release(buffer); + binder_release_entire_buffer(proc, NULL, buffer, false); + binder_alloc_free_buf(&proc->alloc, buffer); + kfree(t_outdated); + binder_stats_deleted(BINDER_STAT_TRANSACTION); + } + + return 0; +} + +/** + * binder_get_node_refs_for_txn() - Get required refs on node for txn + * @node: struct binder_node for which to get refs + * @proc: returns @node->proc if valid + * @error: if no @proc then returns BR_DEAD_REPLY + * + * User-space normally keeps the node alive when creating a transaction + * since it has a reference to the target. The local strong ref keeps it + * alive if the sending process dies before the target process processes + * the transaction. If the source process is malicious or has a reference + * counting bug, relying on the local strong ref can fail. + * + * Since user-space can cause the local strong ref to go away, we also take + * a tmpref on the node to ensure it survives while we are constructing + * the transaction. We also need a tmpref on the proc while we are + * constructing the transaction, so we take that here as well. + * + * Return: The target_node with refs taken or NULL if no @node->proc is NULL. + * Also sets @proc if valid. If the @node->proc is NULL indicating that the + * target proc has died, @error is set to BR_DEAD_REPLY + */ +static struct binder_node *binder_get_node_refs_for_txn( + struct binder_node *node, + struct binder_proc **procp, + uint32_t *error) +{ + struct binder_node *target_node = NULL; + + binder_node_inner_lock(node); + if (node->proc) { + target_node = node; + binder_inc_node_nilocked(node, 1, 0, NULL); + binder_inc_node_tmpref_ilocked(node); + node->proc->tmp_ref++; + *procp = node->proc; + } else + *error = BR_DEAD_REPLY; + binder_node_inner_unlock(node); + + return target_node; +} + +static void binder_set_txn_from_error(struct binder_transaction *t, int id, + uint32_t command, int32_t param) +{ + struct binder_thread *from = binder_get_txn_from_and_acq_inner(t); + + if (!from) { + /* annotation for sparse */ + __release(&from->proc->inner_lock); + return; + } + + /* don't override existing errors */ + if (from->ee.command == BR_OK) + binder_set_extended_error(&from->ee, id, command, param); + binder_inner_proc_unlock(from->proc); + binder_thread_dec_tmpref(from); +} + +static void binder_transaction(struct binder_proc *proc, + struct binder_thread *thread, + struct binder_transaction_data *tr, int reply, + binder_size_t extra_buffers_size) +{ + int ret; + struct binder_transaction *t; + struct binder_work *w; + struct binder_work *tcomplete; + binder_size_t buffer_offset = 0; + binder_size_t off_start_offset, off_end_offset; + binder_size_t off_min; + binder_size_t sg_buf_offset, sg_buf_end_offset; + binder_size_t user_offset = 0; + struct binder_proc *target_proc = NULL; + struct binder_thread *target_thread = NULL; + struct binder_node *target_node = NULL; + struct binder_transaction *in_reply_to = NULL; + struct binder_transaction_log_entry *e; + uint32_t return_error = 0; + uint32_t return_error_param = 0; + uint32_t return_error_line = 0; + binder_size_t last_fixup_obj_off = 0; + binder_size_t last_fixup_min_off = 0; + struct binder_context *context = proc->context; + int t_debug_id = atomic_inc_return(&binder_last_id); + char *secctx = NULL; + u32 secctx_sz = 0; + struct list_head sgc_head; + struct list_head pf_head; + const void __user *user_buffer = (const void __user *) + (uintptr_t)tr->data.ptr.buffer; + INIT_LIST_HEAD(&sgc_head); + INIT_LIST_HEAD(&pf_head); + + e = binder_transaction_log_add(&binder_transaction_log); + e->debug_id = t_debug_id; + e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY); + e->from_proc = proc->pid; + e->from_thread = thread->pid; + e->target_handle = tr->target.handle; + e->data_size = tr->data_size; + e->offsets_size = tr->offsets_size; + strscpy(e->context_name, proc->context->name, BINDERFS_MAX_NAME); + + binder_inner_proc_lock(proc); + binder_set_extended_error(&thread->ee, t_debug_id, BR_OK, 0); + binder_inner_proc_unlock(proc); + + if (reply) { + binder_inner_proc_lock(proc); + in_reply_to = thread->transaction_stack; + if (in_reply_to == NULL) { + binder_inner_proc_unlock(proc); + binder_user_error("%d:%d got reply transaction with no transaction stack\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; + goto err_empty_call_stack; + } + if (in_reply_to->to_thread != thread) { + spin_lock(&in_reply_to->lock); + binder_user_error("%d:%d got reply transaction with bad transaction stack, transaction %d has target %d:%d\n", + proc->pid, thread->pid, in_reply_to->debug_id, + in_reply_to->to_proc ? + in_reply_to->to_proc->pid : 0, + in_reply_to->to_thread ? + in_reply_to->to_thread->pid : 0); + spin_unlock(&in_reply_to->lock); + binder_inner_proc_unlock(proc); + return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; + in_reply_to = NULL; + goto err_bad_call_stack; + } + thread->transaction_stack = in_reply_to->to_parent; + binder_inner_proc_unlock(proc); + binder_set_nice(in_reply_to->saved_priority); + target_thread = binder_get_txn_from_and_acq_inner(in_reply_to); + if (target_thread == NULL) { + /* annotation for sparse */ + __release(&target_thread->proc->inner_lock); + binder_txn_error("%d:%d reply target not found\n", + thread->pid, proc->pid); + return_error = BR_DEAD_REPLY; + return_error_line = __LINE__; + goto err_dead_binder; + } + if (target_thread->transaction_stack != in_reply_to) { + binder_user_error("%d:%d got reply transaction with bad target transaction stack %d, expected %d\n", + proc->pid, thread->pid, + target_thread->transaction_stack ? + target_thread->transaction_stack->debug_id : 0, + in_reply_to->debug_id); + binder_inner_proc_unlock(target_thread->proc); + return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; + in_reply_to = NULL; + target_thread = NULL; + goto err_dead_binder; + } + target_proc = target_thread->proc; + target_proc->tmp_ref++; + binder_inner_proc_unlock(target_thread->proc); + } else { + if (tr->target.handle) { + struct binder_ref *ref; + + /* + * There must already be a strong ref + * on this node. If so, do a strong + * increment on the node to ensure it + * stays alive until the transaction is + * done. + */ + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, tr->target.handle, + true); + if (ref) { + target_node = binder_get_node_refs_for_txn( + ref->node, &target_proc, + &return_error); + } else { + binder_user_error("%d:%d got transaction to invalid handle, %u\n", + proc->pid, thread->pid, tr->target.handle); + return_error = BR_FAILED_REPLY; + } + binder_proc_unlock(proc); + } else { + mutex_lock(&context->context_mgr_node_lock); + target_node = context->binder_context_mgr_node; + if (target_node) + target_node = binder_get_node_refs_for_txn( + target_node, &target_proc, + &return_error); + else + return_error = BR_DEAD_REPLY; + mutex_unlock(&context->context_mgr_node_lock); + if (target_node && target_proc->pid == proc->pid) { + binder_user_error("%d:%d got transaction to context manager from process owning it\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_invalid_target_handle; + } + } + if (!target_node) { + binder_txn_error("%d:%d cannot find target node\n", + thread->pid, proc->pid); + /* + * return_error is set above + */ + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_dead_binder; + } + e->to_node = target_node->debug_id; + if (WARN_ON(proc == target_proc)) { + binder_txn_error("%d:%d self transactions not allowed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_invalid_target_handle; + } + if (security_binder_transaction(proc->cred, + target_proc->cred) < 0) { + binder_txn_error("%d:%d transaction credentials failed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EPERM; + return_error_line = __LINE__; + goto err_invalid_target_handle; + } + binder_inner_proc_lock(proc); + + w = list_first_entry_or_null(&thread->todo, + struct binder_work, entry); + if (!(tr->flags & TF_ONE_WAY) && w && + w->type == BINDER_WORK_TRANSACTION) { + /* + * Do not allow new outgoing transaction from a + * thread that has a transaction at the head of + * its todo list. Only need to check the head + * because binder_select_thread_ilocked picks a + * thread from proc->waiting_threads to enqueue + * the transaction, and nothing is queued to the + * todo list while the thread is on waiting_threads. + */ + binder_user_error("%d:%d new transaction not allowed when there is a transaction on thread todo\n", + proc->pid, thread->pid); + binder_inner_proc_unlock(proc); + return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; + goto err_bad_todo_list; + } + + if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) { + struct binder_transaction *tmp; + + tmp = thread->transaction_stack; + if (tmp->to_thread != thread) { + spin_lock(&tmp->lock); + binder_user_error("%d:%d got new transaction with bad transaction stack, transaction %d has target %d:%d\n", + proc->pid, thread->pid, tmp->debug_id, + tmp->to_proc ? tmp->to_proc->pid : 0, + tmp->to_thread ? + tmp->to_thread->pid : 0); + spin_unlock(&tmp->lock); + binder_inner_proc_unlock(proc); + return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; + goto err_bad_call_stack; + } + while (tmp) { + struct binder_thread *from; + + spin_lock(&tmp->lock); + from = tmp->from; + if (from && from->proc == target_proc) { + atomic_inc(&from->tmp_ref); + target_thread = from; + spin_unlock(&tmp->lock); + break; + } + spin_unlock(&tmp->lock); + tmp = tmp->from_parent; + } + } + binder_inner_proc_unlock(proc); + } + if (target_thread) + e->to_thread = target_thread->pid; + e->to_proc = target_proc->pid; + + /* TODO: reuse incoming transaction for reply */ + t = kzalloc(sizeof(*t), GFP_KERNEL); + if (t == NULL) { + binder_txn_error("%d:%d cannot allocate transaction\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -ENOMEM; + return_error_line = __LINE__; + goto err_alloc_t_failed; + } + INIT_LIST_HEAD(&t->fd_fixups); + binder_stats_created(BINDER_STAT_TRANSACTION); + spin_lock_init(&t->lock); + + tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL); + if (tcomplete == NULL) { + binder_txn_error("%d:%d cannot allocate work for transaction\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -ENOMEM; + return_error_line = __LINE__; + goto err_alloc_tcomplete_failed; + } + binder_stats_created(BINDER_STAT_TRANSACTION_COMPLETE); + + t->debug_id = t_debug_id; + + if (reply) + binder_debug(BINDER_DEBUG_TRANSACTION, + "%d:%d BC_REPLY %d -> %d:%d, data %016llx-%016llx size %lld-%lld-%lld\n", + proc->pid, thread->pid, t->debug_id, + target_proc->pid, target_thread->pid, + (u64)tr->data.ptr.buffer, + (u64)tr->data.ptr.offsets, + (u64)tr->data_size, (u64)tr->offsets_size, + (u64)extra_buffers_size); + else + binder_debug(BINDER_DEBUG_TRANSACTION, + "%d:%d BC_TRANSACTION %d -> %d - node %d, data %016llx-%016llx size %lld-%lld-%lld\n", + proc->pid, thread->pid, t->debug_id, + target_proc->pid, target_node->debug_id, + (u64)tr->data.ptr.buffer, + (u64)tr->data.ptr.offsets, + (u64)tr->data_size, (u64)tr->offsets_size, + (u64)extra_buffers_size); + + if (!reply && !(tr->flags & TF_ONE_WAY)) + t->from = thread; + else + t->from = NULL; + t->sender_euid = task_euid(proc->tsk); + t->to_proc = target_proc; + t->to_thread = target_thread; + t->code = tr->code; + t->flags = tr->flags; + t->priority = task_nice(current); + + if (target_node && target_node->txn_security_ctx) { + u32 secid; + size_t added_size; + + security_cred_getsecid(proc->cred, &secid); + ret = security_secid_to_secctx(secid, &secctx, &secctx_sz); + if (ret) { + binder_txn_error("%d:%d failed to get security context\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_get_secctx_failed; + } + added_size = ALIGN(secctx_sz, sizeof(u64)); + extra_buffers_size += added_size; + if (extra_buffers_size < added_size) { + binder_txn_error("%d:%d integer overflow of extra_buffers_size\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_extra_size; + } + } + + trace_binder_transaction(reply, t, target_node); + + t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size, + tr->offsets_size, extra_buffers_size, + !reply && (t->flags & TF_ONE_WAY), current->tgid); + if (IS_ERR(t->buffer)) { + char *s; + + ret = PTR_ERR(t->buffer); + s = (ret == -ESRCH) ? ": vma cleared, target dead or dying" + : (ret == -ENOSPC) ? ": no space left" + : (ret == -ENOMEM) ? ": memory allocation failed" + : ""; + binder_txn_error("cannot allocate buffer%s", s); + + return_error_param = PTR_ERR(t->buffer); + return_error = return_error_param == -ESRCH ? + BR_DEAD_REPLY : BR_FAILED_REPLY; + return_error_line = __LINE__; + t->buffer = NULL; + goto err_binder_alloc_buf_failed; + } + if (secctx) { + int err; + size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) + + ALIGN(tr->offsets_size, sizeof(void *)) + + ALIGN(extra_buffers_size, sizeof(void *)) - + ALIGN(secctx_sz, sizeof(u64)); + + t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset; + err = binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, buf_offset, + secctx, secctx_sz); + if (err) { + t->security_ctx = 0; + WARN_ON(1); + } + security_release_secctx(secctx, secctx_sz); + secctx = NULL; + } + t->buffer->debug_id = t->debug_id; + t->buffer->transaction = t; + t->buffer->target_node = target_node; + t->buffer->clear_on_free = !!(t->flags & TF_CLEAR_BUF); + trace_binder_transaction_alloc_buf(t->buffer); + + if (binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, + ALIGN(tr->data_size, sizeof(void *)), + (const void __user *) + (uintptr_t)tr->data.ptr.offsets, + tr->offsets_size)) { + binder_user_error("%d:%d got transaction with invalid offsets ptr\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EFAULT; + return_error_line = __LINE__; + goto err_copy_data_failed; + } + if (!IS_ALIGNED(tr->offsets_size, sizeof(binder_size_t))) { + binder_user_error("%d:%d got transaction with invalid offsets size, %lld\n", + proc->pid, thread->pid, (u64)tr->offsets_size); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_offset; + } + if (!IS_ALIGNED(extra_buffers_size, sizeof(u64))) { + binder_user_error("%d:%d got transaction with unaligned buffers size, %lld\n", + proc->pid, thread->pid, + (u64)extra_buffers_size); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_offset; + } + off_start_offset = ALIGN(tr->data_size, sizeof(void *)); + buffer_offset = off_start_offset; + off_end_offset = off_start_offset + tr->offsets_size; + sg_buf_offset = ALIGN(off_end_offset, sizeof(void *)); + sg_buf_end_offset = sg_buf_offset + extra_buffers_size - + ALIGN(secctx_sz, sizeof(u64)); + off_min = 0; + for (buffer_offset = off_start_offset; buffer_offset < off_end_offset; + buffer_offset += sizeof(binder_size_t)) { + struct binder_object_header *hdr; + size_t object_size; + struct binder_object object; + binder_size_t object_offset; + binder_size_t copy_size; + + if (binder_alloc_copy_from_buffer(&target_proc->alloc, + &object_offset, + t->buffer, + buffer_offset, + sizeof(object_offset))) { + binder_txn_error("%d:%d copy offset from buffer failed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_offset; + } + + /* + * Copy the source user buffer up to the next object + * that will be processed. + */ + copy_size = object_offset - user_offset; + if (copy_size && (user_offset > object_offset || + binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, user_offset, + user_buffer + user_offset, + copy_size))) { + binder_user_error("%d:%d got transaction with invalid data ptr\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EFAULT; + return_error_line = __LINE__; + goto err_copy_data_failed; + } + object_size = binder_get_object(target_proc, user_buffer, + t->buffer, object_offset, &object); + if (object_size == 0 || object_offset < off_min) { + binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n", + proc->pid, thread->pid, + (u64)object_offset, + (u64)off_min, + (u64)t->buffer->data_size); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_offset; + } + /* + * Set offset to the next buffer fragment to be + * copied + */ + user_offset = object_offset + object_size; + + hdr = &object.hdr; + off_min = object_offset + object_size; + switch (hdr->type) { + case BINDER_TYPE_BINDER: + case BINDER_TYPE_WEAK_BINDER: { + struct flat_binder_object *fp; + + fp = to_flat_binder_object(hdr); + ret = binder_translate_binder(fp, t, thread); + + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fp, sizeof(*fp))) { + binder_txn_error("%d:%d translate binder failed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_translate_failed; + } + } break; + case BINDER_TYPE_HANDLE: + case BINDER_TYPE_WEAK_HANDLE: { + struct flat_binder_object *fp; + + fp = to_flat_binder_object(hdr); + ret = binder_translate_handle(fp, t, thread); + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fp, sizeof(*fp))) { + binder_txn_error("%d:%d translate handle failed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_translate_failed; + } + } break; + + case BINDER_TYPE_FD: { + struct binder_fd_object *fp = to_binder_fd_object(hdr); + binder_size_t fd_offset = object_offset + + (uintptr_t)&fp->fd - (uintptr_t)fp; + int ret = binder_translate_fd(fp->fd, fd_offset, t, + thread, in_reply_to); + + fp->pad_binder = 0; + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fp, sizeof(*fp))) { + binder_txn_error("%d:%d translate fd failed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_translate_failed; + } + } break; + case BINDER_TYPE_FDA: { + struct binder_object ptr_object; + binder_size_t parent_offset; + struct binder_object user_object; + size_t user_parent_size; + struct binder_fd_array_object *fda = + to_binder_fd_array_object(hdr); + size_t num_valid = (buffer_offset - off_start_offset) / + sizeof(binder_size_t); + struct binder_buffer_object *parent = + binder_validate_ptr(target_proc, t->buffer, + &ptr_object, fda->parent, + off_start_offset, + &parent_offset, + num_valid); + if (!parent) { + binder_user_error("%d:%d got transaction with invalid parent offset or type\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_parent; + } + if (!binder_validate_fixup(target_proc, t->buffer, + off_start_offset, + parent_offset, + fda->parent_offset, + last_fixup_obj_off, + last_fixup_min_off)) { + binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_parent; + } + /* + * We need to read the user version of the parent + * object to get the original user offset + */ + user_parent_size = + binder_get_object(proc, user_buffer, t->buffer, + parent_offset, &user_object); + if (user_parent_size != sizeof(user_object.bbo)) { + binder_user_error("%d:%d invalid ptr object size: %zd vs %zd\n", + proc->pid, thread->pid, + user_parent_size, + sizeof(user_object.bbo)); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_parent; + } + ret = binder_translate_fd_array(&pf_head, fda, + user_buffer, parent, + &user_object.bbo, t, + thread, in_reply_to); + if (!ret) + ret = binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fda, sizeof(*fda)); + if (ret) { + binder_txn_error("%d:%d translate fd array failed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret > 0 ? -EINVAL : ret; + return_error_line = __LINE__; + goto err_translate_failed; + } + last_fixup_obj_off = parent_offset; + last_fixup_min_off = + fda->parent_offset + sizeof(u32) * fda->num_fds; + } break; + case BINDER_TYPE_PTR: { + struct binder_buffer_object *bp = + to_binder_buffer_object(hdr); + size_t buf_left = sg_buf_end_offset - sg_buf_offset; + size_t num_valid; + + if (bp->length > buf_left) { + binder_user_error("%d:%d got transaction with too large buffer\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_offset; + } + ret = binder_defer_copy(&sgc_head, sg_buf_offset, + (const void __user *)(uintptr_t)bp->buffer, + bp->length); + if (ret) { + binder_txn_error("%d:%d deferred copy failed\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_translate_failed; + } + /* Fixup buffer pointer to target proc address space */ + bp->buffer = (uintptr_t) + t->buffer->user_data + sg_buf_offset; + sg_buf_offset += ALIGN(bp->length, sizeof(u64)); + + num_valid = (buffer_offset - off_start_offset) / + sizeof(binder_size_t); + ret = binder_fixup_parent(&pf_head, t, + thread, bp, + off_start_offset, + num_valid, + last_fixup_obj_off, + last_fixup_min_off); + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + bp, sizeof(*bp))) { + binder_txn_error("%d:%d failed to fixup parent\n", + thread->pid, proc->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_translate_failed; + } + last_fixup_obj_off = object_offset; + last_fixup_min_off = 0; + } break; + default: + binder_user_error("%d:%d got transaction with invalid object type, %x\n", + proc->pid, thread->pid, hdr->type); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_object_type; + } + } + /* Done processing objects, copy the rest of the buffer */ + if (binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, user_offset, + user_buffer + user_offset, + tr->data_size - user_offset)) { + binder_user_error("%d:%d got transaction with invalid data ptr\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EFAULT; + return_error_line = __LINE__; + goto err_copy_data_failed; + } + + ret = binder_do_deferred_txn_copies(&target_proc->alloc, t->buffer, + &sgc_head, &pf_head); + if (ret) { + binder_user_error("%d:%d got transaction with invalid offsets ptr\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_copy_data_failed; + } + if (t->buffer->oneway_spam_suspect) + tcomplete->type = BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT; + else + tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; + t->work.type = BINDER_WORK_TRANSACTION; + + if (reply) { + binder_enqueue_thread_work(thread, tcomplete); + binder_inner_proc_lock(target_proc); + if (target_thread->is_dead) { + return_error = BR_DEAD_REPLY; + binder_inner_proc_unlock(target_proc); + goto err_dead_proc_or_thread; + } + BUG_ON(t->buffer->async_transaction != 0); + binder_pop_transaction_ilocked(target_thread, in_reply_to); + binder_enqueue_thread_work_ilocked(target_thread, &t->work); + target_proc->outstanding_txns++; + binder_inner_proc_unlock(target_proc); + wake_up_interruptible_sync(&target_thread->wait); + binder_free_transaction(in_reply_to); + } else if (!(t->flags & TF_ONE_WAY)) { + BUG_ON(t->buffer->async_transaction != 0); + binder_inner_proc_lock(proc); + /* + * Defer the TRANSACTION_COMPLETE, so we don't return to + * userspace immediately; this allows the target process to + * immediately start processing this transaction, reducing + * latency. We will then return the TRANSACTION_COMPLETE when + * the target replies (or there is an error). + */ + binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete); + t->need_reply = 1; + t->from_parent = thread->transaction_stack; + thread->transaction_stack = t; + binder_inner_proc_unlock(proc); + return_error = binder_proc_transaction(t, + target_proc, target_thread); + if (return_error) { + binder_inner_proc_lock(proc); + binder_pop_transaction_ilocked(thread, t); + binder_inner_proc_unlock(proc); + goto err_dead_proc_or_thread; + } + } else { + BUG_ON(target_node == NULL); + BUG_ON(t->buffer->async_transaction != 1); + binder_enqueue_thread_work(thread, tcomplete); + return_error = binder_proc_transaction(t, target_proc, NULL); + if (return_error) + goto err_dead_proc_or_thread; + } + if (target_thread) + binder_thread_dec_tmpref(target_thread); + binder_proc_dec_tmpref(target_proc); + if (target_node) + binder_dec_node_tmpref(target_node); + /* + * write barrier to synchronize with initialization + * of log entry + */ + smp_wmb(); + WRITE_ONCE(e->debug_id_done, t_debug_id); + return; + +err_dead_proc_or_thread: + binder_txn_error("%d:%d dead process or thread\n", + thread->pid, proc->pid); + return_error_line = __LINE__; + binder_dequeue_work(proc, tcomplete); +err_translate_failed: +err_bad_object_type: +err_bad_offset: +err_bad_parent: +err_copy_data_failed: + binder_cleanup_deferred_txn_lists(&sgc_head, &pf_head); + binder_free_txn_fixups(t); + trace_binder_transaction_failed_buffer_release(t->buffer); + binder_transaction_buffer_release(target_proc, NULL, t->buffer, + buffer_offset, true); + if (target_node) + binder_dec_node_tmpref(target_node); + target_node = NULL; + t->buffer->transaction = NULL; + binder_alloc_free_buf(&target_proc->alloc, t->buffer); +err_binder_alloc_buf_failed: +err_bad_extra_size: + if (secctx) + security_release_secctx(secctx, secctx_sz); +err_get_secctx_failed: + kfree(tcomplete); + binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE); +err_alloc_tcomplete_failed: + if (trace_binder_txn_latency_free_enabled()) + binder_txn_latency_free(t); + kfree(t); + binder_stats_deleted(BINDER_STAT_TRANSACTION); +err_alloc_t_failed: +err_bad_todo_list: +err_bad_call_stack: +err_empty_call_stack: +err_dead_binder: +err_invalid_target_handle: + if (target_node) { + binder_dec_node(target_node, 1, 0); + binder_dec_node_tmpref(target_node); + } + + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, + "%d:%d transaction %s to %d:%d failed %d/%d/%d, size %lld-%lld line %d\n", + proc->pid, thread->pid, reply ? "reply" : + (tr->flags & TF_ONE_WAY ? "async" : "call"), + target_proc ? target_proc->pid : 0, + target_thread ? target_thread->pid : 0, + t_debug_id, return_error, return_error_param, + (u64)tr->data_size, (u64)tr->offsets_size, + return_error_line); + + if (target_thread) + binder_thread_dec_tmpref(target_thread); + if (target_proc) + binder_proc_dec_tmpref(target_proc); + + { + struct binder_transaction_log_entry *fe; + + e->return_error = return_error; + e->return_error_param = return_error_param; + e->return_error_line = return_error_line; + fe = binder_transaction_log_add(&binder_transaction_log_failed); + *fe = *e; + /* + * write barrier to synchronize with initialization + * of log entry + */ + smp_wmb(); + WRITE_ONCE(e->debug_id_done, t_debug_id); + WRITE_ONCE(fe->debug_id_done, t_debug_id); + } + + BUG_ON(thread->return_error.cmd != BR_OK); + if (in_reply_to) { + binder_set_txn_from_error(in_reply_to, t_debug_id, + return_error, return_error_param); + thread->return_error.cmd = BR_TRANSACTION_COMPLETE; + binder_enqueue_thread_work(thread, &thread->return_error.work); + binder_send_failed_reply(in_reply_to, return_error); + } else { + binder_inner_proc_lock(proc); + binder_set_extended_error(&thread->ee, t_debug_id, + return_error, return_error_param); + binder_inner_proc_unlock(proc); + thread->return_error.cmd = return_error; + binder_enqueue_thread_work(thread, &thread->return_error.work); + } +} + +/** + * binder_free_buf() - free the specified buffer + * @proc: binder proc that owns buffer + * @buffer: buffer to be freed + * @is_failure: failed to send transaction + * + * If buffer for an async transaction, enqueue the next async + * transaction from the node. + * + * Cleanup buffer and free it. + */ +static void +binder_free_buf(struct binder_proc *proc, + struct binder_thread *thread, + struct binder_buffer *buffer, bool is_failure) +{ + binder_inner_proc_lock(proc); + if (buffer->transaction) { + buffer->transaction->buffer = NULL; + buffer->transaction = NULL; + } + binder_inner_proc_unlock(proc); + if (buffer->async_transaction && buffer->target_node) { + struct binder_node *buf_node; + struct binder_work *w; + + buf_node = buffer->target_node; + binder_node_inner_lock(buf_node); + BUG_ON(!buf_node->has_async_transaction); + BUG_ON(buf_node->proc != proc); + w = binder_dequeue_work_head_ilocked( + &buf_node->async_todo); + if (!w) { + buf_node->has_async_transaction = false; + } else { + binder_enqueue_work_ilocked( + w, &proc->todo); + binder_wakeup_proc_ilocked(proc); + } + binder_node_inner_unlock(buf_node); + } + trace_binder_transaction_buffer_release(buffer); + binder_release_entire_buffer(proc, thread, buffer, is_failure); + binder_alloc_free_buf(&proc->alloc, buffer); +} + +static int binder_thread_write(struct binder_proc *proc, + struct binder_thread *thread, + binder_uintptr_t binder_buffer, size_t size, + binder_size_t *consumed) +{ + uint32_t cmd; + struct binder_context *context = proc->context; + void __user *buffer = (void __user *)(uintptr_t)binder_buffer; + void __user *ptr = buffer + *consumed; + void __user *end = buffer + size; + + while (ptr < end && thread->return_error.cmd == BR_OK) { + int ret; + + if (get_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + trace_binder_command(cmd); + if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) { + atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]); + atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]); + atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]); + } + switch (cmd) { + case BC_INCREFS: + case BC_ACQUIRE: + case BC_RELEASE: + case BC_DECREFS: { + uint32_t target; + const char *debug_string; + bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE; + bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE; + struct binder_ref_data rdata; + + if (get_user(target, (uint32_t __user *)ptr)) + return -EFAULT; + + ptr += sizeof(uint32_t); + ret = -1; + if (increment && !target) { + struct binder_node *ctx_mgr_node; + + mutex_lock(&context->context_mgr_node_lock); + ctx_mgr_node = context->binder_context_mgr_node; + if (ctx_mgr_node) { + if (ctx_mgr_node->proc == proc) { + binder_user_error("%d:%d context manager tried to acquire desc 0\n", + proc->pid, thread->pid); + mutex_unlock(&context->context_mgr_node_lock); + return -EINVAL; + } + ret = binder_inc_ref_for_node( + proc, ctx_mgr_node, + strong, NULL, &rdata); + } + mutex_unlock(&context->context_mgr_node_lock); + } + if (ret) + ret = binder_update_ref_for_handle( + proc, target, increment, strong, + &rdata); + if (!ret && rdata.desc != target) { + binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n", + proc->pid, thread->pid, + target, rdata.desc); + } + switch (cmd) { + case BC_INCREFS: + debug_string = "IncRefs"; + break; + case BC_ACQUIRE: + debug_string = "Acquire"; + break; + case BC_RELEASE: + debug_string = "Release"; + break; + case BC_DECREFS: + default: + debug_string = "DecRefs"; + break; + } + if (ret) { + binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n", + proc->pid, thread->pid, debug_string, + strong, target, ret); + break; + } + binder_debug(BINDER_DEBUG_USER_REFS, + "%d:%d %s ref %d desc %d s %d w %d\n", + proc->pid, thread->pid, debug_string, + rdata.debug_id, rdata.desc, rdata.strong, + rdata.weak); + break; + } + case BC_INCREFS_DONE: + case BC_ACQUIRE_DONE: { + binder_uintptr_t node_ptr; + binder_uintptr_t cookie; + struct binder_node *node; + bool free_node; + + if (get_user(node_ptr, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + if (get_user(cookie, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + node = binder_get_node(proc, node_ptr); + if (node == NULL) { + binder_user_error("%d:%d %s u%016llx no match\n", + proc->pid, thread->pid, + cmd == BC_INCREFS_DONE ? + "BC_INCREFS_DONE" : + "BC_ACQUIRE_DONE", + (u64)node_ptr); + break; + } + if (cookie != node->cookie) { + binder_user_error("%d:%d %s u%016llx node %d cookie mismatch %016llx != %016llx\n", + proc->pid, thread->pid, + cmd == BC_INCREFS_DONE ? + "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE", + (u64)node_ptr, node->debug_id, + (u64)cookie, (u64)node->cookie); + binder_put_node(node); + break; + } + binder_node_inner_lock(node); + if (cmd == BC_ACQUIRE_DONE) { + if (node->pending_strong_ref == 0) { + binder_user_error("%d:%d BC_ACQUIRE_DONE node %d has no pending acquire request\n", + proc->pid, thread->pid, + node->debug_id); + binder_node_inner_unlock(node); + binder_put_node(node); + break; + } + node->pending_strong_ref = 0; + } else { + if (node->pending_weak_ref == 0) { + binder_user_error("%d:%d BC_INCREFS_DONE node %d has no pending increfs request\n", + proc->pid, thread->pid, + node->debug_id); + binder_node_inner_unlock(node); + binder_put_node(node); + break; + } + node->pending_weak_ref = 0; + } + free_node = binder_dec_node_nilocked(node, + cmd == BC_ACQUIRE_DONE, 0); + WARN_ON(free_node); + binder_debug(BINDER_DEBUG_USER_REFS, + "%d:%d %s node %d ls %d lw %d tr %d\n", + proc->pid, thread->pid, + cmd == BC_INCREFS_DONE ? "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE", + node->debug_id, node->local_strong_refs, + node->local_weak_refs, node->tmp_refs); + binder_node_inner_unlock(node); + binder_put_node(node); + break; + } + case BC_ATTEMPT_ACQUIRE: + pr_err("BC_ATTEMPT_ACQUIRE not supported\n"); + return -EINVAL; + case BC_ACQUIRE_RESULT: + pr_err("BC_ACQUIRE_RESULT not supported\n"); + return -EINVAL; + + case BC_FREE_BUFFER: { + binder_uintptr_t data_ptr; + struct binder_buffer *buffer; + + if (get_user(data_ptr, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + + buffer = binder_alloc_prepare_to_free(&proc->alloc, + data_ptr); + if (IS_ERR_OR_NULL(buffer)) { + if (PTR_ERR(buffer) == -EPERM) { + binder_user_error( + "%d:%d BC_FREE_BUFFER u%016llx matched unreturned or currently freeing buffer\n", + proc->pid, thread->pid, + (u64)data_ptr); + } else { + binder_user_error( + "%d:%d BC_FREE_BUFFER u%016llx no match\n", + proc->pid, thread->pid, + (u64)data_ptr); + } + break; + } + binder_debug(BINDER_DEBUG_FREE_BUFFER, + "%d:%d BC_FREE_BUFFER u%016llx found buffer %d for %s transaction\n", + proc->pid, thread->pid, (u64)data_ptr, + buffer->debug_id, + buffer->transaction ? "active" : "finished"); + binder_free_buf(proc, thread, buffer, false); + break; + } + + case BC_TRANSACTION_SG: + case BC_REPLY_SG: { + struct binder_transaction_data_sg tr; + + if (copy_from_user(&tr, ptr, sizeof(tr))) + return -EFAULT; + ptr += sizeof(tr); + binder_transaction(proc, thread, &tr.transaction_data, + cmd == BC_REPLY_SG, tr.buffers_size); + break; + } + case BC_TRANSACTION: + case BC_REPLY: { + struct binder_transaction_data tr; + + if (copy_from_user(&tr, ptr, sizeof(tr))) + return -EFAULT; + ptr += sizeof(tr); + binder_transaction(proc, thread, &tr, + cmd == BC_REPLY, 0); + break; + } + + case BC_REGISTER_LOOPER: + binder_debug(BINDER_DEBUG_THREADS, + "%d:%d BC_REGISTER_LOOPER\n", + proc->pid, thread->pid); + binder_inner_proc_lock(proc); + if (thread->looper & BINDER_LOOPER_STATE_ENTERED) { + thread->looper |= BINDER_LOOPER_STATE_INVALID; + binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called after BC_ENTER_LOOPER\n", + proc->pid, thread->pid); + } else if (proc->requested_threads == 0) { + thread->looper |= BINDER_LOOPER_STATE_INVALID; + binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called without request\n", + proc->pid, thread->pid); + } else { + proc->requested_threads--; + proc->requested_threads_started++; + } + thread->looper |= BINDER_LOOPER_STATE_REGISTERED; + binder_inner_proc_unlock(proc); + break; + case BC_ENTER_LOOPER: + binder_debug(BINDER_DEBUG_THREADS, + "%d:%d BC_ENTER_LOOPER\n", + proc->pid, thread->pid); + if (thread->looper & BINDER_LOOPER_STATE_REGISTERED) { + thread->looper |= BINDER_LOOPER_STATE_INVALID; + binder_user_error("%d:%d ERROR: BC_ENTER_LOOPER called after BC_REGISTER_LOOPER\n", + proc->pid, thread->pid); + } + thread->looper |= BINDER_LOOPER_STATE_ENTERED; + break; + case BC_EXIT_LOOPER: + binder_debug(BINDER_DEBUG_THREADS, + "%d:%d BC_EXIT_LOOPER\n", + proc->pid, thread->pid); + thread->looper |= BINDER_LOOPER_STATE_EXITED; + break; + + case BC_REQUEST_DEATH_NOTIFICATION: + case BC_CLEAR_DEATH_NOTIFICATION: { + uint32_t target; + binder_uintptr_t cookie; + struct binder_ref *ref; + struct binder_ref_death *death = NULL; + + if (get_user(target, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + if (get_user(cookie, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + if (cmd == BC_REQUEST_DEATH_NOTIFICATION) { + /* + * Allocate memory for death notification + * before taking lock + */ + death = kzalloc(sizeof(*death), GFP_KERNEL); + if (death == NULL) { + WARN_ON(thread->return_error.cmd != + BR_OK); + thread->return_error.cmd = BR_ERROR; + binder_enqueue_thread_work( + thread, + &thread->return_error.work); + binder_debug( + BINDER_DEBUG_FAILED_TRANSACTION, + "%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n", + proc->pid, thread->pid); + break; + } + } + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, target, false); + if (ref == NULL) { + binder_user_error("%d:%d %s invalid ref %d\n", + proc->pid, thread->pid, + cmd == BC_REQUEST_DEATH_NOTIFICATION ? + "BC_REQUEST_DEATH_NOTIFICATION" : + "BC_CLEAR_DEATH_NOTIFICATION", + target); + binder_proc_unlock(proc); + kfree(death); + break; + } + + binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION, + "%d:%d %s %016llx ref %d desc %d s %d w %d for node %d\n", + proc->pid, thread->pid, + cmd == BC_REQUEST_DEATH_NOTIFICATION ? + "BC_REQUEST_DEATH_NOTIFICATION" : + "BC_CLEAR_DEATH_NOTIFICATION", + (u64)cookie, ref->data.debug_id, + ref->data.desc, ref->data.strong, + ref->data.weak, ref->node->debug_id); + + binder_node_lock(ref->node); + if (cmd == BC_REQUEST_DEATH_NOTIFICATION) { + if (ref->death) { + binder_user_error("%d:%d BC_REQUEST_DEATH_NOTIFICATION death notification already set\n", + proc->pid, thread->pid); + binder_node_unlock(ref->node); + binder_proc_unlock(proc); + kfree(death); + break; + } + binder_stats_created(BINDER_STAT_DEATH); + INIT_LIST_HEAD(&death->work.entry); + death->cookie = cookie; + ref->death = death; + if (ref->node->proc == NULL) { + ref->death->work.type = BINDER_WORK_DEAD_BINDER; + + binder_inner_proc_lock(proc); + binder_enqueue_work_ilocked( + &ref->death->work, &proc->todo); + binder_wakeup_proc_ilocked(proc); + binder_inner_proc_unlock(proc); + } + } else { + if (ref->death == NULL) { + binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification not active\n", + proc->pid, thread->pid); + binder_node_unlock(ref->node); + binder_proc_unlock(proc); + break; + } + death = ref->death; + if (death->cookie != cookie) { + binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification cookie mismatch %016llx != %016llx\n", + proc->pid, thread->pid, + (u64)death->cookie, + (u64)cookie); + binder_node_unlock(ref->node); + binder_proc_unlock(proc); + break; + } + ref->death = NULL; + binder_inner_proc_lock(proc); + if (list_empty(&death->work.entry)) { + death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION; + if (thread->looper & + (BINDER_LOOPER_STATE_REGISTERED | + BINDER_LOOPER_STATE_ENTERED)) + binder_enqueue_thread_work_ilocked( + thread, + &death->work); + else { + binder_enqueue_work_ilocked( + &death->work, + &proc->todo); + binder_wakeup_proc_ilocked( + proc); + } + } else { + BUG_ON(death->work.type != BINDER_WORK_DEAD_BINDER); + death->work.type = BINDER_WORK_DEAD_BINDER_AND_CLEAR; + } + binder_inner_proc_unlock(proc); + } + binder_node_unlock(ref->node); + binder_proc_unlock(proc); + } break; + case BC_DEAD_BINDER_DONE: { + struct binder_work *w; + binder_uintptr_t cookie; + struct binder_ref_death *death = NULL; + + if (get_user(cookie, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + + ptr += sizeof(cookie); + binder_inner_proc_lock(proc); + list_for_each_entry(w, &proc->delivered_death, + entry) { + struct binder_ref_death *tmp_death = + container_of(w, + struct binder_ref_death, + work); + + if (tmp_death->cookie == cookie) { + death = tmp_death; + break; + } + } + binder_debug(BINDER_DEBUG_DEAD_BINDER, + "%d:%d BC_DEAD_BINDER_DONE %016llx found %pK\n", + proc->pid, thread->pid, (u64)cookie, + death); + if (death == NULL) { + binder_user_error("%d:%d BC_DEAD_BINDER_DONE %016llx not found\n", + proc->pid, thread->pid, (u64)cookie); + binder_inner_proc_unlock(proc); + break; + } + binder_dequeue_work_ilocked(&death->work); + if (death->work.type == BINDER_WORK_DEAD_BINDER_AND_CLEAR) { + death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION; + if (thread->looper & + (BINDER_LOOPER_STATE_REGISTERED | + BINDER_LOOPER_STATE_ENTERED)) + binder_enqueue_thread_work_ilocked( + thread, &death->work); + else { + binder_enqueue_work_ilocked( + &death->work, + &proc->todo); + binder_wakeup_proc_ilocked(proc); + } + } + binder_inner_proc_unlock(proc); + } break; + + default: + pr_err("%d:%d unknown command %u\n", + proc->pid, thread->pid, cmd); + return -EINVAL; + } + *consumed = ptr - buffer; + } + return 0; +} + +static void binder_stat_br(struct binder_proc *proc, + struct binder_thread *thread, uint32_t cmd) +{ + trace_binder_return(cmd); + if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) { + atomic_inc(&binder_stats.br[_IOC_NR(cmd)]); + atomic_inc(&proc->stats.br[_IOC_NR(cmd)]); + atomic_inc(&thread->stats.br[_IOC_NR(cmd)]); + } +} + +static int binder_put_node_cmd(struct binder_proc *proc, + struct binder_thread *thread, + void __user **ptrp, + binder_uintptr_t node_ptr, + binder_uintptr_t node_cookie, + int node_debug_id, + uint32_t cmd, const char *cmd_name) +{ + void __user *ptr = *ptrp; + + if (put_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + + if (put_user(node_ptr, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + + if (put_user(node_cookie, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + + binder_stat_br(proc, thread, cmd); + binder_debug(BINDER_DEBUG_USER_REFS, "%d:%d %s %d u%016llx c%016llx\n", + proc->pid, thread->pid, cmd_name, node_debug_id, + (u64)node_ptr, (u64)node_cookie); + + *ptrp = ptr; + return 0; +} + +static int binder_wait_for_work(struct binder_thread *thread, + bool do_proc_work) +{ + DEFINE_WAIT(wait); + struct binder_proc *proc = thread->proc; + int ret = 0; + + binder_inner_proc_lock(proc); + for (;;) { + prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE|TASK_FREEZABLE); + if (binder_has_work_ilocked(thread, do_proc_work)) + break; + if (do_proc_work) + list_add(&thread->waiting_thread_node, + &proc->waiting_threads); + binder_inner_proc_unlock(proc); + schedule(); + binder_inner_proc_lock(proc); + list_del_init(&thread->waiting_thread_node); + if (signal_pending(current)) { + ret = -EINTR; + break; + } + } + finish_wait(&thread->wait, &wait); + binder_inner_proc_unlock(proc); + + return ret; +} + +/** + * binder_apply_fd_fixups() - finish fd translation + * @proc: binder_proc associated @t->buffer + * @t: binder transaction with list of fd fixups + * + * Now that we are in the context of the transaction target + * process, we can allocate and install fds. Process the + * list of fds to translate and fixup the buffer with the + * new fds first and only then install the files. + * + * If we fail to allocate an fd, skip the install and release + * any fds that have already been allocated. + */ +static int binder_apply_fd_fixups(struct binder_proc *proc, + struct binder_transaction *t) +{ + struct binder_txn_fd_fixup *fixup, *tmp; + int ret = 0; + + list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) { + int fd = get_unused_fd_flags(O_CLOEXEC); + + if (fd < 0) { + binder_debug(BINDER_DEBUG_TRANSACTION, + "failed fd fixup txn %d fd %d\n", + t->debug_id, fd); + ret = -ENOMEM; + goto err; + } + binder_debug(BINDER_DEBUG_TRANSACTION, + "fd fixup txn %d fd %d\n", + t->debug_id, fd); + trace_binder_transaction_fd_recv(t, fd, fixup->offset); + fixup->target_fd = fd; + if (binder_alloc_copy_to_buffer(&proc->alloc, t->buffer, + fixup->offset, &fd, + sizeof(u32))) { + ret = -EINVAL; + goto err; + } + } + list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) { + fd_install(fixup->target_fd, fixup->file); + list_del(&fixup->fixup_entry); + kfree(fixup); + } + + return ret; + +err: + binder_free_txn_fixups(t); + return ret; +} + +static int binder_thread_read(struct binder_proc *proc, + struct binder_thread *thread, + binder_uintptr_t binder_buffer, size_t size, + binder_size_t *consumed, int non_block) +{ + void __user *buffer = (void __user *)(uintptr_t)binder_buffer; + void __user *ptr = buffer + *consumed; + void __user *end = buffer + size; + + int ret = 0; + int wait_for_proc_work; + + if (*consumed == 0) { + if (put_user(BR_NOOP, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + } + +retry: + binder_inner_proc_lock(proc); + wait_for_proc_work = binder_available_for_proc_work_ilocked(thread); + binder_inner_proc_unlock(proc); + + thread->looper |= BINDER_LOOPER_STATE_WAITING; + + trace_binder_wait_for_work(wait_for_proc_work, + !!thread->transaction_stack, + !binder_worklist_empty(proc, &thread->todo)); + if (wait_for_proc_work) { + if (!(thread->looper & (BINDER_LOOPER_STATE_REGISTERED | + BINDER_LOOPER_STATE_ENTERED))) { + binder_user_error("%d:%d ERROR: Thread waiting for process work before calling BC_REGISTER_LOOPER or BC_ENTER_LOOPER (state %x)\n", + proc->pid, thread->pid, thread->looper); + wait_event_interruptible(binder_user_error_wait, + binder_stop_on_user_error < 2); + } + binder_set_nice(proc->default_priority); + } + + if (non_block) { + if (!binder_has_work(thread, wait_for_proc_work)) + ret = -EAGAIN; + } else { + ret = binder_wait_for_work(thread, wait_for_proc_work); + } + + thread->looper &= ~BINDER_LOOPER_STATE_WAITING; + + if (ret) + return ret; + + while (1) { + uint32_t cmd; + struct binder_transaction_data_secctx tr; + struct binder_transaction_data *trd = &tr.transaction_data; + struct binder_work *w = NULL; + struct list_head *list = NULL; + struct binder_transaction *t = NULL; + struct binder_thread *t_from; + size_t trsize = sizeof(*trd); + + binder_inner_proc_lock(proc); + if (!binder_worklist_empty_ilocked(&thread->todo)) + list = &thread->todo; + else if (!binder_worklist_empty_ilocked(&proc->todo) && + wait_for_proc_work) + list = &proc->todo; + else { + binder_inner_proc_unlock(proc); + + /* no data added */ + if (ptr - buffer == 4 && !thread->looper_need_return) + goto retry; + break; + } + + if (end - ptr < sizeof(tr) + 4) { + binder_inner_proc_unlock(proc); + break; + } + w = binder_dequeue_work_head_ilocked(list); + if (binder_worklist_empty_ilocked(&thread->todo)) + thread->process_todo = false; + + switch (w->type) { + case BINDER_WORK_TRANSACTION: { + binder_inner_proc_unlock(proc); + t = container_of(w, struct binder_transaction, work); + } break; + case BINDER_WORK_RETURN_ERROR: { + struct binder_error *e = container_of( + w, struct binder_error, work); + + WARN_ON(e->cmd == BR_OK); + binder_inner_proc_unlock(proc); + if (put_user(e->cmd, (uint32_t __user *)ptr)) + return -EFAULT; + cmd = e->cmd; + e->cmd = BR_OK; + ptr += sizeof(uint32_t); + + binder_stat_br(proc, thread, cmd); + } break; + case BINDER_WORK_TRANSACTION_COMPLETE: + case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: { + if (proc->oneway_spam_detection_enabled && + w->type == BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT) + cmd = BR_ONEWAY_SPAM_SUSPECT; + else + cmd = BR_TRANSACTION_COMPLETE; + binder_inner_proc_unlock(proc); + kfree(w); + binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE); + if (put_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + + binder_stat_br(proc, thread, cmd); + binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE, + "%d:%d BR_TRANSACTION_COMPLETE\n", + proc->pid, thread->pid); + } break; + case BINDER_WORK_NODE: { + struct binder_node *node = container_of(w, struct binder_node, work); + int strong, weak; + binder_uintptr_t node_ptr = node->ptr; + binder_uintptr_t node_cookie = node->cookie; + int node_debug_id = node->debug_id; + int has_weak_ref; + int has_strong_ref; + void __user *orig_ptr = ptr; + + BUG_ON(proc != node->proc); + strong = node->internal_strong_refs || + node->local_strong_refs; + weak = !hlist_empty(&node->refs) || + node->local_weak_refs || + node->tmp_refs || strong; + has_strong_ref = node->has_strong_ref; + has_weak_ref = node->has_weak_ref; + + if (weak && !has_weak_ref) { + node->has_weak_ref = 1; + node->pending_weak_ref = 1; + node->local_weak_refs++; + } + if (strong && !has_strong_ref) { + node->has_strong_ref = 1; + node->pending_strong_ref = 1; + node->local_strong_refs++; + } + if (!strong && has_strong_ref) + node->has_strong_ref = 0; + if (!weak && has_weak_ref) + node->has_weak_ref = 0; + if (!weak && !strong) { + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d:%d node %d u%016llx c%016llx deleted\n", + proc->pid, thread->pid, + node_debug_id, + (u64)node_ptr, + (u64)node_cookie); + rb_erase(&node->rb_node, &proc->nodes); + binder_inner_proc_unlock(proc); + binder_node_lock(node); + /* + * Acquire the node lock before freeing the + * node to serialize with other threads that + * may have been holding the node lock while + * decrementing this node (avoids race where + * this thread frees while the other thread + * is unlocking the node after the final + * decrement) + */ + binder_node_unlock(node); + binder_free_node(node); + } else + binder_inner_proc_unlock(proc); + + if (weak && !has_weak_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_INCREFS, "BR_INCREFS"); + if (!ret && strong && !has_strong_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_ACQUIRE, "BR_ACQUIRE"); + if (!ret && !strong && has_strong_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_RELEASE, "BR_RELEASE"); + if (!ret && !weak && has_weak_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_DECREFS, "BR_DECREFS"); + if (orig_ptr == ptr) + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d:%d node %d u%016llx c%016llx state unchanged\n", + proc->pid, thread->pid, + node_debug_id, + (u64)node_ptr, + (u64)node_cookie); + if (ret) + return ret; + } break; + case BINDER_WORK_DEAD_BINDER: + case BINDER_WORK_DEAD_BINDER_AND_CLEAR: + case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: { + struct binder_ref_death *death; + uint32_t cmd; + binder_uintptr_t cookie; + + death = container_of(w, struct binder_ref_death, work); + if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) + cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE; + else + cmd = BR_DEAD_BINDER; + cookie = death->cookie; + + binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION, + "%d:%d %s %016llx\n", + proc->pid, thread->pid, + cmd == BR_DEAD_BINDER ? + "BR_DEAD_BINDER" : + "BR_CLEAR_DEATH_NOTIFICATION_DONE", + (u64)cookie); + if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) { + binder_inner_proc_unlock(proc); + kfree(death); + binder_stats_deleted(BINDER_STAT_DEATH); + } else { + binder_enqueue_work_ilocked( + w, &proc->delivered_death); + binder_inner_proc_unlock(proc); + } + if (put_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + if (put_user(cookie, + (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + binder_stat_br(proc, thread, cmd); + if (cmd == BR_DEAD_BINDER) + goto done; /* DEAD_BINDER notifications can cause transactions */ + } break; + default: + binder_inner_proc_unlock(proc); + pr_err("%d:%d: bad work type %d\n", + proc->pid, thread->pid, w->type); + break; + } + + if (!t) + continue; + + BUG_ON(t->buffer == NULL); + if (t->buffer->target_node) { + struct binder_node *target_node = t->buffer->target_node; + + trd->target.ptr = target_node->ptr; + trd->cookie = target_node->cookie; + t->saved_priority = task_nice(current); + if (t->priority < target_node->min_priority && + !(t->flags & TF_ONE_WAY)) + binder_set_nice(t->priority); + else if (!(t->flags & TF_ONE_WAY) || + t->saved_priority > target_node->min_priority) + binder_set_nice(target_node->min_priority); + cmd = BR_TRANSACTION; + } else { + trd->target.ptr = 0; + trd->cookie = 0; + cmd = BR_REPLY; + } + trd->code = t->code; + trd->flags = t->flags; + trd->sender_euid = from_kuid(current_user_ns(), t->sender_euid); + + t_from = binder_get_txn_from(t); + if (t_from) { + struct task_struct *sender = t_from->proc->tsk; + + trd->sender_pid = + task_tgid_nr_ns(sender, + task_active_pid_ns(current)); + } else { + trd->sender_pid = 0; + } + + ret = binder_apply_fd_fixups(proc, t); + if (ret) { + struct binder_buffer *buffer = t->buffer; + bool oneway = !!(t->flags & TF_ONE_WAY); + int tid = t->debug_id; + + if (t_from) + binder_thread_dec_tmpref(t_from); + buffer->transaction = NULL; + binder_cleanup_transaction(t, "fd fixups failed", + BR_FAILED_REPLY); + binder_free_buf(proc, thread, buffer, true); + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, + "%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n", + proc->pid, thread->pid, + oneway ? "async " : + (cmd == BR_REPLY ? "reply " : ""), + tid, BR_FAILED_REPLY, ret, __LINE__); + if (cmd == BR_REPLY) { + cmd = BR_FAILED_REPLY; + if (put_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + binder_stat_br(proc, thread, cmd); + break; + } + continue; + } + trd->data_size = t->buffer->data_size; + trd->offsets_size = t->buffer->offsets_size; + trd->data.ptr.buffer = (uintptr_t)t->buffer->user_data; + trd->data.ptr.offsets = trd->data.ptr.buffer + + ALIGN(t->buffer->data_size, + sizeof(void *)); + + tr.secctx = t->security_ctx; + if (t->security_ctx) { + cmd = BR_TRANSACTION_SEC_CTX; + trsize = sizeof(tr); + } + if (put_user(cmd, (uint32_t __user *)ptr)) { + if (t_from) + binder_thread_dec_tmpref(t_from); + + binder_cleanup_transaction(t, "put_user failed", + BR_FAILED_REPLY); + + return -EFAULT; + } + ptr += sizeof(uint32_t); + if (copy_to_user(ptr, &tr, trsize)) { + if (t_from) + binder_thread_dec_tmpref(t_from); + + binder_cleanup_transaction(t, "copy_to_user failed", + BR_FAILED_REPLY); + + return -EFAULT; + } + ptr += trsize; + + trace_binder_transaction_received(t); + binder_stat_br(proc, thread, cmd); + binder_debug(BINDER_DEBUG_TRANSACTION, + "%d:%d %s %d %d:%d, cmd %u size %zd-%zd ptr %016llx-%016llx\n", + proc->pid, thread->pid, + (cmd == BR_TRANSACTION) ? "BR_TRANSACTION" : + (cmd == BR_TRANSACTION_SEC_CTX) ? + "BR_TRANSACTION_SEC_CTX" : "BR_REPLY", + t->debug_id, t_from ? t_from->proc->pid : 0, + t_from ? t_from->pid : 0, cmd, + t->buffer->data_size, t->buffer->offsets_size, + (u64)trd->data.ptr.buffer, + (u64)trd->data.ptr.offsets); + + if (t_from) + binder_thread_dec_tmpref(t_from); + t->buffer->allow_user_free = 1; + if (cmd != BR_REPLY && !(t->flags & TF_ONE_WAY)) { + binder_inner_proc_lock(thread->proc); + t->to_parent = thread->transaction_stack; + t->to_thread = thread; + thread->transaction_stack = t; + binder_inner_proc_unlock(thread->proc); + } else { + binder_free_transaction(t); + } + break; + } + +done: + + *consumed = ptr - buffer; + binder_inner_proc_lock(proc); + if (proc->requested_threads == 0 && + list_empty(&thread->proc->waiting_threads) && + proc->requested_threads_started < proc->max_threads && + (thread->looper & (BINDER_LOOPER_STATE_REGISTERED | + BINDER_LOOPER_STATE_ENTERED)) /* the user-space code fails to */ + /*spawn a new thread if we leave this out */) { + proc->requested_threads++; + binder_inner_proc_unlock(proc); + binder_debug(BINDER_DEBUG_THREADS, + "%d:%d BR_SPAWN_LOOPER\n", + proc->pid, thread->pid); + if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer)) + return -EFAULT; + binder_stat_br(proc, thread, BR_SPAWN_LOOPER); + } else + binder_inner_proc_unlock(proc); + return 0; +} + +static void binder_release_work(struct binder_proc *proc, + struct list_head *list) +{ + struct binder_work *w; + enum binder_work_type wtype; + + while (1) { + binder_inner_proc_lock(proc); + w = binder_dequeue_work_head_ilocked(list); + wtype = w ? w->type : 0; + binder_inner_proc_unlock(proc); + if (!w) + return; + + switch (wtype) { + case BINDER_WORK_TRANSACTION: { + struct binder_transaction *t; + + t = container_of(w, struct binder_transaction, work); + + binder_cleanup_transaction(t, "process died.", + BR_DEAD_REPLY); + } break; + case BINDER_WORK_RETURN_ERROR: { + struct binder_error *e = container_of( + w, struct binder_error, work); + + binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, + "undelivered TRANSACTION_ERROR: %u\n", + e->cmd); + } break; + case BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT: + case BINDER_WORK_TRANSACTION_COMPLETE: { + binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, + "undelivered TRANSACTION_COMPLETE\n"); + kfree(w); + binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE); + } break; + case BINDER_WORK_DEAD_BINDER_AND_CLEAR: + case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: { + struct binder_ref_death *death; + + death = container_of(w, struct binder_ref_death, work); + binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, + "undelivered death notification, %016llx\n", + (u64)death->cookie); + kfree(death); + binder_stats_deleted(BINDER_STAT_DEATH); + } break; + case BINDER_WORK_NODE: + break; + default: + pr_err("unexpected work type, %d, not freed\n", + wtype); + break; + } + } + +} + +static struct binder_thread *binder_get_thread_ilocked( + struct binder_proc *proc, struct binder_thread *new_thread) +{ + struct binder_thread *thread = NULL; + struct rb_node *parent = NULL; + struct rb_node **p = &proc->threads.rb_node; + + while (*p) { + parent = *p; + thread = rb_entry(parent, struct binder_thread, rb_node); + + if (current->pid < thread->pid) + p = &(*p)->rb_left; + else if (current->pid > thread->pid) + p = &(*p)->rb_right; + else + return thread; + } + if (!new_thread) + return NULL; + thread = new_thread; + binder_stats_created(BINDER_STAT_THREAD); + thread->proc = proc; + thread->pid = current->pid; + atomic_set(&thread->tmp_ref, 0); + init_waitqueue_head(&thread->wait); + INIT_LIST_HEAD(&thread->todo); + rb_link_node(&thread->rb_node, parent, p); + rb_insert_color(&thread->rb_node, &proc->threads); + thread->looper_need_return = true; + thread->return_error.work.type = BINDER_WORK_RETURN_ERROR; + thread->return_error.cmd = BR_OK; + thread->reply_error.work.type = BINDER_WORK_RETURN_ERROR; + thread->reply_error.cmd = BR_OK; + thread->ee.command = BR_OK; + INIT_LIST_HEAD(&new_thread->waiting_thread_node); + return thread; +} + +static struct binder_thread *binder_get_thread(struct binder_proc *proc) +{ + struct binder_thread *thread; + struct binder_thread *new_thread; + + binder_inner_proc_lock(proc); + thread = binder_get_thread_ilocked(proc, NULL); + binder_inner_proc_unlock(proc); + if (!thread) { + new_thread = kzalloc(sizeof(*thread), GFP_KERNEL); + if (new_thread == NULL) + return NULL; + binder_inner_proc_lock(proc); + thread = binder_get_thread_ilocked(proc, new_thread); + binder_inner_proc_unlock(proc); + if (thread != new_thread) + kfree(new_thread); + } + return thread; +} + +static void binder_free_proc(struct binder_proc *proc) +{ + struct binder_device *device; + + BUG_ON(!list_empty(&proc->todo)); + BUG_ON(!list_empty(&proc->delivered_death)); + if (proc->outstanding_txns) + pr_warn("%s: Unexpected outstanding_txns %d\n", + __func__, proc->outstanding_txns); + device = container_of(proc->context, struct binder_device, context); + if (refcount_dec_and_test(&device->ref)) { + kfree(proc->context->name); + kfree(device); + } + binder_alloc_deferred_release(&proc->alloc); + put_task_struct(proc->tsk); + put_cred(proc->cred); + binder_stats_deleted(BINDER_STAT_PROC); + kfree(proc); +} + +static void binder_free_thread(struct binder_thread *thread) +{ + BUG_ON(!list_empty(&thread->todo)); + binder_stats_deleted(BINDER_STAT_THREAD); + binder_proc_dec_tmpref(thread->proc); + kfree(thread); +} + +static int binder_thread_release(struct binder_proc *proc, + struct binder_thread *thread) +{ + struct binder_transaction *t; + struct binder_transaction *send_reply = NULL; + int active_transactions = 0; + struct binder_transaction *last_t = NULL; + + binder_inner_proc_lock(thread->proc); + /* + * take a ref on the proc so it survives + * after we remove this thread from proc->threads. + * The corresponding dec is when we actually + * free the thread in binder_free_thread() + */ + proc->tmp_ref++; + /* + * take a ref on this thread to ensure it + * survives while we are releasing it + */ + atomic_inc(&thread->tmp_ref); + rb_erase(&thread->rb_node, &proc->threads); + t = thread->transaction_stack; + if (t) { + spin_lock(&t->lock); + if (t->to_thread == thread) + send_reply = t; + } else { + __acquire(&t->lock); + } + thread->is_dead = true; + + while (t) { + last_t = t; + active_transactions++; + binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, + "release %d:%d transaction %d %s, still active\n", + proc->pid, thread->pid, + t->debug_id, + (t->to_thread == thread) ? "in" : "out"); + + if (t->to_thread == thread) { + thread->proc->outstanding_txns--; + t->to_proc = NULL; + t->to_thread = NULL; + if (t->buffer) { + t->buffer->transaction = NULL; + t->buffer = NULL; + } + t = t->to_parent; + } else if (t->from == thread) { + t->from = NULL; + t = t->from_parent; + } else + BUG(); + spin_unlock(&last_t->lock); + if (t) + spin_lock(&t->lock); + else + __acquire(&t->lock); + } + /* annotation for sparse, lock not acquired in last iteration above */ + __release(&t->lock); + + /* + * If this thread used poll, make sure we remove the waitqueue from any + * poll data structures holding it. + */ + if (thread->looper & BINDER_LOOPER_STATE_POLL) + wake_up_pollfree(&thread->wait); + + binder_inner_proc_unlock(thread->proc); + + /* + * This is needed to avoid races between wake_up_pollfree() above and + * someone else removing the last entry from the queue for other reasons + * (e.g. ep_remove_wait_queue() being called due to an epoll file + * descriptor being closed). Such other users hold an RCU read lock, so + * we can be sure they're done after we call synchronize_rcu(). + */ + if (thread->looper & BINDER_LOOPER_STATE_POLL) + synchronize_rcu(); + + if (send_reply) + binder_send_failed_reply(send_reply, BR_DEAD_REPLY); + binder_release_work(proc, &thread->todo); + binder_thread_dec_tmpref(thread); + return active_transactions; +} + +static __poll_t binder_poll(struct file *filp, + struct poll_table_struct *wait) +{ + struct binder_proc *proc = filp->private_data; + struct binder_thread *thread = NULL; + bool wait_for_proc_work; + + thread = binder_get_thread(proc); + if (!thread) + return EPOLLERR; + + binder_inner_proc_lock(thread->proc); + thread->looper |= BINDER_LOOPER_STATE_POLL; + wait_for_proc_work = binder_available_for_proc_work_ilocked(thread); + + binder_inner_proc_unlock(thread->proc); + + poll_wait(filp, &thread->wait, wait); + + if (binder_has_work(thread, wait_for_proc_work)) + return EPOLLIN; + + return 0; +} + +static int binder_ioctl_write_read(struct file *filp, + unsigned int cmd, unsigned long arg, + struct binder_thread *thread) +{ + int ret = 0; + struct binder_proc *proc = filp->private_data; + unsigned int size = _IOC_SIZE(cmd); + void __user *ubuf = (void __user *)arg; + struct binder_write_read bwr; + + if (size != sizeof(struct binder_write_read)) { + ret = -EINVAL; + goto out; + } + if (copy_from_user(&bwr, ubuf, sizeof(bwr))) { + ret = -EFAULT; + goto out; + } + binder_debug(BINDER_DEBUG_READ_WRITE, + "%d:%d write %lld at %016llx, read %lld at %016llx\n", + proc->pid, thread->pid, + (u64)bwr.write_size, (u64)bwr.write_buffer, + (u64)bwr.read_size, (u64)bwr.read_buffer); + + if (bwr.write_size > 0) { + ret = binder_thread_write(proc, thread, + bwr.write_buffer, + bwr.write_size, + &bwr.write_consumed); + trace_binder_write_done(ret); + if (ret < 0) { + bwr.read_consumed = 0; + if (copy_to_user(ubuf, &bwr, sizeof(bwr))) + ret = -EFAULT; + goto out; + } + } + if (bwr.read_size > 0) { + ret = binder_thread_read(proc, thread, bwr.read_buffer, + bwr.read_size, + &bwr.read_consumed, + filp->f_flags & O_NONBLOCK); + trace_binder_read_done(ret); + binder_inner_proc_lock(proc); + if (!binder_worklist_empty_ilocked(&proc->todo)) + binder_wakeup_proc_ilocked(proc); + binder_inner_proc_unlock(proc); + if (ret < 0) { + if (copy_to_user(ubuf, &bwr, sizeof(bwr))) + ret = -EFAULT; + goto out; + } + } + binder_debug(BINDER_DEBUG_READ_WRITE, + "%d:%d wrote %lld of %lld, read return %lld of %lld\n", + proc->pid, thread->pid, + (u64)bwr.write_consumed, (u64)bwr.write_size, + (u64)bwr.read_consumed, (u64)bwr.read_size); + if (copy_to_user(ubuf, &bwr, sizeof(bwr))) { + ret = -EFAULT; + goto out; + } +out: + return ret; +} + +static int binder_ioctl_set_ctx_mgr(struct file *filp, + struct flat_binder_object *fbo) +{ + int ret = 0; + struct binder_proc *proc = filp->private_data; + struct binder_context *context = proc->context; + struct binder_node *new_node; + kuid_t curr_euid = current_euid(); + + mutex_lock(&context->context_mgr_node_lock); + if (context->binder_context_mgr_node) { + pr_err("BINDER_SET_CONTEXT_MGR already set\n"); + ret = -EBUSY; + goto out; + } + ret = security_binder_set_context_mgr(proc->cred); + if (ret < 0) + goto out; + if (uid_valid(context->binder_context_mgr_uid)) { + if (!uid_eq(context->binder_context_mgr_uid, curr_euid)) { + pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n", + from_kuid(&init_user_ns, curr_euid), + from_kuid(&init_user_ns, + context->binder_context_mgr_uid)); + ret = -EPERM; + goto out; + } + } else { + context->binder_context_mgr_uid = curr_euid; + } + new_node = binder_new_node(proc, fbo); + if (!new_node) { + ret = -ENOMEM; + goto out; + } + binder_node_lock(new_node); + new_node->local_weak_refs++; + new_node->local_strong_refs++; + new_node->has_strong_ref = 1; + new_node->has_weak_ref = 1; + context->binder_context_mgr_node = new_node; + binder_node_unlock(new_node); + binder_put_node(new_node); +out: + mutex_unlock(&context->context_mgr_node_lock); + return ret; +} + +static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc, + struct binder_node_info_for_ref *info) +{ + struct binder_node *node; + struct binder_context *context = proc->context; + __u32 handle = info->handle; + + if (info->strong_count || info->weak_count || info->reserved1 || + info->reserved2 || info->reserved3) { + binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.", + proc->pid); + return -EINVAL; + } + + /* This ioctl may only be used by the context manager */ + mutex_lock(&context->context_mgr_node_lock); + if (!context->binder_context_mgr_node || + context->binder_context_mgr_node->proc != proc) { + mutex_unlock(&context->context_mgr_node_lock); + return -EPERM; + } + mutex_unlock(&context->context_mgr_node_lock); + + node = binder_get_node_from_ref(proc, handle, true, NULL); + if (!node) + return -EINVAL; + + info->strong_count = node->local_strong_refs + + node->internal_strong_refs; + info->weak_count = node->local_weak_refs; + + binder_put_node(node); + + return 0; +} + +static int binder_ioctl_get_node_debug_info(struct binder_proc *proc, + struct binder_node_debug_info *info) +{ + struct rb_node *n; + binder_uintptr_t ptr = info->ptr; + + memset(info, 0, sizeof(*info)); + + binder_inner_proc_lock(proc); + for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) { + struct binder_node *node = rb_entry(n, struct binder_node, + rb_node); + if (node->ptr > ptr) { + info->ptr = node->ptr; + info->cookie = node->cookie; + info->has_strong_ref = node->has_strong_ref; + info->has_weak_ref = node->has_weak_ref; + break; + } + } + binder_inner_proc_unlock(proc); + + return 0; +} + +static bool binder_txns_pending_ilocked(struct binder_proc *proc) +{ + struct rb_node *n; + struct binder_thread *thread; + + if (proc->outstanding_txns > 0) + return true; + + for (n = rb_first(&proc->threads); n; n = rb_next(n)) { + thread = rb_entry(n, struct binder_thread, rb_node); + if (thread->transaction_stack) + return true; + } + return false; +} + +static int binder_ioctl_freeze(struct binder_freeze_info *info, + struct binder_proc *target_proc) +{ + int ret = 0; + + if (!info->enable) { + binder_inner_proc_lock(target_proc); + target_proc->sync_recv = false; + target_proc->async_recv = false; + target_proc->is_frozen = false; + binder_inner_proc_unlock(target_proc); + return 0; + } + + /* + * Freezing the target. Prevent new transactions by + * setting frozen state. If timeout specified, wait + * for transactions to drain. + */ + binder_inner_proc_lock(target_proc); + target_proc->sync_recv = false; + target_proc->async_recv = false; + target_proc->is_frozen = true; + binder_inner_proc_unlock(target_proc); + + if (info->timeout_ms > 0) + ret = wait_event_interruptible_timeout( + target_proc->freeze_wait, + (!target_proc->outstanding_txns), + msecs_to_jiffies(info->timeout_ms)); + + /* Check pending transactions that wait for reply */ + if (ret >= 0) { + binder_inner_proc_lock(target_proc); + if (binder_txns_pending_ilocked(target_proc)) + ret = -EAGAIN; + binder_inner_proc_unlock(target_proc); + } + + if (ret < 0) { + binder_inner_proc_lock(target_proc); + target_proc->is_frozen = false; + binder_inner_proc_unlock(target_proc); + } + + return ret; +} + +static int binder_ioctl_get_freezer_info( + struct binder_frozen_status_info *info) +{ + struct binder_proc *target_proc; + bool found = false; + __u32 txns_pending; + + info->sync_recv = 0; + info->async_recv = 0; + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(target_proc, &binder_procs, proc_node) { + if (target_proc->pid == info->pid) { + found = true; + binder_inner_proc_lock(target_proc); + txns_pending = binder_txns_pending_ilocked(target_proc); + info->sync_recv |= target_proc->sync_recv | + (txns_pending << 1); + info->async_recv |= target_proc->async_recv; + binder_inner_proc_unlock(target_proc); + } + } + mutex_unlock(&binder_procs_lock); + + if (!found) + return -EINVAL; + + return 0; +} + +static int binder_ioctl_get_extended_error(struct binder_thread *thread, + void __user *ubuf) +{ + struct binder_extended_error ee; + + binder_inner_proc_lock(thread->proc); + ee = thread->ee; + binder_set_extended_error(&thread->ee, 0, BR_OK, 0); + binder_inner_proc_unlock(thread->proc); + + if (copy_to_user(ubuf, &ee, sizeof(ee))) + return -EFAULT; + + return 0; +} + +static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) +{ + int ret; + struct binder_proc *proc = filp->private_data; + struct binder_thread *thread; + unsigned int size = _IOC_SIZE(cmd); + void __user *ubuf = (void __user *)arg; + + /*pr_info("binder_ioctl: %d:%d %x %lx\n", + proc->pid, current->pid, cmd, arg);*/ + + binder_selftest_alloc(&proc->alloc); + + trace_binder_ioctl(cmd, arg); + + ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2); + if (ret) + goto err_unlocked; + + thread = binder_get_thread(proc); + if (thread == NULL) { + ret = -ENOMEM; + goto err; + } + + switch (cmd) { + case BINDER_WRITE_READ: + ret = binder_ioctl_write_read(filp, cmd, arg, thread); + if (ret) + goto err; + break; + case BINDER_SET_MAX_THREADS: { + int max_threads; + + if (copy_from_user(&max_threads, ubuf, + sizeof(max_threads))) { + ret = -EINVAL; + goto err; + } + binder_inner_proc_lock(proc); + proc->max_threads = max_threads; + binder_inner_proc_unlock(proc); + break; + } + case BINDER_SET_CONTEXT_MGR_EXT: { + struct flat_binder_object fbo; + + if (copy_from_user(&fbo, ubuf, sizeof(fbo))) { + ret = -EINVAL; + goto err; + } + ret = binder_ioctl_set_ctx_mgr(filp, &fbo); + if (ret) + goto err; + break; + } + case BINDER_SET_CONTEXT_MGR: + ret = binder_ioctl_set_ctx_mgr(filp, NULL); + if (ret) + goto err; + break; + case BINDER_THREAD_EXIT: + binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n", + proc->pid, thread->pid); + binder_thread_release(proc, thread); + thread = NULL; + break; + case BINDER_VERSION: { + struct binder_version __user *ver = ubuf; + + if (size != sizeof(struct binder_version)) { + ret = -EINVAL; + goto err; + } + if (put_user(BINDER_CURRENT_PROTOCOL_VERSION, + &ver->protocol_version)) { + ret = -EINVAL; + goto err; + } + break; + } + case BINDER_GET_NODE_INFO_FOR_REF: { + struct binder_node_info_for_ref info; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + ret = binder_ioctl_get_node_info_for_ref(proc, &info); + if (ret < 0) + goto err; + + if (copy_to_user(ubuf, &info, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + break; + } + case BINDER_GET_NODE_DEBUG_INFO: { + struct binder_node_debug_info info; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + ret = binder_ioctl_get_node_debug_info(proc, &info); + if (ret < 0) + goto err; + + if (copy_to_user(ubuf, &info, sizeof(info))) { + ret = -EFAULT; + goto err; + } + break; + } + case BINDER_FREEZE: { + struct binder_freeze_info info; + struct binder_proc **target_procs = NULL, *target_proc; + int target_procs_count = 0, i = 0; + + ret = 0; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(target_proc, &binder_procs, proc_node) { + if (target_proc->pid == info.pid) + target_procs_count++; + } + + if (target_procs_count == 0) { + mutex_unlock(&binder_procs_lock); + ret = -EINVAL; + goto err; + } + + target_procs = kcalloc(target_procs_count, + sizeof(struct binder_proc *), + GFP_KERNEL); + + if (!target_procs) { + mutex_unlock(&binder_procs_lock); + ret = -ENOMEM; + goto err; + } + + hlist_for_each_entry(target_proc, &binder_procs, proc_node) { + if (target_proc->pid != info.pid) + continue; + + binder_inner_proc_lock(target_proc); + target_proc->tmp_ref++; + binder_inner_proc_unlock(target_proc); + + target_procs[i++] = target_proc; + } + mutex_unlock(&binder_procs_lock); + + for (i = 0; i < target_procs_count; i++) { + if (ret >= 0) + ret = binder_ioctl_freeze(&info, + target_procs[i]); + + binder_proc_dec_tmpref(target_procs[i]); + } + + kfree(target_procs); + + if (ret < 0) + goto err; + break; + } + case BINDER_GET_FROZEN_INFO: { + struct binder_frozen_status_info info; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + ret = binder_ioctl_get_freezer_info(&info); + if (ret < 0) + goto err; + + if (copy_to_user(ubuf, &info, sizeof(info))) { + ret = -EFAULT; + goto err; + } + break; + } + case BINDER_ENABLE_ONEWAY_SPAM_DETECTION: { + uint32_t enable; + + if (copy_from_user(&enable, ubuf, sizeof(enable))) { + ret = -EFAULT; + goto err; + } + binder_inner_proc_lock(proc); + proc->oneway_spam_detection_enabled = (bool)enable; + binder_inner_proc_unlock(proc); + break; + } + case BINDER_GET_EXTENDED_ERROR: + ret = binder_ioctl_get_extended_error(thread, ubuf); + if (ret < 0) + goto err; + break; + default: + ret = -EINVAL; + goto err; + } + ret = 0; +err: + if (thread) + thread->looper_need_return = false; + wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2); + if (ret && ret != -EINTR) + pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret); +err_unlocked: + trace_binder_ioctl_done(ret); + return ret; +} + +static void binder_vma_open(struct vm_area_struct *vma) +{ + struct binder_proc *proc = vma->vm_private_data; + + binder_debug(BINDER_DEBUG_OPEN_CLOSE, + "%d open vm area %lx-%lx (%ld K) vma %lx pagep %lx\n", + proc->pid, vma->vm_start, vma->vm_end, + (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags, + (unsigned long)pgprot_val(vma->vm_page_prot)); +} + +static void binder_vma_close(struct vm_area_struct *vma) +{ + struct binder_proc *proc = vma->vm_private_data; + + binder_debug(BINDER_DEBUG_OPEN_CLOSE, + "%d close vm area %lx-%lx (%ld K) vma %lx pagep %lx\n", + proc->pid, vma->vm_start, vma->vm_end, + (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags, + (unsigned long)pgprot_val(vma->vm_page_prot)); + binder_alloc_vma_close(&proc->alloc); +} + +static vm_fault_t binder_vm_fault(struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + +static const struct vm_operations_struct binder_vm_ops = { + .open = binder_vma_open, + .close = binder_vma_close, + .fault = binder_vm_fault, +}; + +static int binder_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct binder_proc *proc = filp->private_data; + + if (proc->tsk != current->group_leader) + return -EINVAL; + + binder_debug(BINDER_DEBUG_OPEN_CLOSE, + "%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n", + __func__, proc->pid, vma->vm_start, vma->vm_end, + (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags, + (unsigned long)pgprot_val(vma->vm_page_prot)); + + if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) { + pr_err("%s: %d %lx-%lx %s failed %d\n", __func__, + proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM); + return -EPERM; + } + vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP; + vma->vm_flags &= ~VM_MAYWRITE; + + vma->vm_ops = &binder_vm_ops; + vma->vm_private_data = proc; + + return binder_alloc_mmap_handler(&proc->alloc, vma); +} + +static int binder_open(struct inode *nodp, struct file *filp) +{ + struct binder_proc *proc, *itr; + struct binder_device *binder_dev; + struct binderfs_info *info; + struct dentry *binder_binderfs_dir_entry_proc = NULL; + bool existing_pid = false; + + binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__, + current->group_leader->pid, current->pid); + + proc = kzalloc(sizeof(*proc), GFP_KERNEL); + if (proc == NULL) + return -ENOMEM; + spin_lock_init(&proc->inner_lock); + spin_lock_init(&proc->outer_lock); + get_task_struct(current->group_leader); + proc->tsk = current->group_leader; + proc->cred = get_cred(filp->f_cred); + INIT_LIST_HEAD(&proc->todo); + init_waitqueue_head(&proc->freeze_wait); + proc->default_priority = task_nice(current); + /* binderfs stashes devices in i_private */ + if (is_binderfs_device(nodp)) { + binder_dev = nodp->i_private; + info = nodp->i_sb->s_fs_info; + binder_binderfs_dir_entry_proc = info->proc_log_dir; + } else { + binder_dev = container_of(filp->private_data, + struct binder_device, miscdev); + } + refcount_inc(&binder_dev->ref); + proc->context = &binder_dev->context; + binder_alloc_init(&proc->alloc); + + binder_stats_created(BINDER_STAT_PROC); + proc->pid = current->group_leader->pid; + INIT_LIST_HEAD(&proc->delivered_death); + INIT_LIST_HEAD(&proc->waiting_threads); + filp->private_data = proc; + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(itr, &binder_procs, proc_node) { + if (itr->pid == proc->pid) { + existing_pid = true; + break; + } + } + hlist_add_head(&proc->proc_node, &binder_procs); + mutex_unlock(&binder_procs_lock); + + if (binder_debugfs_dir_entry_proc && !existing_pid) { + char strbuf[11]; + + snprintf(strbuf, sizeof(strbuf), "%u", proc->pid); + /* + * proc debug entries are shared between contexts. + * Only create for the first PID to avoid debugfs log spamming + * The printing code will anyway print all contexts for a given + * PID so this is not a problem. + */ + proc->debugfs_entry = debugfs_create_file(strbuf, 0444, + binder_debugfs_dir_entry_proc, + (void *)(unsigned long)proc->pid, + &proc_fops); + } + + if (binder_binderfs_dir_entry_proc && !existing_pid) { + char strbuf[11]; + struct dentry *binderfs_entry; + + snprintf(strbuf, sizeof(strbuf), "%u", proc->pid); + /* + * Similar to debugfs, the process specific log file is shared + * between contexts. Only create for the first PID. + * This is ok since same as debugfs, the log file will contain + * information on all contexts of a given PID. + */ + binderfs_entry = binderfs_create_file(binder_binderfs_dir_entry_proc, + strbuf, &proc_fops, (void *)(unsigned long)proc->pid); + if (!IS_ERR(binderfs_entry)) { + proc->binderfs_entry = binderfs_entry; + } else { + int error; + + error = PTR_ERR(binderfs_entry); + pr_warn("Unable to create file %s in binderfs (error %d)\n", + strbuf, error); + } + } + + return 0; +} + +static int binder_flush(struct file *filp, fl_owner_t id) +{ + struct binder_proc *proc = filp->private_data; + + binder_defer_work(proc, BINDER_DEFERRED_FLUSH); + + return 0; +} + +static void binder_deferred_flush(struct binder_proc *proc) +{ + struct rb_node *n; + int wake_count = 0; + + binder_inner_proc_lock(proc); + for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) { + struct binder_thread *thread = rb_entry(n, struct binder_thread, rb_node); + + thread->looper_need_return = true; + if (thread->looper & BINDER_LOOPER_STATE_WAITING) { + wake_up_interruptible(&thread->wait); + wake_count++; + } + } + binder_inner_proc_unlock(proc); + + binder_debug(BINDER_DEBUG_OPEN_CLOSE, + "binder_flush: %d woke %d threads\n", proc->pid, + wake_count); +} + +static int binder_release(struct inode *nodp, struct file *filp) +{ + struct binder_proc *proc = filp->private_data; + + debugfs_remove(proc->debugfs_entry); + + if (proc->binderfs_entry) { + binderfs_remove_file(proc->binderfs_entry); + proc->binderfs_entry = NULL; + } + + binder_defer_work(proc, BINDER_DEFERRED_RELEASE); + + return 0; +} + +static int binder_node_release(struct binder_node *node, int refs) +{ + struct binder_ref *ref; + int death = 0; + struct binder_proc *proc = node->proc; + + binder_release_work(proc, &node->async_todo); + + binder_node_lock(node); + binder_inner_proc_lock(proc); + binder_dequeue_work_ilocked(&node->work); + /* + * The caller must have taken a temporary ref on the node, + */ + BUG_ON(!node->tmp_refs); + if (hlist_empty(&node->refs) && node->tmp_refs == 1) { + binder_inner_proc_unlock(proc); + binder_node_unlock(node); + binder_free_node(node); + + return refs; + } + + node->proc = NULL; + node->local_strong_refs = 0; + node->local_weak_refs = 0; + binder_inner_proc_unlock(proc); + + spin_lock(&binder_dead_nodes_lock); + hlist_add_head(&node->dead_node, &binder_dead_nodes); + spin_unlock(&binder_dead_nodes_lock); + + hlist_for_each_entry(ref, &node->refs, node_entry) { + refs++; + /* + * Need the node lock to synchronize + * with new notification requests and the + * inner lock to synchronize with queued + * death notifications. + */ + binder_inner_proc_lock(ref->proc); + if (!ref->death) { + binder_inner_proc_unlock(ref->proc); + continue; + } + + death++; + + BUG_ON(!list_empty(&ref->death->work.entry)); + ref->death->work.type = BINDER_WORK_DEAD_BINDER; + binder_enqueue_work_ilocked(&ref->death->work, + &ref->proc->todo); + binder_wakeup_proc_ilocked(ref->proc); + binder_inner_proc_unlock(ref->proc); + } + + binder_debug(BINDER_DEBUG_DEAD_BINDER, + "node %d now dead, refs %d, death %d\n", + node->debug_id, refs, death); + binder_node_unlock(node); + binder_put_node(node); + + return refs; +} + +static void binder_deferred_release(struct binder_proc *proc) +{ + struct binder_context *context = proc->context; + struct rb_node *n; + int threads, nodes, incoming_refs, outgoing_refs, active_transactions; + + mutex_lock(&binder_procs_lock); + hlist_del(&proc->proc_node); + mutex_unlock(&binder_procs_lock); + + mutex_lock(&context->context_mgr_node_lock); + if (context->binder_context_mgr_node && + context->binder_context_mgr_node->proc == proc) { + binder_debug(BINDER_DEBUG_DEAD_BINDER, + "%s: %d context_mgr_node gone\n", + __func__, proc->pid); + context->binder_context_mgr_node = NULL; + } + mutex_unlock(&context->context_mgr_node_lock); + binder_inner_proc_lock(proc); + /* + * Make sure proc stays alive after we + * remove all the threads + */ + proc->tmp_ref++; + + proc->is_dead = true; + proc->is_frozen = false; + proc->sync_recv = false; + proc->async_recv = false; + threads = 0; + active_transactions = 0; + while ((n = rb_first(&proc->threads))) { + struct binder_thread *thread; + + thread = rb_entry(n, struct binder_thread, rb_node); + binder_inner_proc_unlock(proc); + threads++; + active_transactions += binder_thread_release(proc, thread); + binder_inner_proc_lock(proc); + } + + nodes = 0; + incoming_refs = 0; + while ((n = rb_first(&proc->nodes))) { + struct binder_node *node; + + node = rb_entry(n, struct binder_node, rb_node); + nodes++; + /* + * take a temporary ref on the node before + * calling binder_node_release() which will either + * kfree() the node or call binder_put_node() + */ + binder_inc_node_tmpref_ilocked(node); + rb_erase(&node->rb_node, &proc->nodes); + binder_inner_proc_unlock(proc); + incoming_refs = binder_node_release(node, incoming_refs); + binder_inner_proc_lock(proc); + } + binder_inner_proc_unlock(proc); + + outgoing_refs = 0; + binder_proc_lock(proc); + while ((n = rb_first(&proc->refs_by_desc))) { + struct binder_ref *ref; + + ref = rb_entry(n, struct binder_ref, rb_node_desc); + outgoing_refs++; + binder_cleanup_ref_olocked(ref); + binder_proc_unlock(proc); + binder_free_ref(ref); + binder_proc_lock(proc); + } + binder_proc_unlock(proc); + + binder_release_work(proc, &proc->todo); + binder_release_work(proc, &proc->delivered_death); + + binder_debug(BINDER_DEBUG_OPEN_CLOSE, + "%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d\n", + __func__, proc->pid, threads, nodes, incoming_refs, + outgoing_refs, active_transactions); + + binder_proc_dec_tmpref(proc); +} + +static void binder_deferred_func(struct work_struct *work) +{ + struct binder_proc *proc; + + int defer; + + do { + mutex_lock(&binder_deferred_lock); + if (!hlist_empty(&binder_deferred_list)) { + proc = hlist_entry(binder_deferred_list.first, + struct binder_proc, deferred_work_node); + hlist_del_init(&proc->deferred_work_node); + defer = proc->deferred_work; + proc->deferred_work = 0; + } else { + proc = NULL; + defer = 0; + } + mutex_unlock(&binder_deferred_lock); + + if (defer & BINDER_DEFERRED_FLUSH) + binder_deferred_flush(proc); + + if (defer & BINDER_DEFERRED_RELEASE) + binder_deferred_release(proc); /* frees proc */ + } while (proc); +} +static DECLARE_WORK(binder_deferred_work, binder_deferred_func); + +static void +binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer) +{ + mutex_lock(&binder_deferred_lock); + proc->deferred_work |= defer; + if (hlist_unhashed(&proc->deferred_work_node)) { + hlist_add_head(&proc->deferred_work_node, + &binder_deferred_list); + schedule_work(&binder_deferred_work); + } + mutex_unlock(&binder_deferred_lock); +} + +static void print_binder_transaction_ilocked(struct seq_file *m, + struct binder_proc *proc, + const char *prefix, + struct binder_transaction *t) +{ + struct binder_proc *to_proc; + struct binder_buffer *buffer = t->buffer; + + spin_lock(&t->lock); + to_proc = t->to_proc; + seq_printf(m, + "%s %d: %pK from %d:%d to %d:%d code %x flags %x pri %ld r%d", + prefix, t->debug_id, t, + t->from ? t->from->proc->pid : 0, + t->from ? t->from->pid : 0, + to_proc ? to_proc->pid : 0, + t->to_thread ? t->to_thread->pid : 0, + t->code, t->flags, t->priority, t->need_reply); + spin_unlock(&t->lock); + + if (proc != to_proc) { + /* + * Can only safely deref buffer if we are holding the + * correct proc inner lock for this node + */ + seq_puts(m, "\n"); + return; + } + + if (buffer == NULL) { + seq_puts(m, " buffer free\n"); + return; + } + if (buffer->target_node) + seq_printf(m, " node %d", buffer->target_node->debug_id); + seq_printf(m, " size %zd:%zd data %pK\n", + buffer->data_size, buffer->offsets_size, + buffer->user_data); +} + +static void print_binder_work_ilocked(struct seq_file *m, + struct binder_proc *proc, + const char *prefix, + const char *transaction_prefix, + struct binder_work *w) +{ + struct binder_node *node; + struct binder_transaction *t; + + switch (w->type) { + case BINDER_WORK_TRANSACTION: + t = container_of(w, struct binder_transaction, work); + print_binder_transaction_ilocked( + m, proc, transaction_prefix, t); + break; + case BINDER_WORK_RETURN_ERROR: { + struct binder_error *e = container_of( + w, struct binder_error, work); + + seq_printf(m, "%stransaction error: %u\n", + prefix, e->cmd); + } break; + case BINDER_WORK_TRANSACTION_COMPLETE: + seq_printf(m, "%stransaction complete\n", prefix); + break; + case BINDER_WORK_NODE: + node = container_of(w, struct binder_node, work); + seq_printf(m, "%snode work %d: u%016llx c%016llx\n", + prefix, node->debug_id, + (u64)node->ptr, (u64)node->cookie); + break; + case BINDER_WORK_DEAD_BINDER: + seq_printf(m, "%shas dead binder\n", prefix); + break; + case BINDER_WORK_DEAD_BINDER_AND_CLEAR: + seq_printf(m, "%shas cleared dead binder\n", prefix); + break; + case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: + seq_printf(m, "%shas cleared death notification\n", prefix); + break; + default: + seq_printf(m, "%sunknown work: type %d\n", prefix, w->type); + break; + } +} + +static void print_binder_thread_ilocked(struct seq_file *m, + struct binder_thread *thread, + int print_always) +{ + struct binder_transaction *t; + struct binder_work *w; + size_t start_pos = m->count; + size_t header_pos; + + seq_printf(m, " thread %d: l %02x need_return %d tr %d\n", + thread->pid, thread->looper, + thread->looper_need_return, + atomic_read(&thread->tmp_ref)); + header_pos = m->count; + t = thread->transaction_stack; + while (t) { + if (t->from == thread) { + print_binder_transaction_ilocked(m, thread->proc, + " outgoing transaction", t); + t = t->from_parent; + } else if (t->to_thread == thread) { + print_binder_transaction_ilocked(m, thread->proc, + " incoming transaction", t); + t = t->to_parent; + } else { + print_binder_transaction_ilocked(m, thread->proc, + " bad transaction", t); + t = NULL; + } + } + list_for_each_entry(w, &thread->todo, entry) { + print_binder_work_ilocked(m, thread->proc, " ", + " pending transaction", w); + } + if (!print_always && m->count == header_pos) + m->count = start_pos; +} + +static void print_binder_node_nilocked(struct seq_file *m, + struct binder_node *node) +{ + struct binder_ref *ref; + struct binder_work *w; + int count; + + count = 0; + hlist_for_each_entry(ref, &node->refs, node_entry) + count++; + + seq_printf(m, " node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d tr %d", + node->debug_id, (u64)node->ptr, (u64)node->cookie, + node->has_strong_ref, node->has_weak_ref, + node->local_strong_refs, node->local_weak_refs, + node->internal_strong_refs, count, node->tmp_refs); + if (count) { + seq_puts(m, " proc"); + hlist_for_each_entry(ref, &node->refs, node_entry) + seq_printf(m, " %d", ref->proc->pid); + } + seq_puts(m, "\n"); + if (node->proc) { + list_for_each_entry(w, &node->async_todo, entry) + print_binder_work_ilocked(m, node->proc, " ", + " pending async transaction", w); + } +} + +static void print_binder_ref_olocked(struct seq_file *m, + struct binder_ref *ref) +{ + binder_node_lock(ref->node); + seq_printf(m, " ref %d: desc %d %snode %d s %d w %d d %pK\n", + ref->data.debug_id, ref->data.desc, + ref->node->proc ? "" : "dead ", + ref->node->debug_id, ref->data.strong, + ref->data.weak, ref->death); + binder_node_unlock(ref->node); +} + +static void print_binder_proc(struct seq_file *m, + struct binder_proc *proc, int print_all) +{ + struct binder_work *w; + struct rb_node *n; + size_t start_pos = m->count; + size_t header_pos; + struct binder_node *last_node = NULL; + + seq_printf(m, "proc %d\n", proc->pid); + seq_printf(m, "context %s\n", proc->context->name); + header_pos = m->count; + + binder_inner_proc_lock(proc); + for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) + print_binder_thread_ilocked(m, rb_entry(n, struct binder_thread, + rb_node), print_all); + + for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) { + struct binder_node *node = rb_entry(n, struct binder_node, + rb_node); + if (!print_all && !node->has_async_transaction) + continue; + + /* + * take a temporary reference on the node so it + * survives and isn't removed from the tree + * while we print it. + */ + binder_inc_node_tmpref_ilocked(node); + /* Need to drop inner lock to take node lock */ + binder_inner_proc_unlock(proc); + if (last_node) + binder_put_node(last_node); + binder_node_inner_lock(node); + print_binder_node_nilocked(m, node); + binder_node_inner_unlock(node); + last_node = node; + binder_inner_proc_lock(proc); + } + binder_inner_proc_unlock(proc); + if (last_node) + binder_put_node(last_node); + + if (print_all) { + binder_proc_lock(proc); + for (n = rb_first(&proc->refs_by_desc); + n != NULL; + n = rb_next(n)) + print_binder_ref_olocked(m, rb_entry(n, + struct binder_ref, + rb_node_desc)); + binder_proc_unlock(proc); + } + binder_alloc_print_allocated(m, &proc->alloc); + binder_inner_proc_lock(proc); + list_for_each_entry(w, &proc->todo, entry) + print_binder_work_ilocked(m, proc, " ", + " pending transaction", w); + list_for_each_entry(w, &proc->delivered_death, entry) { + seq_puts(m, " has delivered dead binder\n"); + break; + } + binder_inner_proc_unlock(proc); + if (!print_all && m->count == header_pos) + m->count = start_pos; +} + +static const char * const binder_return_strings[] = { + "BR_ERROR", + "BR_OK", + "BR_TRANSACTION", + "BR_REPLY", + "BR_ACQUIRE_RESULT", + "BR_DEAD_REPLY", + "BR_TRANSACTION_COMPLETE", + "BR_INCREFS", + "BR_ACQUIRE", + "BR_RELEASE", + "BR_DECREFS", + "BR_ATTEMPT_ACQUIRE", + "BR_NOOP", + "BR_SPAWN_LOOPER", + "BR_FINISHED", + "BR_DEAD_BINDER", + "BR_CLEAR_DEATH_NOTIFICATION_DONE", + "BR_FAILED_REPLY", + "BR_FROZEN_REPLY", + "BR_ONEWAY_SPAM_SUSPECT", +}; + +static const char * const binder_command_strings[] = { + "BC_TRANSACTION", + "BC_REPLY", + "BC_ACQUIRE_RESULT", + "BC_FREE_BUFFER", + "BC_INCREFS", + "BC_ACQUIRE", + "BC_RELEASE", + "BC_DECREFS", + "BC_INCREFS_DONE", + "BC_ACQUIRE_DONE", + "BC_ATTEMPT_ACQUIRE", + "BC_REGISTER_LOOPER", + "BC_ENTER_LOOPER", + "BC_EXIT_LOOPER", + "BC_REQUEST_DEATH_NOTIFICATION", + "BC_CLEAR_DEATH_NOTIFICATION", + "BC_DEAD_BINDER_DONE", + "BC_TRANSACTION_SG", + "BC_REPLY_SG", +}; + +static const char * const binder_objstat_strings[] = { + "proc", + "thread", + "node", + "ref", + "death", + "transaction", + "transaction_complete" +}; + +static void print_binder_stats(struct seq_file *m, const char *prefix, + struct binder_stats *stats) +{ + int i; + + BUILD_BUG_ON(ARRAY_SIZE(stats->bc) != + ARRAY_SIZE(binder_command_strings)); + for (i = 0; i < ARRAY_SIZE(stats->bc); i++) { + int temp = atomic_read(&stats->bc[i]); + + if (temp) + seq_printf(m, "%s%s: %d\n", prefix, + binder_command_strings[i], temp); + } + + BUILD_BUG_ON(ARRAY_SIZE(stats->br) != + ARRAY_SIZE(binder_return_strings)); + for (i = 0; i < ARRAY_SIZE(stats->br); i++) { + int temp = atomic_read(&stats->br[i]); + + if (temp) + seq_printf(m, "%s%s: %d\n", prefix, + binder_return_strings[i], temp); + } + + BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) != + ARRAY_SIZE(binder_objstat_strings)); + BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) != + ARRAY_SIZE(stats->obj_deleted)); + for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) { + int created = atomic_read(&stats->obj_created[i]); + int deleted = atomic_read(&stats->obj_deleted[i]); + + if (created || deleted) + seq_printf(m, "%s%s: active %d total %d\n", + prefix, + binder_objstat_strings[i], + created - deleted, + created); + } +} + +static void print_binder_proc_stats(struct seq_file *m, + struct binder_proc *proc) +{ + struct binder_work *w; + struct binder_thread *thread; + struct rb_node *n; + int count, strong, weak, ready_threads; + size_t free_async_space = + binder_alloc_get_free_async_space(&proc->alloc); + + seq_printf(m, "proc %d\n", proc->pid); + seq_printf(m, "context %s\n", proc->context->name); + count = 0; + ready_threads = 0; + binder_inner_proc_lock(proc); + for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) + count++; + + list_for_each_entry(thread, &proc->waiting_threads, waiting_thread_node) + ready_threads++; + + seq_printf(m, " threads: %d\n", count); + seq_printf(m, " requested threads: %d+%d/%d\n" + " ready threads %d\n" + " free async space %zd\n", proc->requested_threads, + proc->requested_threads_started, proc->max_threads, + ready_threads, + free_async_space); + count = 0; + for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) + count++; + binder_inner_proc_unlock(proc); + seq_printf(m, " nodes: %d\n", count); + count = 0; + strong = 0; + weak = 0; + binder_proc_lock(proc); + for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) { + struct binder_ref *ref = rb_entry(n, struct binder_ref, + rb_node_desc); + count++; + strong += ref->data.strong; + weak += ref->data.weak; + } + binder_proc_unlock(proc); + seq_printf(m, " refs: %d s %d w %d\n", count, strong, weak); + + count = binder_alloc_get_allocated_count(&proc->alloc); + seq_printf(m, " buffers: %d\n", count); + + binder_alloc_print_pages(m, &proc->alloc); + + count = 0; + binder_inner_proc_lock(proc); + list_for_each_entry(w, &proc->todo, entry) { + if (w->type == BINDER_WORK_TRANSACTION) + count++; + } + binder_inner_proc_unlock(proc); + seq_printf(m, " pending transactions: %d\n", count); + + print_binder_stats(m, " ", &proc->stats); +} + +static int state_show(struct seq_file *m, void *unused) +{ + struct binder_proc *proc; + struct binder_node *node; + struct binder_node *last_node = NULL; + + seq_puts(m, "binder state:\n"); + + spin_lock(&binder_dead_nodes_lock); + if (!hlist_empty(&binder_dead_nodes)) + seq_puts(m, "dead nodes:\n"); + hlist_for_each_entry(node, &binder_dead_nodes, dead_node) { + /* + * take a temporary reference on the node so it + * survives and isn't removed from the list + * while we print it. + */ + node->tmp_refs++; + spin_unlock(&binder_dead_nodes_lock); + if (last_node) + binder_put_node(last_node); + binder_node_lock(node); + print_binder_node_nilocked(m, node); + binder_node_unlock(node); + last_node = node; + spin_lock(&binder_dead_nodes_lock); + } + spin_unlock(&binder_dead_nodes_lock); + if (last_node) + binder_put_node(last_node); + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(proc, &binder_procs, proc_node) + print_binder_proc(m, proc, 1); + mutex_unlock(&binder_procs_lock); + + return 0; +} + +static int stats_show(struct seq_file *m, void *unused) +{ + struct binder_proc *proc; + + seq_puts(m, "binder stats:\n"); + + print_binder_stats(m, "", &binder_stats); + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(proc, &binder_procs, proc_node) + print_binder_proc_stats(m, proc); + mutex_unlock(&binder_procs_lock); + + return 0; +} + +static int transactions_show(struct seq_file *m, void *unused) +{ + struct binder_proc *proc; + + seq_puts(m, "binder transactions:\n"); + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(proc, &binder_procs, proc_node) + print_binder_proc(m, proc, 0); + mutex_unlock(&binder_procs_lock); + + return 0; +} + +static int proc_show(struct seq_file *m, void *unused) +{ + struct binder_proc *itr; + int pid = (unsigned long)m->private; + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(itr, &binder_procs, proc_node) { + if (itr->pid == pid) { + seq_puts(m, "binder proc state:\n"); + print_binder_proc(m, itr, 1); + } + } + mutex_unlock(&binder_procs_lock); + + return 0; +} + +static void print_binder_transaction_log_entry(struct seq_file *m, + struct binder_transaction_log_entry *e) +{ + int debug_id = READ_ONCE(e->debug_id_done); + /* + * read barrier to guarantee debug_id_done read before + * we print the log values + */ + smp_rmb(); + seq_printf(m, + "%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d ret %d/%d l=%d", + e->debug_id, (e->call_type == 2) ? "reply" : + ((e->call_type == 1) ? "async" : "call "), e->from_proc, + e->from_thread, e->to_proc, e->to_thread, e->context_name, + e->to_node, e->target_handle, e->data_size, e->offsets_size, + e->return_error, e->return_error_param, + e->return_error_line); + /* + * read-barrier to guarantee read of debug_id_done after + * done printing the fields of the entry + */ + smp_rmb(); + seq_printf(m, debug_id && debug_id == READ_ONCE(e->debug_id_done) ? + "\n" : " (incomplete)\n"); +} + +static int transaction_log_show(struct seq_file *m, void *unused) +{ + struct binder_transaction_log *log = m->private; + unsigned int log_cur = atomic_read(&log->cur); + unsigned int count; + unsigned int cur; + int i; + + count = log_cur + 1; + cur = count < ARRAY_SIZE(log->entry) && !log->full ? + 0 : count % ARRAY_SIZE(log->entry); + if (count > ARRAY_SIZE(log->entry) || log->full) + count = ARRAY_SIZE(log->entry); + for (i = 0; i < count; i++) { + unsigned int index = cur++ % ARRAY_SIZE(log->entry); + + print_binder_transaction_log_entry(m, &log->entry[index]); + } + return 0; +} + +const struct file_operations binder_fops = { + .owner = THIS_MODULE, + .poll = binder_poll, + .unlocked_ioctl = binder_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .mmap = binder_mmap, + .open = binder_open, + .flush = binder_flush, + .release = binder_release, +}; + +DEFINE_SHOW_ATTRIBUTE(state); +DEFINE_SHOW_ATTRIBUTE(stats); +DEFINE_SHOW_ATTRIBUTE(transactions); +DEFINE_SHOW_ATTRIBUTE(transaction_log); + +const struct binder_debugfs_entry binder_debugfs_entries[] = { + { + .name = "state", + .mode = 0444, + .fops = &state_fops, + .data = NULL, + }, + { + .name = "stats", + .mode = 0444, + .fops = &stats_fops, + .data = NULL, + }, + { + .name = "transactions", + .mode = 0444, + .fops = &transactions_fops, + .data = NULL, + }, + { + .name = "transaction_log", + .mode = 0444, + .fops = &transaction_log_fops, + .data = &binder_transaction_log, + }, + { + .name = "failed_transaction_log", + .mode = 0444, + .fops = &transaction_log_fops, + .data = &binder_transaction_log_failed, + }, + {} /* terminator */ +}; + +static int __init init_binder_device(const char *name) +{ + int ret; + struct binder_device *binder_device; + + binder_device = kzalloc(sizeof(*binder_device), GFP_KERNEL); + if (!binder_device) + return -ENOMEM; + + binder_device->miscdev.fops = &binder_fops; + binder_device->miscdev.minor = MISC_DYNAMIC_MINOR; + binder_device->miscdev.name = name; + + refcount_set(&binder_device->ref, 1); + binder_device->context.binder_context_mgr_uid = INVALID_UID; + binder_device->context.name = name; + mutex_init(&binder_device->context.context_mgr_node_lock); + + ret = misc_register(&binder_device->miscdev); + if (ret < 0) { + kfree(binder_device); + return ret; + } + + hlist_add_head(&binder_device->hlist, &binder_devices); + + return ret; +} + +static int __init binder_init(void) +{ + int ret; + char *device_name, *device_tmp; + struct binder_device *device; + struct hlist_node *tmp; + char *device_names = NULL; + + ret = binder_alloc_shrinker_init(); + if (ret) + return ret; + + atomic_set(&binder_transaction_log.cur, ~0U); + atomic_set(&binder_transaction_log_failed.cur, ~0U); + + binder_debugfs_dir_entry_root = debugfs_create_dir("binder", NULL); + if (binder_debugfs_dir_entry_root) { + const struct binder_debugfs_entry *db_entry; + + binder_for_each_debugfs_entry(db_entry) + debugfs_create_file(db_entry->name, + db_entry->mode, + binder_debugfs_dir_entry_root, + db_entry->data, + db_entry->fops); + + binder_debugfs_dir_entry_proc = debugfs_create_dir("proc", + binder_debugfs_dir_entry_root); + } + + if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) && + strcmp(binder_devices_param, "") != 0) { + /* + * Copy the module_parameter string, because we don't want to + * tokenize it in-place. + */ + device_names = kstrdup(binder_devices_param, GFP_KERNEL); + if (!device_names) { + ret = -ENOMEM; + goto err_alloc_device_names_failed; + } + + device_tmp = device_names; + while ((device_name = strsep(&device_tmp, ","))) { + ret = init_binder_device(device_name); + if (ret) + goto err_init_binder_device_failed; + } + } + + ret = init_binderfs(); + if (ret) + goto err_init_binder_device_failed; + + return ret; + +err_init_binder_device_failed: + hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) { + misc_deregister(&device->miscdev); + hlist_del(&device->hlist); + kfree(device); + } + + kfree(device_names); + +err_alloc_device_names_failed: + debugfs_remove_recursive(binder_debugfs_dir_entry_root); + binder_alloc_shrinker_exit(); + + return ret; +} + +device_initcall(binder_init); + +#define CREATE_TRACE_POINTS +#include "binder_trace.h" + +MODULE_LICENSE("GPL v2"); diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c new file mode 100644 index 000000000..fcbb750b1 --- /dev/null +++ b/drivers/android/binder_alloc.c @@ -0,0 +1,1286 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* binder_alloc.c + * + * Android IPC Subsystem + * + * Copyright (C) 2007-2017 Google, Inc. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/list.h> +#include <linux/sched/mm.h> +#include <linux/module.h> +#include <linux/rtmutex.h> +#include <linux/rbtree.h> +#include <linux/seq_file.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/list_lru.h> +#include <linux/ratelimit.h> +#include <asm/cacheflush.h> +#include <linux/uaccess.h> +#include <linux/highmem.h> +#include <linux/sizes.h> +#include "binder_alloc.h" +#include "binder_trace.h" + +struct list_lru binder_alloc_lru; + +static DEFINE_MUTEX(binder_alloc_mmap_lock); + +enum { + BINDER_DEBUG_USER_ERROR = 1U << 0, + BINDER_DEBUG_OPEN_CLOSE = 1U << 1, + BINDER_DEBUG_BUFFER_ALLOC = 1U << 2, + BINDER_DEBUG_BUFFER_ALLOC_ASYNC = 1U << 3, +}; +static uint32_t binder_alloc_debug_mask = BINDER_DEBUG_USER_ERROR; + +module_param_named(debug_mask, binder_alloc_debug_mask, + uint, 0644); + +#define binder_alloc_debug(mask, x...) \ + do { \ + if (binder_alloc_debug_mask & mask) \ + pr_info_ratelimited(x); \ + } while (0) + +static struct binder_buffer *binder_buffer_next(struct binder_buffer *buffer) +{ + return list_entry(buffer->entry.next, struct binder_buffer, entry); +} + +static struct binder_buffer *binder_buffer_prev(struct binder_buffer *buffer) +{ + return list_entry(buffer->entry.prev, struct binder_buffer, entry); +} + +static size_t binder_alloc_buffer_size(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + if (list_is_last(&buffer->entry, &alloc->buffers)) + return alloc->buffer + alloc->buffer_size - buffer->user_data; + return binder_buffer_next(buffer)->user_data - buffer->user_data; +} + +static void binder_insert_free_buffer(struct binder_alloc *alloc, + struct binder_buffer *new_buffer) +{ + struct rb_node **p = &alloc->free_buffers.rb_node; + struct rb_node *parent = NULL; + struct binder_buffer *buffer; + size_t buffer_size; + size_t new_buffer_size; + + BUG_ON(!new_buffer->free); + + new_buffer_size = binder_alloc_buffer_size(alloc, new_buffer); + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: add free buffer, size %zd, at %pK\n", + alloc->pid, new_buffer_size, new_buffer); + + while (*p) { + parent = *p; + buffer = rb_entry(parent, struct binder_buffer, rb_node); + BUG_ON(!buffer->free); + + buffer_size = binder_alloc_buffer_size(alloc, buffer); + + if (new_buffer_size < buffer_size) + p = &parent->rb_left; + else + p = &parent->rb_right; + } + rb_link_node(&new_buffer->rb_node, parent, p); + rb_insert_color(&new_buffer->rb_node, &alloc->free_buffers); +} + +static void binder_insert_allocated_buffer_locked( + struct binder_alloc *alloc, struct binder_buffer *new_buffer) +{ + struct rb_node **p = &alloc->allocated_buffers.rb_node; + struct rb_node *parent = NULL; + struct binder_buffer *buffer; + + BUG_ON(new_buffer->free); + + while (*p) { + parent = *p; + buffer = rb_entry(parent, struct binder_buffer, rb_node); + BUG_ON(buffer->free); + + if (new_buffer->user_data < buffer->user_data) + p = &parent->rb_left; + else if (new_buffer->user_data > buffer->user_data) + p = &parent->rb_right; + else + BUG(); + } + rb_link_node(&new_buffer->rb_node, parent, p); + rb_insert_color(&new_buffer->rb_node, &alloc->allocated_buffers); +} + +static struct binder_buffer *binder_alloc_prepare_to_free_locked( + struct binder_alloc *alloc, + uintptr_t user_ptr) +{ + struct rb_node *n = alloc->allocated_buffers.rb_node; + struct binder_buffer *buffer; + void __user *uptr; + + uptr = (void __user *)user_ptr; + + while (n) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + BUG_ON(buffer->free); + + if (uptr < buffer->user_data) + n = n->rb_left; + else if (uptr > buffer->user_data) + n = n->rb_right; + else { + /* + * Guard against user threads attempting to + * free the buffer when in use by kernel or + * after it's already been freed. + */ + if (!buffer->allow_user_free) + return ERR_PTR(-EPERM); + buffer->allow_user_free = 0; + return buffer; + } + } + return NULL; +} + +/** + * binder_alloc_prepare_to_free() - get buffer given user ptr + * @alloc: binder_alloc for this proc + * @user_ptr: User pointer to buffer data + * + * Validate userspace pointer to buffer data and return buffer corresponding to + * that user pointer. Search the rb tree for buffer that matches user data + * pointer. + * + * Return: Pointer to buffer or NULL + */ +struct binder_buffer *binder_alloc_prepare_to_free(struct binder_alloc *alloc, + uintptr_t user_ptr) +{ + struct binder_buffer *buffer; + + mutex_lock(&alloc->mutex); + buffer = binder_alloc_prepare_to_free_locked(alloc, user_ptr); + mutex_unlock(&alloc->mutex); + return buffer; +} + +static int binder_update_page_range(struct binder_alloc *alloc, int allocate, + void __user *start, void __user *end) +{ + void __user *page_addr; + unsigned long user_page_addr; + struct binder_lru_page *page; + struct vm_area_struct *vma = NULL; + struct mm_struct *mm = NULL; + bool need_mm = false; + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: %s pages %pK-%pK\n", alloc->pid, + allocate ? "allocate" : "free", start, end); + + if (end <= start) + return 0; + + trace_binder_update_page_range(alloc, allocate, start, end); + + if (allocate == 0) + goto free_range; + + for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) { + page = &alloc->pages[(page_addr - alloc->buffer) / PAGE_SIZE]; + if (!page->page_ptr) { + need_mm = true; + break; + } + } + + if (need_mm && mmget_not_zero(alloc->mm)) + mm = alloc->mm; + + if (mm) { + mmap_write_lock(mm); + vma = alloc->vma; + } + + if (!vma && need_mm) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: binder_alloc_buf failed to map pages in userspace, no vma\n", + alloc->pid); + goto err_no_vma; + } + + for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) { + int ret; + bool on_lru; + size_t index; + + index = (page_addr - alloc->buffer) / PAGE_SIZE; + page = &alloc->pages[index]; + + if (page->page_ptr) { + trace_binder_alloc_lru_start(alloc, index); + + on_lru = list_lru_del(&binder_alloc_lru, &page->lru); + WARN_ON(!on_lru); + + trace_binder_alloc_lru_end(alloc, index); + continue; + } + + if (WARN_ON(!vma)) + goto err_page_ptr_cleared; + + trace_binder_alloc_page_start(alloc, index); + page->page_ptr = alloc_page(GFP_KERNEL | + __GFP_HIGHMEM | + __GFP_ZERO); + if (!page->page_ptr) { + pr_err("%d: binder_alloc_buf failed for page at %pK\n", + alloc->pid, page_addr); + goto err_alloc_page_failed; + } + page->alloc = alloc; + INIT_LIST_HEAD(&page->lru); + + user_page_addr = (uintptr_t)page_addr; + ret = vm_insert_page(vma, user_page_addr, page[0].page_ptr); + if (ret) { + pr_err("%d: binder_alloc_buf failed to map page at %lx in userspace\n", + alloc->pid, user_page_addr); + goto err_vm_insert_page_failed; + } + + if (index + 1 > alloc->pages_high) + alloc->pages_high = index + 1; + + trace_binder_alloc_page_end(alloc, index); + } + if (mm) { + mmap_write_unlock(mm); + mmput_async(mm); + } + return 0; + +free_range: + for (page_addr = end - PAGE_SIZE; 1; page_addr -= PAGE_SIZE) { + bool ret; + size_t index; + + index = (page_addr - alloc->buffer) / PAGE_SIZE; + page = &alloc->pages[index]; + + trace_binder_free_lru_start(alloc, index); + + ret = list_lru_add(&binder_alloc_lru, &page->lru); + WARN_ON(!ret); + + trace_binder_free_lru_end(alloc, index); + if (page_addr == start) + break; + continue; + +err_vm_insert_page_failed: + __free_page(page->page_ptr); + page->page_ptr = NULL; +err_alloc_page_failed: +err_page_ptr_cleared: + if (page_addr == start) + break; + } +err_no_vma: + if (mm) { + mmap_write_unlock(mm); + mmput_async(mm); + } + return vma ? -ENOMEM : -ESRCH; +} + +static inline void binder_alloc_set_vma(struct binder_alloc *alloc, + struct vm_area_struct *vma) +{ + /* pairs with smp_load_acquire in binder_alloc_get_vma() */ + smp_store_release(&alloc->vma, vma); +} + +static inline struct vm_area_struct *binder_alloc_get_vma( + struct binder_alloc *alloc) +{ + /* pairs with smp_store_release in binder_alloc_set_vma() */ + return smp_load_acquire(&alloc->vma); +} + +static bool debug_low_async_space_locked(struct binder_alloc *alloc, int pid) +{ + /* + * Find the amount and size of buffers allocated by the current caller; + * The idea is that once we cross the threshold, whoever is responsible + * for the low async space is likely to try to send another async txn, + * and at some point we'll catch them in the act. This is more efficient + * than keeping a map per pid. + */ + struct rb_node *n; + struct binder_buffer *buffer; + size_t total_alloc_size = 0; + size_t num_buffers = 0; + + for (n = rb_first(&alloc->allocated_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + if (buffer->pid != pid) + continue; + if (!buffer->async_transaction) + continue; + total_alloc_size += binder_alloc_buffer_size(alloc, buffer); + num_buffers++; + } + + /* + * Warn if this pid has more than 50 transactions, or more than 50% of + * async space (which is 25% of total buffer size). Oneway spam is only + * detected when the threshold is exceeded. + */ + if (num_buffers > 50 || total_alloc_size > alloc->buffer_size / 4) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: pid %d spamming oneway? %zd buffers allocated for a total size of %zd\n", + alloc->pid, pid, num_buffers, total_alloc_size); + if (!alloc->oneway_spam_detected) { + alloc->oneway_spam_detected = true; + return true; + } + } + return false; +} + +static struct binder_buffer *binder_alloc_new_buf_locked( + struct binder_alloc *alloc, + size_t data_size, + size_t offsets_size, + size_t extra_buffers_size, + int is_async, + int pid) +{ + struct rb_node *n = alloc->free_buffers.rb_node; + struct binder_buffer *buffer; + size_t buffer_size; + struct rb_node *best_fit = NULL; + void __user *has_page_addr; + void __user *end_page_addr; + size_t size, data_offsets_size; + int ret; + + /* Check binder_alloc is fully initialized */ + if (!binder_alloc_get_vma(alloc)) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: binder_alloc_buf, no vma\n", + alloc->pid); + return ERR_PTR(-ESRCH); + } + + data_offsets_size = ALIGN(data_size, sizeof(void *)) + + ALIGN(offsets_size, sizeof(void *)); + + if (data_offsets_size < data_size || data_offsets_size < offsets_size) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: got transaction with invalid size %zd-%zd\n", + alloc->pid, data_size, offsets_size); + return ERR_PTR(-EINVAL); + } + size = data_offsets_size + ALIGN(extra_buffers_size, sizeof(void *)); + if (size < data_offsets_size || size < extra_buffers_size) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: got transaction with invalid extra_buffers_size %zd\n", + alloc->pid, extra_buffers_size); + return ERR_PTR(-EINVAL); + } + + /* Pad 0-size buffers so they get assigned unique addresses */ + size = max(size, sizeof(void *)); + + if (is_async && alloc->free_async_space < size) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_alloc_buf size %zd failed, no async space left\n", + alloc->pid, size); + return ERR_PTR(-ENOSPC); + } + + while (n) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + BUG_ON(!buffer->free); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + + if (size < buffer_size) { + best_fit = n; + n = n->rb_left; + } else if (size > buffer_size) + n = n->rb_right; + else { + best_fit = n; + break; + } + } + if (best_fit == NULL) { + size_t allocated_buffers = 0; + size_t largest_alloc_size = 0; + size_t total_alloc_size = 0; + size_t free_buffers = 0; + size_t largest_free_size = 0; + size_t total_free_size = 0; + + for (n = rb_first(&alloc->allocated_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + allocated_buffers++; + total_alloc_size += buffer_size; + if (buffer_size > largest_alloc_size) + largest_alloc_size = buffer_size; + } + for (n = rb_first(&alloc->free_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + free_buffers++; + total_free_size += buffer_size; + if (buffer_size > largest_free_size) + largest_free_size = buffer_size; + } + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: binder_alloc_buf size %zd failed, no address space\n", + alloc->pid, size); + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n", + total_alloc_size, allocated_buffers, + largest_alloc_size, total_free_size, + free_buffers, largest_free_size); + return ERR_PTR(-ENOSPC); + } + if (n == NULL) { + buffer = rb_entry(best_fit, struct binder_buffer, rb_node); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + } + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_alloc_buf size %zd got buffer %pK size %zd\n", + alloc->pid, size, buffer, buffer_size); + + has_page_addr = (void __user *) + (((uintptr_t)buffer->user_data + buffer_size) & PAGE_MASK); + WARN_ON(n && buffer_size != size); + end_page_addr = + (void __user *)PAGE_ALIGN((uintptr_t)buffer->user_data + size); + if (end_page_addr > has_page_addr) + end_page_addr = has_page_addr; + ret = binder_update_page_range(alloc, 1, (void __user *) + PAGE_ALIGN((uintptr_t)buffer->user_data), end_page_addr); + if (ret) + return ERR_PTR(ret); + + if (buffer_size != size) { + struct binder_buffer *new_buffer; + + new_buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); + if (!new_buffer) { + pr_err("%s: %d failed to alloc new buffer struct\n", + __func__, alloc->pid); + goto err_alloc_buf_struct_failed; + } + new_buffer->user_data = (u8 __user *)buffer->user_data + size; + list_add(&new_buffer->entry, &buffer->entry); + new_buffer->free = 1; + binder_insert_free_buffer(alloc, new_buffer); + } + + rb_erase(best_fit, &alloc->free_buffers); + buffer->free = 0; + buffer->allow_user_free = 0; + binder_insert_allocated_buffer_locked(alloc, buffer); + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_alloc_buf size %zd got %pK\n", + alloc->pid, size, buffer); + buffer->data_size = data_size; + buffer->offsets_size = offsets_size; + buffer->async_transaction = is_async; + buffer->extra_buffers_size = extra_buffers_size; + buffer->pid = pid; + buffer->oneway_spam_suspect = false; + if (is_async) { + alloc->free_async_space -= size; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC, + "%d: binder_alloc_buf size %zd async free %zd\n", + alloc->pid, size, alloc->free_async_space); + if (alloc->free_async_space < alloc->buffer_size / 10) { + /* + * Start detecting spammers once we have less than 20% + * of async space left (which is less than 10% of total + * buffer size). + */ + buffer->oneway_spam_suspect = debug_low_async_space_locked(alloc, pid); + } else { + alloc->oneway_spam_detected = false; + } + } + return buffer; + +err_alloc_buf_struct_failed: + binder_update_page_range(alloc, 0, (void __user *) + PAGE_ALIGN((uintptr_t)buffer->user_data), + end_page_addr); + return ERR_PTR(-ENOMEM); +} + +/** + * binder_alloc_new_buf() - Allocate a new binder buffer + * @alloc: binder_alloc for this proc + * @data_size: size of user data buffer + * @offsets_size: user specified buffer offset + * @extra_buffers_size: size of extra space for meta-data (eg, security context) + * @is_async: buffer for async transaction + * @pid: pid to attribute allocation to (used for debugging) + * + * Allocate a new buffer given the requested sizes. Returns + * the kernel version of the buffer pointer. The size allocated + * is the sum of the three given sizes (each rounded up to + * pointer-sized boundary) + * + * Return: The allocated buffer or %ERR_PTR(-errno) if error + */ +struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, + size_t data_size, + size_t offsets_size, + size_t extra_buffers_size, + int is_async, + int pid) +{ + struct binder_buffer *buffer; + + mutex_lock(&alloc->mutex); + buffer = binder_alloc_new_buf_locked(alloc, data_size, offsets_size, + extra_buffers_size, is_async, pid); + mutex_unlock(&alloc->mutex); + return buffer; +} + +static void __user *buffer_start_page(struct binder_buffer *buffer) +{ + return (void __user *)((uintptr_t)buffer->user_data & PAGE_MASK); +} + +static void __user *prev_buffer_end_page(struct binder_buffer *buffer) +{ + return (void __user *) + (((uintptr_t)(buffer->user_data) - 1) & PAGE_MASK); +} + +static void binder_delete_free_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + struct binder_buffer *prev, *next = NULL; + bool to_free = true; + + BUG_ON(alloc->buffers.next == &buffer->entry); + prev = binder_buffer_prev(buffer); + BUG_ON(!prev->free); + if (prev_buffer_end_page(prev) == buffer_start_page(buffer)) { + to_free = false; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer %pK share page with %pK\n", + alloc->pid, buffer->user_data, + prev->user_data); + } + + if (!list_is_last(&buffer->entry, &alloc->buffers)) { + next = binder_buffer_next(buffer); + if (buffer_start_page(next) == buffer_start_page(buffer)) { + to_free = false; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer %pK share page with %pK\n", + alloc->pid, + buffer->user_data, + next->user_data); + } + } + + if (PAGE_ALIGNED(buffer->user_data)) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer start %pK is page aligned\n", + alloc->pid, buffer->user_data); + to_free = false; + } + + if (to_free) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer %pK do not share page with %pK or %pK\n", + alloc->pid, buffer->user_data, + prev->user_data, + next ? next->user_data : NULL); + binder_update_page_range(alloc, 0, buffer_start_page(buffer), + buffer_start_page(buffer) + PAGE_SIZE); + } + list_del(&buffer->entry); + kfree(buffer); +} + +static void binder_free_buf_locked(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + size_t size, buffer_size; + + buffer_size = binder_alloc_buffer_size(alloc, buffer); + + size = ALIGN(buffer->data_size, sizeof(void *)) + + ALIGN(buffer->offsets_size, sizeof(void *)) + + ALIGN(buffer->extra_buffers_size, sizeof(void *)); + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_free_buf %pK size %zd buffer_size %zd\n", + alloc->pid, buffer, size, buffer_size); + + BUG_ON(buffer->free); + BUG_ON(size > buffer_size); + BUG_ON(buffer->transaction != NULL); + BUG_ON(buffer->user_data < alloc->buffer); + BUG_ON(buffer->user_data > alloc->buffer + alloc->buffer_size); + + if (buffer->async_transaction) { + alloc->free_async_space += buffer_size; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC, + "%d: binder_free_buf size %zd async free %zd\n", + alloc->pid, size, alloc->free_async_space); + } + + binder_update_page_range(alloc, 0, + (void __user *)PAGE_ALIGN((uintptr_t)buffer->user_data), + (void __user *)(((uintptr_t) + buffer->user_data + buffer_size) & PAGE_MASK)); + + rb_erase(&buffer->rb_node, &alloc->allocated_buffers); + buffer->free = 1; + if (!list_is_last(&buffer->entry, &alloc->buffers)) { + struct binder_buffer *next = binder_buffer_next(buffer); + + if (next->free) { + rb_erase(&next->rb_node, &alloc->free_buffers); + binder_delete_free_buffer(alloc, next); + } + } + if (alloc->buffers.next != &buffer->entry) { + struct binder_buffer *prev = binder_buffer_prev(buffer); + + if (prev->free) { + binder_delete_free_buffer(alloc, buffer); + rb_erase(&prev->rb_node, &alloc->free_buffers); + buffer = prev; + } + } + binder_insert_free_buffer(alloc, buffer); +} + +static void binder_alloc_clear_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer); +/** + * binder_alloc_free_buf() - free a binder buffer + * @alloc: binder_alloc for this proc + * @buffer: kernel pointer to buffer + * + * Free the buffer allocated via binder_alloc_new_buf() + */ +void binder_alloc_free_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + /* + * We could eliminate the call to binder_alloc_clear_buf() + * from binder_alloc_deferred_release() by moving this to + * binder_free_buf_locked(). However, that could + * increase contention for the alloc mutex if clear_on_free + * is used frequently for large buffers. The mutex is not + * needed for correctness here. + */ + if (buffer->clear_on_free) { + binder_alloc_clear_buf(alloc, buffer); + buffer->clear_on_free = false; + } + mutex_lock(&alloc->mutex); + binder_free_buf_locked(alloc, buffer); + mutex_unlock(&alloc->mutex); +} + +/** + * binder_alloc_mmap_handler() - map virtual address space for proc + * @alloc: alloc structure for this proc + * @vma: vma passed to mmap() + * + * Called by binder_mmap() to initialize the space specified in + * vma for allocating binder buffers + * + * Return: + * 0 = success + * -EBUSY = address space already mapped + * -ENOMEM = failed to map memory to given address space + */ +int binder_alloc_mmap_handler(struct binder_alloc *alloc, + struct vm_area_struct *vma) +{ + int ret; + const char *failure_string; + struct binder_buffer *buffer; + + if (unlikely(vma->vm_mm != alloc->mm)) { + ret = -EINVAL; + failure_string = "invalid vma->vm_mm"; + goto err_invalid_mm; + } + + mutex_lock(&binder_alloc_mmap_lock); + if (alloc->buffer_size) { + ret = -EBUSY; + failure_string = "already mapped"; + goto err_already_mapped; + } + alloc->buffer_size = min_t(unsigned long, vma->vm_end - vma->vm_start, + SZ_4M); + mutex_unlock(&binder_alloc_mmap_lock); + + alloc->buffer = (void __user *)vma->vm_start; + + alloc->pages = kcalloc(alloc->buffer_size / PAGE_SIZE, + sizeof(alloc->pages[0]), + GFP_KERNEL); + if (alloc->pages == NULL) { + ret = -ENOMEM; + failure_string = "alloc page array"; + goto err_alloc_pages_failed; + } + + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); + if (!buffer) { + ret = -ENOMEM; + failure_string = "alloc buffer struct"; + goto err_alloc_buf_struct_failed; + } + + buffer->user_data = alloc->buffer; + list_add(&buffer->entry, &alloc->buffers); + buffer->free = 1; + binder_insert_free_buffer(alloc, buffer); + alloc->free_async_space = alloc->buffer_size / 2; + + /* Signal binder_alloc is fully initialized */ + binder_alloc_set_vma(alloc, vma); + + return 0; + +err_alloc_buf_struct_failed: + kfree(alloc->pages); + alloc->pages = NULL; +err_alloc_pages_failed: + alloc->buffer = NULL; + mutex_lock(&binder_alloc_mmap_lock); + alloc->buffer_size = 0; +err_already_mapped: + mutex_unlock(&binder_alloc_mmap_lock); +err_invalid_mm: + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%s: %d %lx-%lx %s failed %d\n", __func__, + alloc->pid, vma->vm_start, vma->vm_end, + failure_string, ret); + return ret; +} + + +void binder_alloc_deferred_release(struct binder_alloc *alloc) +{ + struct rb_node *n; + int buffers, page_count; + struct binder_buffer *buffer; + + buffers = 0; + mutex_lock(&alloc->mutex); + BUG_ON(alloc->vma); + + while ((n = rb_first(&alloc->allocated_buffers))) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + + /* Transaction should already have been freed */ + BUG_ON(buffer->transaction); + + if (buffer->clear_on_free) { + binder_alloc_clear_buf(alloc, buffer); + buffer->clear_on_free = false; + } + binder_free_buf_locked(alloc, buffer); + buffers++; + } + + while (!list_empty(&alloc->buffers)) { + buffer = list_first_entry(&alloc->buffers, + struct binder_buffer, entry); + WARN_ON(!buffer->free); + + list_del(&buffer->entry); + WARN_ON_ONCE(!list_empty(&alloc->buffers)); + kfree(buffer); + } + + page_count = 0; + if (alloc->pages) { + int i; + + for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { + void __user *page_addr; + bool on_lru; + + if (!alloc->pages[i].page_ptr) + continue; + + on_lru = list_lru_del(&binder_alloc_lru, + &alloc->pages[i].lru); + page_addr = alloc->buffer + i * PAGE_SIZE; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%s: %d: page %d at %pK %s\n", + __func__, alloc->pid, i, page_addr, + on_lru ? "on lru" : "active"); + __free_page(alloc->pages[i].page_ptr); + page_count++; + } + kfree(alloc->pages); + } + mutex_unlock(&alloc->mutex); + if (alloc->mm) + mmdrop(alloc->mm); + + binder_alloc_debug(BINDER_DEBUG_OPEN_CLOSE, + "%s: %d buffers %d, pages %d\n", + __func__, alloc->pid, buffers, page_count); +} + +static void print_binder_buffer(struct seq_file *m, const char *prefix, + struct binder_buffer *buffer) +{ + seq_printf(m, "%s %d: %pK size %zd:%zd:%zd %s\n", + prefix, buffer->debug_id, buffer->user_data, + buffer->data_size, buffer->offsets_size, + buffer->extra_buffers_size, + buffer->transaction ? "active" : "delivered"); +} + +/** + * binder_alloc_print_allocated() - print buffer info + * @m: seq_file for output via seq_printf() + * @alloc: binder_alloc for this proc + * + * Prints information about every buffer associated with + * the binder_alloc state to the given seq_file + */ +void binder_alloc_print_allocated(struct seq_file *m, + struct binder_alloc *alloc) +{ + struct rb_node *n; + + mutex_lock(&alloc->mutex); + for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n)) + print_binder_buffer(m, " buffer", + rb_entry(n, struct binder_buffer, rb_node)); + mutex_unlock(&alloc->mutex); +} + +/** + * binder_alloc_print_pages() - print page usage + * @m: seq_file for output via seq_printf() + * @alloc: binder_alloc for this proc + */ +void binder_alloc_print_pages(struct seq_file *m, + struct binder_alloc *alloc) +{ + struct binder_lru_page *page; + int i; + int active = 0; + int lru = 0; + int free = 0; + + mutex_lock(&alloc->mutex); + /* + * Make sure the binder_alloc is fully initialized, otherwise we might + * read inconsistent state. + */ + if (binder_alloc_get_vma(alloc) != NULL) { + for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { + page = &alloc->pages[i]; + if (!page->page_ptr) + free++; + else if (list_empty(&page->lru)) + active++; + else + lru++; + } + } + mutex_unlock(&alloc->mutex); + seq_printf(m, " pages: %d:%d:%d\n", active, lru, free); + seq_printf(m, " pages high watermark: %zu\n", alloc->pages_high); +} + +/** + * binder_alloc_get_allocated_count() - return count of buffers + * @alloc: binder_alloc for this proc + * + * Return: count of allocated buffers + */ +int binder_alloc_get_allocated_count(struct binder_alloc *alloc) +{ + struct rb_node *n; + int count = 0; + + mutex_lock(&alloc->mutex); + for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n)) + count++; + mutex_unlock(&alloc->mutex); + return count; +} + + +/** + * binder_alloc_vma_close() - invalidate address space + * @alloc: binder_alloc for this proc + * + * Called from binder_vma_close() when releasing address space. + * Clears alloc->vma to prevent new incoming transactions from + * allocating more buffers. + */ +void binder_alloc_vma_close(struct binder_alloc *alloc) +{ + binder_alloc_set_vma(alloc, NULL); +} + +/** + * binder_alloc_free_page() - shrinker callback to free pages + * @item: item to free + * @lock: lock protecting the item + * @cb_arg: callback argument + * + * Called from list_lru_walk() in binder_shrink_scan() to free + * up pages when the system is under memory pressure. + */ +enum lru_status binder_alloc_free_page(struct list_head *item, + struct list_lru_one *lru, + spinlock_t *lock, + void *cb_arg) + __must_hold(lock) +{ + struct mm_struct *mm = NULL; + struct binder_lru_page *page = container_of(item, + struct binder_lru_page, + lru); + struct binder_alloc *alloc; + uintptr_t page_addr; + size_t index; + struct vm_area_struct *vma; + + alloc = page->alloc; + if (!mutex_trylock(&alloc->mutex)) + goto err_get_alloc_mutex_failed; + + if (!page->page_ptr) + goto err_page_already_freed; + + index = page - alloc->pages; + page_addr = (uintptr_t)alloc->buffer + index * PAGE_SIZE; + + mm = alloc->mm; + if (!mmget_not_zero(mm)) + goto err_mmget; + if (!mmap_read_trylock(mm)) + goto err_mmap_read_lock_failed; + vma = vma_lookup(mm, page_addr); + if (vma && vma != binder_alloc_get_vma(alloc)) + goto err_invalid_vma; + + list_lru_isolate(lru, item); + spin_unlock(lock); + + if (vma) { + trace_binder_unmap_user_start(alloc, index); + + zap_page_range(vma, page_addr, PAGE_SIZE); + + trace_binder_unmap_user_end(alloc, index); + } + mmap_read_unlock(mm); + mmput_async(mm); + + trace_binder_unmap_kernel_start(alloc, index); + + __free_page(page->page_ptr); + page->page_ptr = NULL; + + trace_binder_unmap_kernel_end(alloc, index); + + spin_lock(lock); + mutex_unlock(&alloc->mutex); + return LRU_REMOVED_RETRY; + +err_invalid_vma: + mmap_read_unlock(mm); +err_mmap_read_lock_failed: + mmput_async(mm); +err_mmget: +err_page_already_freed: + mutex_unlock(&alloc->mutex); +err_get_alloc_mutex_failed: + return LRU_SKIP; +} + +static unsigned long +binder_shrink_count(struct shrinker *shrink, struct shrink_control *sc) +{ + return list_lru_count(&binder_alloc_lru); +} + +static unsigned long +binder_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) +{ + return list_lru_walk(&binder_alloc_lru, binder_alloc_free_page, + NULL, sc->nr_to_scan); +} + +static struct shrinker binder_shrinker = { + .count_objects = binder_shrink_count, + .scan_objects = binder_shrink_scan, + .seeks = DEFAULT_SEEKS, +}; + +/** + * binder_alloc_init() - called by binder_open() for per-proc initialization + * @alloc: binder_alloc for this proc + * + * Called from binder_open() to initialize binder_alloc fields for + * new binder proc + */ +void binder_alloc_init(struct binder_alloc *alloc) +{ + alloc->pid = current->group_leader->pid; + alloc->mm = current->mm; + mmgrab(alloc->mm); + mutex_init(&alloc->mutex); + INIT_LIST_HEAD(&alloc->buffers); +} + +int binder_alloc_shrinker_init(void) +{ + int ret = list_lru_init(&binder_alloc_lru); + + if (ret == 0) { + ret = register_shrinker(&binder_shrinker, "android-binder"); + if (ret) + list_lru_destroy(&binder_alloc_lru); + } + return ret; +} + +void binder_alloc_shrinker_exit(void) +{ + unregister_shrinker(&binder_shrinker); + list_lru_destroy(&binder_alloc_lru); +} + +/** + * check_buffer() - verify that buffer/offset is safe to access + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be accessed + * @offset: offset into @buffer data + * @bytes: bytes to access from offset + * + * Check that the @offset/@bytes are within the size of the given + * @buffer and that the buffer is currently active and not freeable. + * Offsets must also be multiples of sizeof(u32). The kernel is + * allowed to touch the buffer in two cases: + * + * 1) when the buffer is being created: + * (buffer->free == 0 && buffer->allow_user_free == 0) + * 2) when the buffer is being torn down: + * (buffer->free == 0 && buffer->transaction == NULL). + * + * Return: true if the buffer is safe to access + */ +static inline bool check_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t offset, size_t bytes) +{ + size_t buffer_size = binder_alloc_buffer_size(alloc, buffer); + + return buffer_size >= bytes && + offset <= buffer_size - bytes && + IS_ALIGNED(offset, sizeof(u32)) && + !buffer->free && + (!buffer->allow_user_free || !buffer->transaction); +} + +/** + * binder_alloc_get_page() - get kernel pointer for given buffer offset + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be accessed + * @buffer_offset: offset into @buffer data + * @pgoffp: address to copy final page offset to + * + * Lookup the struct page corresponding to the address + * at @buffer_offset into @buffer->user_data. If @pgoffp is not + * NULL, the byte-offset into the page is written there. + * + * The caller is responsible to ensure that the offset points + * to a valid address within the @buffer and that @buffer is + * not freeable by the user. Since it can't be freed, we are + * guaranteed that the corresponding elements of @alloc->pages[] + * cannot change. + * + * Return: struct page + */ +static struct page *binder_alloc_get_page(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + pgoff_t *pgoffp) +{ + binder_size_t buffer_space_offset = buffer_offset + + (buffer->user_data - alloc->buffer); + pgoff_t pgoff = buffer_space_offset & ~PAGE_MASK; + size_t index = buffer_space_offset >> PAGE_SHIFT; + struct binder_lru_page *lru_page; + + lru_page = &alloc->pages[index]; + *pgoffp = pgoff; + return lru_page->page_ptr; +} + +/** + * binder_alloc_clear_buf() - zero out buffer + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be cleared + * + * memset the given buffer to 0 + */ +static void binder_alloc_clear_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + size_t bytes = binder_alloc_buffer_size(alloc, buffer); + binder_size_t buffer_offset = 0; + + while (bytes) { + unsigned long size; + struct page *page; + pgoff_t pgoff; + + page = binder_alloc_get_page(alloc, buffer, + buffer_offset, &pgoff); + size = min_t(size_t, bytes, PAGE_SIZE - pgoff); + memset_page(page, pgoff, 0, size); + bytes -= size; + buffer_offset += size; + } +} + +/** + * binder_alloc_copy_user_to_buffer() - copy src user to tgt user + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be accessed + * @buffer_offset: offset into @buffer data + * @from: userspace pointer to source buffer + * @bytes: bytes to copy + * + * Copy bytes from source userspace to target buffer. + * + * Return: bytes remaining to be copied + */ +unsigned long +binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + const void __user *from, + size_t bytes) +{ + if (!check_buffer(alloc, buffer, buffer_offset, bytes)) + return bytes; + + while (bytes) { + unsigned long size; + unsigned long ret; + struct page *page; + pgoff_t pgoff; + void *kptr; + + page = binder_alloc_get_page(alloc, buffer, + buffer_offset, &pgoff); + size = min_t(size_t, bytes, PAGE_SIZE - pgoff); + kptr = kmap_local_page(page) + pgoff; + ret = copy_from_user(kptr, from, size); + kunmap_local(kptr); + if (ret) + return bytes - size + ret; + bytes -= size; + from += size; + buffer_offset += size; + } + return 0; +} + +static int binder_alloc_do_buffer_copy(struct binder_alloc *alloc, + bool to_buffer, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + void *ptr, + size_t bytes) +{ + /* All copies must be 32-bit aligned and 32-bit size */ + if (!check_buffer(alloc, buffer, buffer_offset, bytes)) + return -EINVAL; + + while (bytes) { + unsigned long size; + struct page *page; + pgoff_t pgoff; + + page = binder_alloc_get_page(alloc, buffer, + buffer_offset, &pgoff); + size = min_t(size_t, bytes, PAGE_SIZE - pgoff); + if (to_buffer) + memcpy_to_page(page, pgoff, ptr, size); + else + memcpy_from_page(ptr, page, pgoff, size); + bytes -= size; + pgoff = 0; + ptr = ptr + size; + buffer_offset += size; + } + return 0; +} + +int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + void *src, + size_t bytes) +{ + return binder_alloc_do_buffer_copy(alloc, true, buffer, buffer_offset, + src, bytes); +} + +int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, + void *dest, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + size_t bytes) +{ + return binder_alloc_do_buffer_copy(alloc, false, buffer, buffer_offset, + dest, bytes); +} + diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h new file mode 100644 index 000000000..dc1e2b01d --- /dev/null +++ b/drivers/android/binder_alloc.h @@ -0,0 +1,185 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2017 Google, Inc. + */ + +#ifndef _LINUX_BINDER_ALLOC_H +#define _LINUX_BINDER_ALLOC_H + +#include <linux/rbtree.h> +#include <linux/list.h> +#include <linux/mm.h> +#include <linux/rtmutex.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/list_lru.h> +#include <uapi/linux/android/binder.h> + +extern struct list_lru binder_alloc_lru; +struct binder_transaction; + +/** + * struct binder_buffer - buffer used for binder transactions + * @entry: entry alloc->buffers + * @rb_node: node for allocated_buffers/free_buffers rb trees + * @free: %true if buffer is free + * @clear_on_free: %true if buffer must be zeroed after use + * @allow_user_free: %true if user is allowed to free buffer + * @async_transaction: %true if buffer is in use for an async txn + * @oneway_spam_suspect: %true if total async allocate size just exceed + * spamming detect threshold + * @debug_id: unique ID for debugging + * @transaction: pointer to associated struct binder_transaction + * @target_node: struct binder_node associated with this buffer + * @data_size: size of @transaction data + * @offsets_size: size of array of offsets + * @extra_buffers_size: size of space for other objects (like sg lists) + * @user_data: user pointer to base of buffer space + * @pid: pid to attribute the buffer to (caller) + * + * Bookkeeping structure for binder transaction buffers + */ +struct binder_buffer { + struct list_head entry; /* free and allocated entries by address */ + struct rb_node rb_node; /* free entry by size or allocated entry */ + /* by address */ + unsigned free:1; + unsigned clear_on_free:1; + unsigned allow_user_free:1; + unsigned async_transaction:1; + unsigned oneway_spam_suspect:1; + unsigned debug_id:27; + + struct binder_transaction *transaction; + + struct binder_node *target_node; + size_t data_size; + size_t offsets_size; + size_t extra_buffers_size; + void __user *user_data; + int pid; +}; + +/** + * struct binder_lru_page - page object used for binder shrinker + * @page_ptr: pointer to physical page in mmap'd space + * @lru: entry in binder_alloc_lru + * @alloc: binder_alloc for a proc + */ +struct binder_lru_page { + struct list_head lru; + struct page *page_ptr; + struct binder_alloc *alloc; +}; + +/** + * struct binder_alloc - per-binder proc state for binder allocator + * @mutex: protects binder_alloc fields + * @vma: vm_area_struct passed to mmap_handler + * (invariant after mmap) + * @mm: copy of task->mm (invariant after open) + * @buffer: base of per-proc address space mapped via mmap + * @buffers: list of all buffers for this proc + * @free_buffers: rb tree of buffers available for allocation + * sorted by size + * @allocated_buffers: rb tree of allocated buffers sorted by address + * @free_async_space: VA space available for async buffers. This is + * initialized at mmap time to 1/2 the full VA space + * @pages: array of binder_lru_page + * @buffer_size: size of address space specified via mmap + * @pid: pid for associated binder_proc (invariant after init) + * @pages_high: high watermark of offset in @pages + * @oneway_spam_detected: %true if oneway spam detection fired, clear that + * flag once the async buffer has returned to a healthy state + * + * Bookkeeping structure for per-proc address space management for binder + * buffers. It is normally initialized during binder_init() and binder_mmap() + * calls. The address space is used for both user-visible buffers and for + * struct binder_buffer objects used to track the user buffers + */ +struct binder_alloc { + struct mutex mutex; + struct vm_area_struct *vma; + struct mm_struct *mm; + void __user *buffer; + struct list_head buffers; + struct rb_root free_buffers; + struct rb_root allocated_buffers; + size_t free_async_space; + struct binder_lru_page *pages; + size_t buffer_size; + int pid; + size_t pages_high; + bool oneway_spam_detected; +}; + +#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST +void binder_selftest_alloc(struct binder_alloc *alloc); +#else +static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} +#endif +enum lru_status binder_alloc_free_page(struct list_head *item, + struct list_lru_one *lru, + spinlock_t *lock, void *cb_arg); +extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, + size_t data_size, + size_t offsets_size, + size_t extra_buffers_size, + int is_async, + int pid); +extern void binder_alloc_init(struct binder_alloc *alloc); +extern int binder_alloc_shrinker_init(void); +extern void binder_alloc_shrinker_exit(void); +extern void binder_alloc_vma_close(struct binder_alloc *alloc); +extern struct binder_buffer * +binder_alloc_prepare_to_free(struct binder_alloc *alloc, + uintptr_t user_ptr); +extern void binder_alloc_free_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer); +extern int binder_alloc_mmap_handler(struct binder_alloc *alloc, + struct vm_area_struct *vma); +extern void binder_alloc_deferred_release(struct binder_alloc *alloc); +extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc); +extern void binder_alloc_print_allocated(struct seq_file *m, + struct binder_alloc *alloc); +void binder_alloc_print_pages(struct seq_file *m, + struct binder_alloc *alloc); + +/** + * binder_alloc_get_free_async_space() - get free space available for async + * @alloc: binder_alloc for this proc + * + * Return: the bytes remaining in the address-space for async transactions + */ +static inline size_t +binder_alloc_get_free_async_space(struct binder_alloc *alloc) +{ + size_t free_async_space; + + mutex_lock(&alloc->mutex); + free_async_space = alloc->free_async_space; + mutex_unlock(&alloc->mutex); + return free_async_space; +} + +unsigned long +binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + const void __user *from, + size_t bytes); + +int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + void *src, + size_t bytes); + +int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, + void *dest, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + size_t bytes); + +#endif /* _LINUX_BINDER_ALLOC_H */ + diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c new file mode 100644 index 000000000..c2b323bc3 --- /dev/null +++ b/drivers/android/binder_alloc_selftest.c @@ -0,0 +1,302 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* binder_alloc_selftest.c + * + * Android IPC Subsystem + * + * Copyright (C) 2017 Google, Inc. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/mm_types.h> +#include <linux/err.h> +#include "binder_alloc.h" + +#define BUFFER_NUM 5 +#define BUFFER_MIN_SIZE (PAGE_SIZE / 8) + +static bool binder_selftest_run = true; +static int binder_selftest_failures; +static DEFINE_MUTEX(binder_selftest_lock); + +/** + * enum buf_end_align_type - Page alignment of a buffer + * end with regard to the end of the previous buffer. + * + * In the pictures below, buf2 refers to the buffer we + * are aligning. buf1 refers to previous buffer by addr. + * Symbol [ means the start of a buffer, ] means the end + * of a buffer, and | means page boundaries. + */ +enum buf_end_align_type { + /** + * @SAME_PAGE_UNALIGNED: The end of this buffer is on + * the same page as the end of the previous buffer and + * is not page aligned. Examples: + * buf1 ][ buf2 ][ ... + * buf1 ]|[ buf2 ][ ... + */ + SAME_PAGE_UNALIGNED = 0, + /** + * @SAME_PAGE_ALIGNED: When the end of the previous buffer + * is not page aligned, the end of this buffer is on the + * same page as the end of the previous buffer and is page + * aligned. When the previous buffer is page aligned, the + * end of this buffer is aligned to the next page boundary. + * Examples: + * buf1 ][ buf2 ]| ... + * buf1 ]|[ buf2 ]| ... + */ + SAME_PAGE_ALIGNED, + /** + * @NEXT_PAGE_UNALIGNED: The end of this buffer is on + * the page next to the end of the previous buffer and + * is not page aligned. Examples: + * buf1 ][ buf2 | buf2 ][ ... + * buf1 ]|[ buf2 | buf2 ][ ... + */ + NEXT_PAGE_UNALIGNED, + /** + * @NEXT_PAGE_ALIGNED: The end of this buffer is on + * the page next to the end of the previous buffer and + * is page aligned. Examples: + * buf1 ][ buf2 | buf2 ]| ... + * buf1 ]|[ buf2 | buf2 ]| ... + */ + NEXT_PAGE_ALIGNED, + /** + * @NEXT_NEXT_UNALIGNED: The end of this buffer is on + * the page that follows the page after the end of the + * previous buffer and is not page aligned. Examples: + * buf1 ][ buf2 | buf2 | buf2 ][ ... + * buf1 ]|[ buf2 | buf2 | buf2 ][ ... + */ + NEXT_NEXT_UNALIGNED, + LOOP_END, +}; + +static void pr_err_size_seq(size_t *sizes, int *seq) +{ + int i; + + pr_err("alloc sizes: "); + for (i = 0; i < BUFFER_NUM; i++) + pr_cont("[%zu]", sizes[i]); + pr_cont("\n"); + pr_err("free seq: "); + for (i = 0; i < BUFFER_NUM; i++) + pr_cont("[%d]", seq[i]); + pr_cont("\n"); +} + +static bool check_buffer_pages_allocated(struct binder_alloc *alloc, + struct binder_buffer *buffer, + size_t size) +{ + void __user *page_addr; + void __user *end; + int page_index; + + end = (void __user *)PAGE_ALIGN((uintptr_t)buffer->user_data + size); + page_addr = buffer->user_data; + for (; page_addr < end; page_addr += PAGE_SIZE) { + page_index = (page_addr - alloc->buffer) / PAGE_SIZE; + if (!alloc->pages[page_index].page_ptr || + !list_empty(&alloc->pages[page_index].lru)) { + pr_err("expect alloc but is %s at page index %d\n", + alloc->pages[page_index].page_ptr ? + "lru" : "free", page_index); + return false; + } + } + return true; +} + +static void binder_selftest_alloc_buf(struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq) +{ + int i; + + for (i = 0; i < BUFFER_NUM; i++) { + buffers[i] = binder_alloc_new_buf(alloc, sizes[i], 0, 0, 0, 0); + if (IS_ERR(buffers[i]) || + !check_buffer_pages_allocated(alloc, buffers[i], + sizes[i])) { + pr_err_size_seq(sizes, seq); + binder_selftest_failures++; + } + } +} + +static void binder_selftest_free_buf(struct binder_alloc *alloc, + struct binder_buffer *buffers[], + size_t *sizes, int *seq, size_t end) +{ + int i; + + for (i = 0; i < BUFFER_NUM; i++) + binder_alloc_free_buf(alloc, buffers[seq[i]]); + + for (i = 0; i < end / PAGE_SIZE; i++) { + /** + * Error message on a free page can be false positive + * if binder shrinker ran during binder_alloc_free_buf + * calls above. + */ + if (list_empty(&alloc->pages[i].lru)) { + pr_err_size_seq(sizes, seq); + pr_err("expect lru but is %s at page index %d\n", + alloc->pages[i].page_ptr ? "alloc" : "free", i); + binder_selftest_failures++; + } + } +} + +static void binder_selftest_free_page(struct binder_alloc *alloc) +{ + int i; + unsigned long count; + + while ((count = list_lru_count(&binder_alloc_lru))) { + list_lru_walk(&binder_alloc_lru, binder_alloc_free_page, + NULL, count); + } + + for (i = 0; i < (alloc->buffer_size / PAGE_SIZE); i++) { + if (alloc->pages[i].page_ptr) { + pr_err("expect free but is %s at page index %d\n", + list_empty(&alloc->pages[i].lru) ? + "alloc" : "lru", i); + binder_selftest_failures++; + } + } +} + +static void binder_selftest_alloc_free(struct binder_alloc *alloc, + size_t *sizes, int *seq, size_t end) +{ + struct binder_buffer *buffers[BUFFER_NUM]; + + binder_selftest_alloc_buf(alloc, buffers, sizes, seq); + binder_selftest_free_buf(alloc, buffers, sizes, seq, end); + + /* Allocate from lru. */ + binder_selftest_alloc_buf(alloc, buffers, sizes, seq); + if (list_lru_count(&binder_alloc_lru)) + pr_err("lru list should be empty but is not\n"); + + binder_selftest_free_buf(alloc, buffers, sizes, seq, end); + binder_selftest_free_page(alloc); +} + +static bool is_dup(int *seq, int index, int val) +{ + int i; + + for (i = 0; i < index; i++) { + if (seq[i] == val) + return true; + } + return false; +} + +/* Generate BUFFER_NUM factorial free orders. */ +static void binder_selftest_free_seq(struct binder_alloc *alloc, + size_t *sizes, int *seq, + int index, size_t end) +{ + int i; + + if (index == BUFFER_NUM) { + binder_selftest_alloc_free(alloc, sizes, seq, end); + return; + } + for (i = 0; i < BUFFER_NUM; i++) { + if (is_dup(seq, index, i)) + continue; + seq[index] = i; + binder_selftest_free_seq(alloc, sizes, seq, index + 1, end); + } +} + +static void binder_selftest_alloc_size(struct binder_alloc *alloc, + size_t *end_offset) +{ + int i; + int seq[BUFFER_NUM] = {0}; + size_t front_sizes[BUFFER_NUM]; + size_t back_sizes[BUFFER_NUM]; + size_t last_offset, offset = 0; + + for (i = 0; i < BUFFER_NUM; i++) { + last_offset = offset; + offset = end_offset[i]; + front_sizes[i] = offset - last_offset; + back_sizes[BUFFER_NUM - i - 1] = front_sizes[i]; + } + /* + * Buffers share the first or last few pages. + * Only BUFFER_NUM - 1 buffer sizes are adjustable since + * we need one giant buffer before getting to the last page. + */ + back_sizes[0] += alloc->buffer_size - end_offset[BUFFER_NUM - 1]; + binder_selftest_free_seq(alloc, front_sizes, seq, 0, + end_offset[BUFFER_NUM - 1]); + binder_selftest_free_seq(alloc, back_sizes, seq, 0, alloc->buffer_size); +} + +static void binder_selftest_alloc_offset(struct binder_alloc *alloc, + size_t *end_offset, int index) +{ + int align; + size_t end, prev; + + if (index == BUFFER_NUM) { + binder_selftest_alloc_size(alloc, end_offset); + return; + } + prev = index == 0 ? 0 : end_offset[index - 1]; + end = prev; + + BUILD_BUG_ON(BUFFER_MIN_SIZE * BUFFER_NUM >= PAGE_SIZE); + + for (align = SAME_PAGE_UNALIGNED; align < LOOP_END; align++) { + if (align % 2) + end = ALIGN(end, PAGE_SIZE); + else + end += BUFFER_MIN_SIZE; + end_offset[index] = end; + binder_selftest_alloc_offset(alloc, end_offset, index + 1); + } +} + +/** + * binder_selftest_alloc() - Test alloc and free of buffer pages. + * @alloc: Pointer to alloc struct. + * + * Allocate BUFFER_NUM buffers to cover all page alignment cases, + * then free them in all orders possible. Check that pages are + * correctly allocated, put onto lru when buffers are freed, and + * are freed when binder_alloc_free_page is called. + */ +void binder_selftest_alloc(struct binder_alloc *alloc) +{ + size_t end_offset[BUFFER_NUM]; + + if (!binder_selftest_run) + return; + mutex_lock(&binder_selftest_lock); + if (!binder_selftest_run || !alloc->vma) + goto done; + pr_info("STARTED\n"); + binder_selftest_alloc_offset(alloc, end_offset, 0); + binder_selftest_run = false; + if (binder_selftest_failures > 0) + pr_info("%d tests FAILED\n", binder_selftest_failures); + else + pr_info("PASSED\n"); + +done: + mutex_unlock(&binder_selftest_lock); +} diff --git a/drivers/android/binder_internal.h b/drivers/android/binder_internal.h new file mode 100644 index 000000000..abe19d88c --- /dev/null +++ b/drivers/android/binder_internal.h @@ -0,0 +1,561 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _LINUX_BINDER_INTERNAL_H +#define _LINUX_BINDER_INTERNAL_H + +#include <linux/export.h> +#include <linux/fs.h> +#include <linux/list.h> +#include <linux/miscdevice.h> +#include <linux/mutex.h> +#include <linux/refcount.h> +#include <linux/stddef.h> +#include <linux/types.h> +#include <linux/uidgid.h> +#include <uapi/linux/android/binderfs.h> +#include "binder_alloc.h" + +struct binder_context { + struct binder_node *binder_context_mgr_node; + struct mutex context_mgr_node_lock; + kuid_t binder_context_mgr_uid; + const char *name; +}; + +/** + * struct binder_device - information about a binder device node + * @hlist: list of binder devices (only used for devices requested via + * CONFIG_ANDROID_BINDER_DEVICES) + * @miscdev: information about a binder character device node + * @context: binder context information + * @binderfs_inode: This is the inode of the root dentry of the super block + * belonging to a binderfs mount. + */ +struct binder_device { + struct hlist_node hlist; + struct miscdevice miscdev; + struct binder_context context; + struct inode *binderfs_inode; + refcount_t ref; +}; + +/** + * binderfs_mount_opts - mount options for binderfs + * @max: maximum number of allocatable binderfs binder devices + * @stats_mode: enable binder stats in binderfs. + */ +struct binderfs_mount_opts { + int max; + int stats_mode; +}; + +/** + * binderfs_info - information about a binderfs mount + * @ipc_ns: The ipc namespace the binderfs mount belongs to. + * @control_dentry: This records the dentry of this binderfs mount + * binder-control device. + * @root_uid: uid that needs to be used when a new binder device is + * created. + * @root_gid: gid that needs to be used when a new binder device is + * created. + * @mount_opts: The mount options in use. + * @device_count: The current number of allocated binder devices. + * @proc_log_dir: Pointer to the directory dentry containing process-specific + * logs. + */ +struct binderfs_info { + struct ipc_namespace *ipc_ns; + struct dentry *control_dentry; + kuid_t root_uid; + kgid_t root_gid; + struct binderfs_mount_opts mount_opts; + int device_count; + struct dentry *proc_log_dir; +}; + +extern const struct file_operations binder_fops; + +extern char *binder_devices_param; + +#ifdef CONFIG_ANDROID_BINDERFS +extern bool is_binderfs_device(const struct inode *inode); +extern struct dentry *binderfs_create_file(struct dentry *dir, const char *name, + const struct file_operations *fops, + void *data); +extern void binderfs_remove_file(struct dentry *dentry); +#else +static inline bool is_binderfs_device(const struct inode *inode) +{ + return false; +} +static inline struct dentry *binderfs_create_file(struct dentry *dir, + const char *name, + const struct file_operations *fops, + void *data) +{ + return NULL; +} +static inline void binderfs_remove_file(struct dentry *dentry) {} +#endif + +#ifdef CONFIG_ANDROID_BINDERFS +extern int __init init_binderfs(void); +#else +static inline int __init init_binderfs(void) +{ + return 0; +} +#endif + +struct binder_debugfs_entry { + const char *name; + umode_t mode; + const struct file_operations *fops; + void *data; +}; + +extern const struct binder_debugfs_entry binder_debugfs_entries[]; + +#define binder_for_each_debugfs_entry(entry) \ + for ((entry) = binder_debugfs_entries; \ + (entry)->name; \ + (entry)++) + +enum binder_stat_types { + BINDER_STAT_PROC, + BINDER_STAT_THREAD, + BINDER_STAT_NODE, + BINDER_STAT_REF, + BINDER_STAT_DEATH, + BINDER_STAT_TRANSACTION, + BINDER_STAT_TRANSACTION_COMPLETE, + BINDER_STAT_COUNT +}; + +struct binder_stats { + atomic_t br[_IOC_NR(BR_ONEWAY_SPAM_SUSPECT) + 1]; + atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1]; + atomic_t obj_created[BINDER_STAT_COUNT]; + atomic_t obj_deleted[BINDER_STAT_COUNT]; +}; + +/** + * struct binder_work - work enqueued on a worklist + * @entry: node enqueued on list + * @type: type of work to be performed + * + * There are separate work lists for proc, thread, and node (async). + */ +struct binder_work { + struct list_head entry; + + enum binder_work_type { + BINDER_WORK_TRANSACTION = 1, + BINDER_WORK_TRANSACTION_COMPLETE, + BINDER_WORK_TRANSACTION_ONEWAY_SPAM_SUSPECT, + BINDER_WORK_RETURN_ERROR, + BINDER_WORK_NODE, + BINDER_WORK_DEAD_BINDER, + BINDER_WORK_DEAD_BINDER_AND_CLEAR, + BINDER_WORK_CLEAR_DEATH_NOTIFICATION, + } type; +}; + +struct binder_error { + struct binder_work work; + uint32_t cmd; +}; + +/** + * struct binder_node - binder node bookkeeping + * @debug_id: unique ID for debugging + * (invariant after initialized) + * @lock: lock for node fields + * @work: worklist element for node work + * (protected by @proc->inner_lock) + * @rb_node: element for proc->nodes tree + * (protected by @proc->inner_lock) + * @dead_node: element for binder_dead_nodes list + * (protected by binder_dead_nodes_lock) + * @proc: binder_proc that owns this node + * (invariant after initialized) + * @refs: list of references on this node + * (protected by @lock) + * @internal_strong_refs: used to take strong references when + * initiating a transaction + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @local_weak_refs: weak user refs from local process + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @local_strong_refs: strong user refs from local process + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @tmp_refs: temporary kernel refs + * (protected by @proc->inner_lock while @proc + * is valid, and by binder_dead_nodes_lock + * if @proc is NULL. During inc/dec and node release + * it is also protected by @lock to provide safety + * as the node dies and @proc becomes NULL) + * @ptr: userspace pointer for node + * (invariant, no lock needed) + * @cookie: userspace cookie for node + * (invariant, no lock needed) + * @has_strong_ref: userspace notified of strong ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @pending_strong_ref: userspace has acked notification of strong ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @has_weak_ref: userspace notified of weak ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @pending_weak_ref: userspace has acked notification of weak ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @has_async_transaction: async transaction to node in progress + * (protected by @lock) + * @accept_fds: file descriptor operations supported for node + * (invariant after initialized) + * @min_priority: minimum scheduling priority + * (invariant after initialized) + * @txn_security_ctx: require sender's security context + * (invariant after initialized) + * @async_todo: list of async work items + * (protected by @proc->inner_lock) + * + * Bookkeeping structure for binder nodes. + */ +struct binder_node { + int debug_id; + spinlock_t lock; + struct binder_work work; + union { + struct rb_node rb_node; + struct hlist_node dead_node; + }; + struct binder_proc *proc; + struct hlist_head refs; + int internal_strong_refs; + int local_weak_refs; + int local_strong_refs; + int tmp_refs; + binder_uintptr_t ptr; + binder_uintptr_t cookie; + struct { + /* + * bitfield elements protected by + * proc inner_lock + */ + u8 has_strong_ref:1; + u8 pending_strong_ref:1; + u8 has_weak_ref:1; + u8 pending_weak_ref:1; + }; + struct { + /* + * invariant after initialization + */ + u8 accept_fds:1; + u8 txn_security_ctx:1; + u8 min_priority; + }; + bool has_async_transaction; + struct list_head async_todo; +}; + +struct binder_ref_death { + /** + * @work: worklist element for death notifications + * (protected by inner_lock of the proc that + * this ref belongs to) + */ + struct binder_work work; + binder_uintptr_t cookie; +}; + +/** + * struct binder_ref_data - binder_ref counts and id + * @debug_id: unique ID for the ref + * @desc: unique userspace handle for ref + * @strong: strong ref count (debugging only if not locked) + * @weak: weak ref count (debugging only if not locked) + * + * Structure to hold ref count and ref id information. Since + * the actual ref can only be accessed with a lock, this structure + * is used to return information about the ref to callers of + * ref inc/dec functions. + */ +struct binder_ref_data { + int debug_id; + uint32_t desc; + int strong; + int weak; +}; + +/** + * struct binder_ref - struct to track references on nodes + * @data: binder_ref_data containing id, handle, and current refcounts + * @rb_node_desc: node for lookup by @data.desc in proc's rb_tree + * @rb_node_node: node for lookup by @node in proc's rb_tree + * @node_entry: list entry for node->refs list in target node + * (protected by @node->lock) + * @proc: binder_proc containing ref + * @node: binder_node of target node. When cleaning up a + * ref for deletion in binder_cleanup_ref, a non-NULL + * @node indicates the node must be freed + * @death: pointer to death notification (ref_death) if requested + * (protected by @node->lock) + * + * Structure to track references from procA to target node (on procB). This + * structure is unsafe to access without holding @proc->outer_lock. + */ +struct binder_ref { + /* Lookups needed: */ + /* node + proc => ref (transaction) */ + /* desc + proc => ref (transaction, inc/dec ref) */ + /* node => refs + procs (proc exit) */ + struct binder_ref_data data; + struct rb_node rb_node_desc; + struct rb_node rb_node_node; + struct hlist_node node_entry; + struct binder_proc *proc; + struct binder_node *node; + struct binder_ref_death *death; +}; + +/** + * struct binder_proc - binder process bookkeeping + * @proc_node: element for binder_procs list + * @threads: rbtree of binder_threads in this proc + * (protected by @inner_lock) + * @nodes: rbtree of binder nodes associated with + * this proc ordered by node->ptr + * (protected by @inner_lock) + * @refs_by_desc: rbtree of refs ordered by ref->desc + * (protected by @outer_lock) + * @refs_by_node: rbtree of refs ordered by ref->node + * (protected by @outer_lock) + * @waiting_threads: threads currently waiting for proc work + * (protected by @inner_lock) + * @pid PID of group_leader of process + * (invariant after initialized) + * @tsk task_struct for group_leader of process + * (invariant after initialized) + * @cred struct cred associated with the `struct file` + * in binder_open() + * (invariant after initialized) + * @deferred_work_node: element for binder_deferred_list + * (protected by binder_deferred_lock) + * @deferred_work: bitmap of deferred work to perform + * (protected by binder_deferred_lock) + * @outstanding_txns: number of transactions to be transmitted before + * processes in freeze_wait are woken up + * (protected by @inner_lock) + * @is_dead: process is dead and awaiting free + * when outstanding transactions are cleaned up + * (protected by @inner_lock) + * @is_frozen: process is frozen and unable to service + * binder transactions + * (protected by @inner_lock) + * @sync_recv: process received sync transactions since last frozen + * bit 0: received sync transaction after being frozen + * bit 1: new pending sync transaction during freezing + * (protected by @inner_lock) + * @async_recv: process received async transactions since last frozen + * (protected by @inner_lock) + * @freeze_wait: waitqueue of processes waiting for all outstanding + * transactions to be processed + * (protected by @inner_lock) + * @todo: list of work for this process + * (protected by @inner_lock) + * @stats: per-process binder statistics + * (atomics, no lock needed) + * @delivered_death: list of delivered death notification + * (protected by @inner_lock) + * @max_threads: cap on number of binder threads + * (protected by @inner_lock) + * @requested_threads: number of binder threads requested but not + * yet started. In current implementation, can + * only be 0 or 1. + * (protected by @inner_lock) + * @requested_threads_started: number binder threads started + * (protected by @inner_lock) + * @tmp_ref: temporary reference to indicate proc is in use + * (protected by @inner_lock) + * @default_priority: default scheduler priority + * (invariant after initialized) + * @debugfs_entry: debugfs node + * @alloc: binder allocator bookkeeping + * @context: binder_context for this proc + * (invariant after initialized) + * @inner_lock: can nest under outer_lock and/or node lock + * @outer_lock: no nesting under innor or node lock + * Lock order: 1) outer, 2) node, 3) inner + * @binderfs_entry: process-specific binderfs log file + * @oneway_spam_detection_enabled: process enabled oneway spam detection + * or not + * + * Bookkeeping structure for binder processes + */ +struct binder_proc { + struct hlist_node proc_node; + struct rb_root threads; + struct rb_root nodes; + struct rb_root refs_by_desc; + struct rb_root refs_by_node; + struct list_head waiting_threads; + int pid; + struct task_struct *tsk; + const struct cred *cred; + struct hlist_node deferred_work_node; + int deferred_work; + int outstanding_txns; + bool is_dead; + bool is_frozen; + bool sync_recv; + bool async_recv; + wait_queue_head_t freeze_wait; + + struct list_head todo; + struct binder_stats stats; + struct list_head delivered_death; + int max_threads; + int requested_threads; + int requested_threads_started; + int tmp_ref; + long default_priority; + struct dentry *debugfs_entry; + struct binder_alloc alloc; + struct binder_context *context; + spinlock_t inner_lock; + spinlock_t outer_lock; + struct dentry *binderfs_entry; + bool oneway_spam_detection_enabled; +}; + +/** + * struct binder_thread - binder thread bookkeeping + * @proc: binder process for this thread + * (invariant after initialization) + * @rb_node: element for proc->threads rbtree + * (protected by @proc->inner_lock) + * @waiting_thread_node: element for @proc->waiting_threads list + * (protected by @proc->inner_lock) + * @pid: PID for this thread + * (invariant after initialization) + * @looper: bitmap of looping state + * (only accessed by this thread) + * @looper_needs_return: looping thread needs to exit driver + * (no lock needed) + * @transaction_stack: stack of in-progress transactions for this thread + * (protected by @proc->inner_lock) + * @todo: list of work to do for this thread + * (protected by @proc->inner_lock) + * @process_todo: whether work in @todo should be processed + * (protected by @proc->inner_lock) + * @return_error: transaction errors reported by this thread + * (only accessed by this thread) + * @reply_error: transaction errors reported by target thread + * (protected by @proc->inner_lock) + * @ee: extended error information from this thread + * (protected by @proc->inner_lock) + * @wait: wait queue for thread work + * @stats: per-thread statistics + * (atomics, no lock needed) + * @tmp_ref: temporary reference to indicate thread is in use + * (atomic since @proc->inner_lock cannot + * always be acquired) + * @is_dead: thread is dead and awaiting free + * when outstanding transactions are cleaned up + * (protected by @proc->inner_lock) + * + * Bookkeeping structure for binder threads. + */ +struct binder_thread { + struct binder_proc *proc; + struct rb_node rb_node; + struct list_head waiting_thread_node; + int pid; + int looper; /* only modified by this thread */ + bool looper_need_return; /* can be written by other thread */ + struct binder_transaction *transaction_stack; + struct list_head todo; + bool process_todo; + struct binder_error return_error; + struct binder_error reply_error; + struct binder_extended_error ee; + wait_queue_head_t wait; + struct binder_stats stats; + atomic_t tmp_ref; + bool is_dead; +}; + +/** + * struct binder_txn_fd_fixup - transaction fd fixup list element + * @fixup_entry: list entry + * @file: struct file to be associated with new fd + * @offset: offset in buffer data to this fixup + * @target_fd: fd to use by the target to install @file + * + * List element for fd fixups in a transaction. Since file + * descriptors need to be allocated in the context of the + * target process, we pass each fd to be processed in this + * struct. + */ +struct binder_txn_fd_fixup { + struct list_head fixup_entry; + struct file *file; + size_t offset; + int target_fd; +}; + +struct binder_transaction { + int debug_id; + struct binder_work work; + struct binder_thread *from; + struct binder_transaction *from_parent; + struct binder_proc *to_proc; + struct binder_thread *to_thread; + struct binder_transaction *to_parent; + unsigned need_reply:1; + /* unsigned is_dead:1; */ /* not used at the moment */ + + struct binder_buffer *buffer; + unsigned int code; + unsigned int flags; + long priority; + long saved_priority; + kuid_t sender_euid; + struct list_head fd_fixups; + binder_uintptr_t security_ctx; + /** + * @lock: protects @from, @to_proc, and @to_thread + * + * @from, @to_proc, and @to_thread can be set to NULL + * during thread teardown + */ + spinlock_t lock; +}; + +/** + * struct binder_object - union of flat binder object types + * @hdr: generic object header + * @fbo: binder object (nodes and refs) + * @fdo: file descriptor object + * @bbo: binder buffer pointer + * @fdao: file descriptor array + * + * Used for type-independent object copies + */ +struct binder_object { + union { + struct binder_object_header hdr; + struct flat_binder_object fbo; + struct binder_fd_object fdo; + struct binder_buffer_object bbo; + struct binder_fd_array_object fdao; + }; +}; + +#endif /* _LINUX_BINDER_INTERNAL_H */ diff --git a/drivers/android/binder_trace.h b/drivers/android/binder_trace.h new file mode 100644 index 000000000..8cc07e6a4 --- /dev/null +++ b/drivers/android/binder_trace.h @@ -0,0 +1,432 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2012 Google, Inc. + */ + +#undef TRACE_SYSTEM +#define TRACE_SYSTEM binder + +#if !defined(_BINDER_TRACE_H) || defined(TRACE_HEADER_MULTI_READ) +#define _BINDER_TRACE_H + +#include <linux/tracepoint.h> + +struct binder_buffer; +struct binder_node; +struct binder_proc; +struct binder_alloc; +struct binder_ref_data; +struct binder_thread; +struct binder_transaction; + +TRACE_EVENT(binder_ioctl, + TP_PROTO(unsigned int cmd, unsigned long arg), + TP_ARGS(cmd, arg), + + TP_STRUCT__entry( + __field(unsigned int, cmd) + __field(unsigned long, arg) + ), + TP_fast_assign( + __entry->cmd = cmd; + __entry->arg = arg; + ), + TP_printk("cmd=0x%x arg=0x%lx", __entry->cmd, __entry->arg) +); + +DECLARE_EVENT_CLASS(binder_lock_class, + TP_PROTO(const char *tag), + TP_ARGS(tag), + TP_STRUCT__entry( + __field(const char *, tag) + ), + TP_fast_assign( + __entry->tag = tag; + ), + TP_printk("tag=%s", __entry->tag) +); + +#define DEFINE_BINDER_LOCK_EVENT(name) \ +DEFINE_EVENT(binder_lock_class, name, \ + TP_PROTO(const char *func), \ + TP_ARGS(func)) + +DEFINE_BINDER_LOCK_EVENT(binder_lock); +DEFINE_BINDER_LOCK_EVENT(binder_locked); +DEFINE_BINDER_LOCK_EVENT(binder_unlock); + +DECLARE_EVENT_CLASS(binder_function_return_class, + TP_PROTO(int ret), + TP_ARGS(ret), + TP_STRUCT__entry( + __field(int, ret) + ), + TP_fast_assign( + __entry->ret = ret; + ), + TP_printk("ret=%d", __entry->ret) +); + +#define DEFINE_BINDER_FUNCTION_RETURN_EVENT(name) \ +DEFINE_EVENT(binder_function_return_class, name, \ + TP_PROTO(int ret), \ + TP_ARGS(ret)) + +DEFINE_BINDER_FUNCTION_RETURN_EVENT(binder_ioctl_done); +DEFINE_BINDER_FUNCTION_RETURN_EVENT(binder_write_done); +DEFINE_BINDER_FUNCTION_RETURN_EVENT(binder_read_done); + +TRACE_EVENT(binder_wait_for_work, + TP_PROTO(bool proc_work, bool transaction_stack, bool thread_todo), + TP_ARGS(proc_work, transaction_stack, thread_todo), + + TP_STRUCT__entry( + __field(bool, proc_work) + __field(bool, transaction_stack) + __field(bool, thread_todo) + ), + TP_fast_assign( + __entry->proc_work = proc_work; + __entry->transaction_stack = transaction_stack; + __entry->thread_todo = thread_todo; + ), + TP_printk("proc_work=%d transaction_stack=%d thread_todo=%d", + __entry->proc_work, __entry->transaction_stack, + __entry->thread_todo) +); + +TRACE_EVENT(binder_txn_latency_free, + TP_PROTO(struct binder_transaction *t, + int from_proc, int from_thread, + int to_proc, int to_thread), + TP_ARGS(t, from_proc, from_thread, to_proc, to_thread), + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, from_proc) + __field(int, from_thread) + __field(int, to_proc) + __field(int, to_thread) + __field(unsigned int, code) + __field(unsigned int, flags) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->from_proc = from_proc; + __entry->from_thread = from_thread; + __entry->to_proc = to_proc; + __entry->to_thread = to_thread; + __entry->code = t->code; + __entry->flags = t->flags; + ), + TP_printk("transaction=%d from %d:%d to %d:%d flags=0x%x code=0x%x", + __entry->debug_id, __entry->from_proc, __entry->from_thread, + __entry->to_proc, __entry->to_thread, __entry->code, + __entry->flags) +); + +TRACE_EVENT(binder_transaction, + TP_PROTO(bool reply, struct binder_transaction *t, + struct binder_node *target_node), + TP_ARGS(reply, t, target_node), + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, target_node) + __field(int, to_proc) + __field(int, to_thread) + __field(int, reply) + __field(unsigned int, code) + __field(unsigned int, flags) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->target_node = target_node ? target_node->debug_id : 0; + __entry->to_proc = t->to_proc->pid; + __entry->to_thread = t->to_thread ? t->to_thread->pid : 0; + __entry->reply = reply; + __entry->code = t->code; + __entry->flags = t->flags; + ), + TP_printk("transaction=%d dest_node=%d dest_proc=%d dest_thread=%d reply=%d flags=0x%x code=0x%x", + __entry->debug_id, __entry->target_node, + __entry->to_proc, __entry->to_thread, + __entry->reply, __entry->flags, __entry->code) +); + +TRACE_EVENT(binder_transaction_received, + TP_PROTO(struct binder_transaction *t), + TP_ARGS(t), + + TP_STRUCT__entry( + __field(int, debug_id) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + ), + TP_printk("transaction=%d", __entry->debug_id) +); + +TRACE_EVENT(binder_transaction_node_to_ref, + TP_PROTO(struct binder_transaction *t, struct binder_node *node, + struct binder_ref_data *rdata), + TP_ARGS(t, node, rdata), + + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, node_debug_id) + __field(binder_uintptr_t, node_ptr) + __field(int, ref_debug_id) + __field(uint32_t, ref_desc) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->node_debug_id = node->debug_id; + __entry->node_ptr = node->ptr; + __entry->ref_debug_id = rdata->debug_id; + __entry->ref_desc = rdata->desc; + ), + TP_printk("transaction=%d node=%d src_ptr=0x%016llx ==> dest_ref=%d dest_desc=%d", + __entry->debug_id, __entry->node_debug_id, + (u64)__entry->node_ptr, + __entry->ref_debug_id, __entry->ref_desc) +); + +TRACE_EVENT(binder_transaction_ref_to_node, + TP_PROTO(struct binder_transaction *t, struct binder_node *node, + struct binder_ref_data *rdata), + TP_ARGS(t, node, rdata), + + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, ref_debug_id) + __field(uint32_t, ref_desc) + __field(int, node_debug_id) + __field(binder_uintptr_t, node_ptr) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->ref_debug_id = rdata->debug_id; + __entry->ref_desc = rdata->desc; + __entry->node_debug_id = node->debug_id; + __entry->node_ptr = node->ptr; + ), + TP_printk("transaction=%d node=%d src_ref=%d src_desc=%d ==> dest_ptr=0x%016llx", + __entry->debug_id, __entry->node_debug_id, + __entry->ref_debug_id, __entry->ref_desc, + (u64)__entry->node_ptr) +); + +TRACE_EVENT(binder_transaction_ref_to_ref, + TP_PROTO(struct binder_transaction *t, struct binder_node *node, + struct binder_ref_data *src_ref, + struct binder_ref_data *dest_ref), + TP_ARGS(t, node, src_ref, dest_ref), + + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, node_debug_id) + __field(int, src_ref_debug_id) + __field(uint32_t, src_ref_desc) + __field(int, dest_ref_debug_id) + __field(uint32_t, dest_ref_desc) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->node_debug_id = node->debug_id; + __entry->src_ref_debug_id = src_ref->debug_id; + __entry->src_ref_desc = src_ref->desc; + __entry->dest_ref_debug_id = dest_ref->debug_id; + __entry->dest_ref_desc = dest_ref->desc; + ), + TP_printk("transaction=%d node=%d src_ref=%d src_desc=%d ==> dest_ref=%d dest_desc=%d", + __entry->debug_id, __entry->node_debug_id, + __entry->src_ref_debug_id, __entry->src_ref_desc, + __entry->dest_ref_debug_id, __entry->dest_ref_desc) +); + +TRACE_EVENT(binder_transaction_fd_send, + TP_PROTO(struct binder_transaction *t, int fd, size_t offset), + TP_ARGS(t, fd, offset), + + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, fd) + __field(size_t, offset) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->fd = fd; + __entry->offset = offset; + ), + TP_printk("transaction=%d src_fd=%d offset=%zu", + __entry->debug_id, __entry->fd, __entry->offset) +); + +TRACE_EVENT(binder_transaction_fd_recv, + TP_PROTO(struct binder_transaction *t, int fd, size_t offset), + TP_ARGS(t, fd, offset), + + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, fd) + __field(size_t, offset) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->fd = fd; + __entry->offset = offset; + ), + TP_printk("transaction=%d dest_fd=%d offset=%zu", + __entry->debug_id, __entry->fd, __entry->offset) +); + +DECLARE_EVENT_CLASS(binder_buffer_class, + TP_PROTO(struct binder_buffer *buf), + TP_ARGS(buf), + TP_STRUCT__entry( + __field(int, debug_id) + __field(size_t, data_size) + __field(size_t, offsets_size) + __field(size_t, extra_buffers_size) + ), + TP_fast_assign( + __entry->debug_id = buf->debug_id; + __entry->data_size = buf->data_size; + __entry->offsets_size = buf->offsets_size; + __entry->extra_buffers_size = buf->extra_buffers_size; + ), + TP_printk("transaction=%d data_size=%zd offsets_size=%zd extra_buffers_size=%zd", + __entry->debug_id, __entry->data_size, __entry->offsets_size, + __entry->extra_buffers_size) +); + +DEFINE_EVENT(binder_buffer_class, binder_transaction_alloc_buf, + TP_PROTO(struct binder_buffer *buffer), + TP_ARGS(buffer)); + +DEFINE_EVENT(binder_buffer_class, binder_transaction_buffer_release, + TP_PROTO(struct binder_buffer *buffer), + TP_ARGS(buffer)); + +DEFINE_EVENT(binder_buffer_class, binder_transaction_failed_buffer_release, + TP_PROTO(struct binder_buffer *buffer), + TP_ARGS(buffer)); + +DEFINE_EVENT(binder_buffer_class, binder_transaction_update_buffer_release, + TP_PROTO(struct binder_buffer *buffer), + TP_ARGS(buffer)); + +TRACE_EVENT(binder_update_page_range, + TP_PROTO(struct binder_alloc *alloc, bool allocate, + void __user *start, void __user *end), + TP_ARGS(alloc, allocate, start, end), + TP_STRUCT__entry( + __field(int, proc) + __field(bool, allocate) + __field(size_t, offset) + __field(size_t, size) + ), + TP_fast_assign( + __entry->proc = alloc->pid; + __entry->allocate = allocate; + __entry->offset = start - alloc->buffer; + __entry->size = end - start; + ), + TP_printk("proc=%d allocate=%d offset=%zu size=%zu", + __entry->proc, __entry->allocate, + __entry->offset, __entry->size) +); + +DECLARE_EVENT_CLASS(binder_lru_page_class, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index), + TP_STRUCT__entry( + __field(int, proc) + __field(size_t, page_index) + ), + TP_fast_assign( + __entry->proc = alloc->pid; + __entry->page_index = page_index; + ), + TP_printk("proc=%d page_index=%zu", + __entry->proc, __entry->page_index) +); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_lru_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_lru_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_free_lru_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_free_lru_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_page_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_page_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_user_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_user_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_kernel_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_kernel_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +TRACE_EVENT(binder_command, + TP_PROTO(uint32_t cmd), + TP_ARGS(cmd), + TP_STRUCT__entry( + __field(uint32_t, cmd) + ), + TP_fast_assign( + __entry->cmd = cmd; + ), + TP_printk("cmd=0x%x %s", + __entry->cmd, + _IOC_NR(__entry->cmd) < ARRAY_SIZE(binder_command_strings) ? + binder_command_strings[_IOC_NR(__entry->cmd)] : + "unknown") +); + +TRACE_EVENT(binder_return, + TP_PROTO(uint32_t cmd), + TP_ARGS(cmd), + TP_STRUCT__entry( + __field(uint32_t, cmd) + ), + TP_fast_assign( + __entry->cmd = cmd; + ), + TP_printk("cmd=0x%x %s", + __entry->cmd, + _IOC_NR(__entry->cmd) < ARRAY_SIZE(binder_return_strings) ? + binder_return_strings[_IOC_NR(__entry->cmd)] : + "unknown") +); + +#endif /* _BINDER_TRACE_H */ + +#undef TRACE_INCLUDE_PATH +#undef TRACE_INCLUDE_FILE +#define TRACE_INCLUDE_PATH . +#define TRACE_INCLUDE_FILE binder_trace +#include <trace/define_trace.h> diff --git a/drivers/android/binderfs.c b/drivers/android/binderfs.c new file mode 100644 index 000000000..09b2ce7e4 --- /dev/null +++ b/drivers/android/binderfs.c @@ -0,0 +1,828 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/compiler_types.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/fsnotify.h> +#include <linux/gfp.h> +#include <linux/idr.h> +#include <linux/init.h> +#include <linux/ipc_namespace.h> +#include <linux/kdev_t.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/namei.h> +#include <linux/magic.h> +#include <linux/major.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/mount.h> +#include <linux/fs_parser.h> +#include <linux/radix-tree.h> +#include <linux/sched.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/spinlock_types.h> +#include <linux/stddef.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/uaccess.h> +#include <linux/user_namespace.h> +#include <linux/xarray.h> +#include <uapi/asm-generic/errno-base.h> +#include <uapi/linux/android/binder.h> +#include <uapi/linux/android/binderfs.h> + +#include "binder_internal.h" + +#define FIRST_INODE 1 +#define SECOND_INODE 2 +#define INODE_OFFSET 3 +#define BINDERFS_MAX_MINOR (1U << MINORBITS) +/* Ensure that the initial ipc namespace always has devices available. */ +#define BINDERFS_MAX_MINOR_CAPPED (BINDERFS_MAX_MINOR - 4) + +static dev_t binderfs_dev; +static DEFINE_MUTEX(binderfs_minors_mutex); +static DEFINE_IDA(binderfs_minors); + +enum binderfs_param { + Opt_max, + Opt_stats_mode, +}; + +enum binderfs_stats_mode { + binderfs_stats_mode_unset, + binderfs_stats_mode_global, +}; + +struct binder_features { + bool oneway_spam_detection; + bool extended_error; +}; + +static const struct constant_table binderfs_param_stats[] = { + { "global", binderfs_stats_mode_global }, + {} +}; + +static const struct fs_parameter_spec binderfs_fs_parameters[] = { + fsparam_u32("max", Opt_max), + fsparam_enum("stats", Opt_stats_mode, binderfs_param_stats), + {} +}; + +static struct binder_features binder_features = { + .oneway_spam_detection = true, + .extended_error = true, +}; + +static inline struct binderfs_info *BINDERFS_SB(const struct super_block *sb) +{ + return sb->s_fs_info; +} + +bool is_binderfs_device(const struct inode *inode) +{ + if (inode->i_sb->s_magic == BINDERFS_SUPER_MAGIC) + return true; + + return false; +} + +/** + * binderfs_binder_device_create - allocate inode from super block of a + * binderfs mount + * @ref_inode: inode from wich the super block will be taken + * @userp: buffer to copy information about new device for userspace to + * @req: struct binderfs_device as copied from userspace + * + * This function allocates a new binder_device and reserves a new minor + * number for it. + * Minor numbers are limited and tracked globally in binderfs_minors. The + * function will stash a struct binder_device for the specific binder + * device in i_private of the inode. + * It will go on to allocate a new inode from the super block of the + * filesystem mount, stash a struct binder_device in its i_private field + * and attach a dentry to that inode. + * + * Return: 0 on success, negative errno on failure + */ +static int binderfs_binder_device_create(struct inode *ref_inode, + struct binderfs_device __user *userp, + struct binderfs_device *req) +{ + int minor, ret; + struct dentry *dentry, *root; + struct binder_device *device; + char *name = NULL; + size_t name_len; + struct inode *inode = NULL; + struct super_block *sb = ref_inode->i_sb; + struct binderfs_info *info = sb->s_fs_info; +#if defined(CONFIG_IPC_NS) + bool use_reserve = (info->ipc_ns == &init_ipc_ns); +#else + bool use_reserve = true; +#endif + + /* Reserve new minor number for the new device. */ + mutex_lock(&binderfs_minors_mutex); + if (++info->device_count <= info->mount_opts.max) + minor = ida_alloc_max(&binderfs_minors, + use_reserve ? BINDERFS_MAX_MINOR : + BINDERFS_MAX_MINOR_CAPPED, + GFP_KERNEL); + else + minor = -ENOSPC; + if (minor < 0) { + --info->device_count; + mutex_unlock(&binderfs_minors_mutex); + return minor; + } + mutex_unlock(&binderfs_minors_mutex); + + ret = -ENOMEM; + device = kzalloc(sizeof(*device), GFP_KERNEL); + if (!device) + goto err; + + inode = new_inode(sb); + if (!inode) + goto err; + + inode->i_ino = minor + INODE_OFFSET; + inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); + init_special_inode(inode, S_IFCHR | 0600, + MKDEV(MAJOR(binderfs_dev), minor)); + inode->i_fop = &binder_fops; + inode->i_uid = info->root_uid; + inode->i_gid = info->root_gid; + + req->name[BINDERFS_MAX_NAME] = '\0'; /* NUL-terminate */ + name_len = strlen(req->name); + /* Make sure to include terminating NUL byte */ + name = kmemdup(req->name, name_len + 1, GFP_KERNEL); + if (!name) + goto err; + + refcount_set(&device->ref, 1); + device->binderfs_inode = inode; + device->context.binder_context_mgr_uid = INVALID_UID; + device->context.name = name; + device->miscdev.name = name; + device->miscdev.minor = minor; + mutex_init(&device->context.context_mgr_node_lock); + + req->major = MAJOR(binderfs_dev); + req->minor = minor; + + if (userp && copy_to_user(userp, req, sizeof(*req))) { + ret = -EFAULT; + goto err; + } + + root = sb->s_root; + inode_lock(d_inode(root)); + + /* look it up */ + dentry = lookup_one_len(name, root, name_len); + if (IS_ERR(dentry)) { + inode_unlock(d_inode(root)); + ret = PTR_ERR(dentry); + goto err; + } + + if (d_really_is_positive(dentry)) { + /* already exists */ + dput(dentry); + inode_unlock(d_inode(root)); + ret = -EEXIST; + goto err; + } + + inode->i_private = device; + d_instantiate(dentry, inode); + fsnotify_create(root->d_inode, dentry); + inode_unlock(d_inode(root)); + + return 0; + +err: + kfree(name); + kfree(device); + mutex_lock(&binderfs_minors_mutex); + --info->device_count; + ida_free(&binderfs_minors, minor); + mutex_unlock(&binderfs_minors_mutex); + iput(inode); + + return ret; +} + +/** + * binderfs_ctl_ioctl - handle binder device node allocation requests + * + * The request handler for the binder-control device. All requests operate on + * the binderfs mount the binder-control device resides in: + * - BINDER_CTL_ADD + * Allocate a new binder device. + * + * Return: 0 on success, negative errno on failure + */ +static long binder_ctl_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int ret = -EINVAL; + struct inode *inode = file_inode(file); + struct binderfs_device __user *device = (struct binderfs_device __user *)arg; + struct binderfs_device device_req; + + switch (cmd) { + case BINDER_CTL_ADD: + ret = copy_from_user(&device_req, device, sizeof(device_req)); + if (ret) { + ret = -EFAULT; + break; + } + + ret = binderfs_binder_device_create(inode, device, &device_req); + break; + default: + break; + } + + return ret; +} + +static void binderfs_evict_inode(struct inode *inode) +{ + struct binder_device *device = inode->i_private; + struct binderfs_info *info = BINDERFS_SB(inode->i_sb); + + clear_inode(inode); + + if (!S_ISCHR(inode->i_mode) || !device) + return; + + mutex_lock(&binderfs_minors_mutex); + --info->device_count; + ida_free(&binderfs_minors, device->miscdev.minor); + mutex_unlock(&binderfs_minors_mutex); + + if (refcount_dec_and_test(&device->ref)) { + kfree(device->context.name); + kfree(device); + } +} + +static int binderfs_fs_context_parse_param(struct fs_context *fc, + struct fs_parameter *param) +{ + int opt; + struct binderfs_mount_opts *ctx = fc->fs_private; + struct fs_parse_result result; + + opt = fs_parse(fc, binderfs_fs_parameters, param, &result); + if (opt < 0) + return opt; + + switch (opt) { + case Opt_max: + if (result.uint_32 > BINDERFS_MAX_MINOR) + return invalfc(fc, "Bad value for '%s'", param->key); + + ctx->max = result.uint_32; + break; + case Opt_stats_mode: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ctx->stats_mode = result.uint_32; + break; + default: + return invalfc(fc, "Unsupported parameter '%s'", param->key); + } + + return 0; +} + +static int binderfs_fs_context_reconfigure(struct fs_context *fc) +{ + struct binderfs_mount_opts *ctx = fc->fs_private; + struct binderfs_info *info = BINDERFS_SB(fc->root->d_sb); + + if (info->mount_opts.stats_mode != ctx->stats_mode) + return invalfc(fc, "Binderfs stats mode cannot be changed during a remount"); + + info->mount_opts.stats_mode = ctx->stats_mode; + info->mount_opts.max = ctx->max; + return 0; +} + +static int binderfs_show_options(struct seq_file *seq, struct dentry *root) +{ + struct binderfs_info *info = BINDERFS_SB(root->d_sb); + + if (info->mount_opts.max <= BINDERFS_MAX_MINOR) + seq_printf(seq, ",max=%d", info->mount_opts.max); + + switch (info->mount_opts.stats_mode) { + case binderfs_stats_mode_unset: + break; + case binderfs_stats_mode_global: + seq_printf(seq, ",stats=global"); + break; + } + + return 0; +} + +static const struct super_operations binderfs_super_ops = { + .evict_inode = binderfs_evict_inode, + .show_options = binderfs_show_options, + .statfs = simple_statfs, +}; + +static inline bool is_binderfs_control_device(const struct dentry *dentry) +{ + struct binderfs_info *info = dentry->d_sb->s_fs_info; + + return info->control_dentry == dentry; +} + +static int binderfs_rename(struct user_namespace *mnt_userns, + struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags) +{ + if (is_binderfs_control_device(old_dentry) || + is_binderfs_control_device(new_dentry)) + return -EPERM; + + return simple_rename(&init_user_ns, old_dir, old_dentry, new_dir, + new_dentry, flags); +} + +static int binderfs_unlink(struct inode *dir, struct dentry *dentry) +{ + if (is_binderfs_control_device(dentry)) + return -EPERM; + + return simple_unlink(dir, dentry); +} + +static const struct file_operations binder_ctl_fops = { + .owner = THIS_MODULE, + .open = nonseekable_open, + .unlocked_ioctl = binder_ctl_ioctl, + .compat_ioctl = binder_ctl_ioctl, + .llseek = noop_llseek, +}; + +/** + * binderfs_binder_ctl_create - create a new binder-control device + * @sb: super block of the binderfs mount + * + * This function creates a new binder-control device node in the binderfs mount + * referred to by @sb. + * + * Return: 0 on success, negative errno on failure + */ +static int binderfs_binder_ctl_create(struct super_block *sb) +{ + int minor, ret; + struct dentry *dentry; + struct binder_device *device; + struct inode *inode = NULL; + struct dentry *root = sb->s_root; + struct binderfs_info *info = sb->s_fs_info; +#if defined(CONFIG_IPC_NS) + bool use_reserve = (info->ipc_ns == &init_ipc_ns); +#else + bool use_reserve = true; +#endif + + device = kzalloc(sizeof(*device), GFP_KERNEL); + if (!device) + return -ENOMEM; + + /* If we have already created a binder-control node, return. */ + if (info->control_dentry) { + ret = 0; + goto out; + } + + ret = -ENOMEM; + inode = new_inode(sb); + if (!inode) + goto out; + + /* Reserve a new minor number for the new device. */ + mutex_lock(&binderfs_minors_mutex); + minor = ida_alloc_max(&binderfs_minors, + use_reserve ? BINDERFS_MAX_MINOR : + BINDERFS_MAX_MINOR_CAPPED, + GFP_KERNEL); + mutex_unlock(&binderfs_minors_mutex); + if (minor < 0) { + ret = minor; + goto out; + } + + inode->i_ino = SECOND_INODE; + inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); + init_special_inode(inode, S_IFCHR | 0600, + MKDEV(MAJOR(binderfs_dev), minor)); + inode->i_fop = &binder_ctl_fops; + inode->i_uid = info->root_uid; + inode->i_gid = info->root_gid; + + refcount_set(&device->ref, 1); + device->binderfs_inode = inode; + device->miscdev.minor = minor; + + dentry = d_alloc_name(root, "binder-control"); + if (!dentry) + goto out; + + inode->i_private = device; + info->control_dentry = dentry; + d_add(dentry, inode); + + return 0; + +out: + kfree(device); + iput(inode); + + return ret; +} + +static const struct inode_operations binderfs_dir_inode_operations = { + .lookup = simple_lookup, + .rename = binderfs_rename, + .unlink = binderfs_unlink, +}; + +static struct inode *binderfs_make_inode(struct super_block *sb, int mode) +{ + struct inode *ret; + + ret = new_inode(sb); + if (ret) { + ret->i_ino = iunique(sb, BINDERFS_MAX_MINOR + INODE_OFFSET); + ret->i_mode = mode; + ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret); + } + return ret; +} + +static struct dentry *binderfs_create_dentry(struct dentry *parent, + const char *name) +{ + struct dentry *dentry; + + dentry = lookup_one_len(name, parent, strlen(name)); + if (IS_ERR(dentry)) + return dentry; + + /* Return error if the file/dir already exists. */ + if (d_really_is_positive(dentry)) { + dput(dentry); + return ERR_PTR(-EEXIST); + } + + return dentry; +} + +void binderfs_remove_file(struct dentry *dentry) +{ + struct inode *parent_inode; + + parent_inode = d_inode(dentry->d_parent); + inode_lock(parent_inode); + if (simple_positive(dentry)) { + dget(dentry); + simple_unlink(parent_inode, dentry); + d_delete(dentry); + dput(dentry); + } + inode_unlock(parent_inode); +} + +struct dentry *binderfs_create_file(struct dentry *parent, const char *name, + const struct file_operations *fops, + void *data) +{ + struct dentry *dentry; + struct inode *new_inode, *parent_inode; + struct super_block *sb; + + parent_inode = d_inode(parent); + inode_lock(parent_inode); + + dentry = binderfs_create_dentry(parent, name); + if (IS_ERR(dentry)) + goto out; + + sb = parent_inode->i_sb; + new_inode = binderfs_make_inode(sb, S_IFREG | 0444); + if (!new_inode) { + dput(dentry); + dentry = ERR_PTR(-ENOMEM); + goto out; + } + + new_inode->i_fop = fops; + new_inode->i_private = data; + d_instantiate(dentry, new_inode); + fsnotify_create(parent_inode, dentry); + +out: + inode_unlock(parent_inode); + return dentry; +} + +static struct dentry *binderfs_create_dir(struct dentry *parent, + const char *name) +{ + struct dentry *dentry; + struct inode *new_inode, *parent_inode; + struct super_block *sb; + + parent_inode = d_inode(parent); + inode_lock(parent_inode); + + dentry = binderfs_create_dentry(parent, name); + if (IS_ERR(dentry)) + goto out; + + sb = parent_inode->i_sb; + new_inode = binderfs_make_inode(sb, S_IFDIR | 0755); + if (!new_inode) { + dput(dentry); + dentry = ERR_PTR(-ENOMEM); + goto out; + } + + new_inode->i_fop = &simple_dir_operations; + new_inode->i_op = &simple_dir_inode_operations; + + set_nlink(new_inode, 2); + d_instantiate(dentry, new_inode); + inc_nlink(parent_inode); + fsnotify_mkdir(parent_inode, dentry); + +out: + inode_unlock(parent_inode); + return dentry; +} + +static int binder_features_show(struct seq_file *m, void *unused) +{ + bool *feature = m->private; + + seq_printf(m, "%d\n", *feature); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(binder_features); + +static int init_binder_features(struct super_block *sb) +{ + struct dentry *dentry, *dir; + + dir = binderfs_create_dir(sb->s_root, "features"); + if (IS_ERR(dir)) + return PTR_ERR(dir); + + dentry = binderfs_create_file(dir, "oneway_spam_detection", + &binder_features_fops, + &binder_features.oneway_spam_detection); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + + dentry = binderfs_create_file(dir, "extended_error", + &binder_features_fops, + &binder_features.extended_error); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + + return 0; +} + +static int init_binder_logs(struct super_block *sb) +{ + struct dentry *binder_logs_root_dir, *dentry, *proc_log_dir; + const struct binder_debugfs_entry *db_entry; + struct binderfs_info *info; + int ret = 0; + + binder_logs_root_dir = binderfs_create_dir(sb->s_root, + "binder_logs"); + if (IS_ERR(binder_logs_root_dir)) { + ret = PTR_ERR(binder_logs_root_dir); + goto out; + } + + binder_for_each_debugfs_entry(db_entry) { + dentry = binderfs_create_file(binder_logs_root_dir, + db_entry->name, + db_entry->fops, + db_entry->data); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out; + } + } + + proc_log_dir = binderfs_create_dir(binder_logs_root_dir, "proc"); + if (IS_ERR(proc_log_dir)) { + ret = PTR_ERR(proc_log_dir); + goto out; + } + info = sb->s_fs_info; + info->proc_log_dir = proc_log_dir; + +out: + return ret; +} + +static int binderfs_fill_super(struct super_block *sb, struct fs_context *fc) +{ + int ret; + struct binderfs_info *info; + struct binderfs_mount_opts *ctx = fc->fs_private; + struct inode *inode = NULL; + struct binderfs_device device_info = {}; + const char *name; + size_t len; + + sb->s_blocksize = PAGE_SIZE; + sb->s_blocksize_bits = PAGE_SHIFT; + + /* + * The binderfs filesystem can be mounted by userns root in a + * non-initial userns. By default such mounts have the SB_I_NODEV flag + * set in s_iflags to prevent security issues where userns root can + * just create random device nodes via mknod() since it owns the + * filesystem mount. But binderfs does not allow to create any files + * including devices nodes. The only way to create binder devices nodes + * is through the binder-control device which userns root is explicitly + * allowed to do. So removing the SB_I_NODEV flag from s_iflags is both + * necessary and safe. + */ + sb->s_iflags &= ~SB_I_NODEV; + sb->s_iflags |= SB_I_NOEXEC; + sb->s_magic = BINDERFS_SUPER_MAGIC; + sb->s_op = &binderfs_super_ops; + sb->s_time_gran = 1; + + sb->s_fs_info = kzalloc(sizeof(struct binderfs_info), GFP_KERNEL); + if (!sb->s_fs_info) + return -ENOMEM; + info = sb->s_fs_info; + + info->ipc_ns = get_ipc_ns(current->nsproxy->ipc_ns); + + info->root_gid = make_kgid(sb->s_user_ns, 0); + if (!gid_valid(info->root_gid)) + info->root_gid = GLOBAL_ROOT_GID; + info->root_uid = make_kuid(sb->s_user_ns, 0); + if (!uid_valid(info->root_uid)) + info->root_uid = GLOBAL_ROOT_UID; + info->mount_opts.max = ctx->max; + info->mount_opts.stats_mode = ctx->stats_mode; + + inode = new_inode(sb); + if (!inode) + return -ENOMEM; + + inode->i_ino = FIRST_INODE; + inode->i_fop = &simple_dir_operations; + inode->i_mode = S_IFDIR | 0755; + inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); + inode->i_op = &binderfs_dir_inode_operations; + set_nlink(inode, 2); + + sb->s_root = d_make_root(inode); + if (!sb->s_root) + return -ENOMEM; + + ret = binderfs_binder_ctl_create(sb); + if (ret) + return ret; + + name = binder_devices_param; + for (len = strcspn(name, ","); len > 0; len = strcspn(name, ",")) { + strscpy(device_info.name, name, len + 1); + ret = binderfs_binder_device_create(inode, NULL, &device_info); + if (ret) + return ret; + name += len; + if (*name == ',') + name++; + } + + ret = init_binder_features(sb); + if (ret) + return ret; + + if (info->mount_opts.stats_mode == binderfs_stats_mode_global) + return init_binder_logs(sb); + + return 0; +} + +static int binderfs_fs_context_get_tree(struct fs_context *fc) +{ + return get_tree_nodev(fc, binderfs_fill_super); +} + +static void binderfs_fs_context_free(struct fs_context *fc) +{ + struct binderfs_mount_opts *ctx = fc->fs_private; + + kfree(ctx); +} + +static const struct fs_context_operations binderfs_fs_context_ops = { + .free = binderfs_fs_context_free, + .get_tree = binderfs_fs_context_get_tree, + .parse_param = binderfs_fs_context_parse_param, + .reconfigure = binderfs_fs_context_reconfigure, +}; + +static int binderfs_init_fs_context(struct fs_context *fc) +{ + struct binderfs_mount_opts *ctx; + + ctx = kzalloc(sizeof(struct binderfs_mount_opts), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->max = BINDERFS_MAX_MINOR; + ctx->stats_mode = binderfs_stats_mode_unset; + + fc->fs_private = ctx; + fc->ops = &binderfs_fs_context_ops; + + return 0; +} + +static void binderfs_kill_super(struct super_block *sb) +{ + struct binderfs_info *info = sb->s_fs_info; + + /* + * During inode eviction struct binderfs_info is needed. + * So first wipe the super_block then free struct binderfs_info. + */ + kill_litter_super(sb); + + if (info && info->ipc_ns) + put_ipc_ns(info->ipc_ns); + + kfree(info); +} + +static struct file_system_type binder_fs_type = { + .name = "binder", + .init_fs_context = binderfs_init_fs_context, + .parameters = binderfs_fs_parameters, + .kill_sb = binderfs_kill_super, + .fs_flags = FS_USERNS_MOUNT, +}; + +int __init init_binderfs(void) +{ + int ret; + const char *name; + size_t len; + + /* Verify that the default binderfs device names are valid. */ + name = binder_devices_param; + for (len = strcspn(name, ","); len > 0; len = strcspn(name, ",")) { + if (len > BINDERFS_MAX_NAME) + return -E2BIG; + name += len; + if (*name == ',') + name++; + } + + /* Allocate new major number for binderfs. */ + ret = alloc_chrdev_region(&binderfs_dev, 0, BINDERFS_MAX_MINOR, + "binder"); + if (ret) + return ret; + + ret = register_filesystem(&binder_fs_type); + if (ret) { + unregister_chrdev_region(binderfs_dev, BINDERFS_MAX_MINOR); + return ret; + } + + return ret; +} |