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-rw-r--r--kernel/trace/bpf_trace.c2251
1 files changed, 2251 insertions, 0 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
new file mode 100644
index 000000000..71e0c1bc9
--- /dev/null
+++ b/kernel/trace/bpf_trace.c
@@ -0,0 +1,2251 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2016 Facebook
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/bpf.h>
+#include <linux/bpf_perf_event.h>
+#include <linux/btf.h>
+#include <linux/filter.h>
+#include <linux/uaccess.h>
+#include <linux/ctype.h>
+#include <linux/kprobes.h>
+#include <linux/spinlock.h>
+#include <linux/syscalls.h>
+#include <linux/error-injection.h>
+#include <linux/btf_ids.h>
+
+#include <uapi/linux/bpf.h>
+#include <uapi/linux/btf.h>
+
+#include <asm/tlb.h>
+
+#include "trace_probe.h"
+#include "trace.h"
+
+#define CREATE_TRACE_POINTS
+#include "bpf_trace.h"
+
+#define bpf_event_rcu_dereference(p) \
+ rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
+
+#ifdef CONFIG_MODULES
+struct bpf_trace_module {
+ struct module *module;
+ struct list_head list;
+};
+
+static LIST_HEAD(bpf_trace_modules);
+static DEFINE_MUTEX(bpf_module_mutex);
+
+static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
+{
+ struct bpf_raw_event_map *btp, *ret = NULL;
+ struct bpf_trace_module *btm;
+ unsigned int i;
+
+ mutex_lock(&bpf_module_mutex);
+ list_for_each_entry(btm, &bpf_trace_modules, list) {
+ for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
+ btp = &btm->module->bpf_raw_events[i];
+ if (!strcmp(btp->tp->name, name)) {
+ if (try_module_get(btm->module))
+ ret = btp;
+ goto out;
+ }
+ }
+ }
+out:
+ mutex_unlock(&bpf_module_mutex);
+ return ret;
+}
+#else
+static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
+{
+ return NULL;
+}
+#endif /* CONFIG_MODULES */
+
+u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
+u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
+
+static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
+ u64 flags, const struct btf **btf,
+ s32 *btf_id);
+
+/**
+ * trace_call_bpf - invoke BPF program
+ * @call: tracepoint event
+ * @ctx: opaque context pointer
+ *
+ * kprobe handlers execute BPF programs via this helper.
+ * Can be used from static tracepoints in the future.
+ *
+ * Return: BPF programs always return an integer which is interpreted by
+ * kprobe handler as:
+ * 0 - return from kprobe (event is filtered out)
+ * 1 - store kprobe event into ring buffer
+ * Other values are reserved and currently alias to 1
+ */
+unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
+{
+ unsigned int ret;
+
+ cant_sleep();
+
+ if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
+ /*
+ * since some bpf program is already running on this cpu,
+ * don't call into another bpf program (same or different)
+ * and don't send kprobe event into ring-buffer,
+ * so return zero here
+ */
+ ret = 0;
+ goto out;
+ }
+
+ /*
+ * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
+ * to all call sites, we did a bpf_prog_array_valid() there to check
+ * whether call->prog_array is empty or not, which is
+ * a heurisitc to speed up execution.
+ *
+ * If bpf_prog_array_valid() fetched prog_array was
+ * non-NULL, we go into trace_call_bpf() and do the actual
+ * proper rcu_dereference() under RCU lock.
+ * If it turns out that prog_array is NULL then, we bail out.
+ * For the opposite, if the bpf_prog_array_valid() fetched pointer
+ * was NULL, you'll skip the prog_array with the risk of missing
+ * out of events when it was updated in between this and the
+ * rcu_dereference() which is accepted risk.
+ */
+ ret = BPF_PROG_RUN_ARRAY_CHECK(call->prog_array, ctx, BPF_PROG_RUN);
+
+ out:
+ __this_cpu_dec(bpf_prog_active);
+
+ return ret;
+}
+
+#ifdef CONFIG_BPF_KPROBE_OVERRIDE
+BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
+{
+ regs_set_return_value(regs, rc);
+ override_function_with_return(regs);
+ return 0;
+}
+
+static const struct bpf_func_proto bpf_override_return_proto = {
+ .func = bpf_override_return,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+};
+#endif
+
+static __always_inline int
+bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
+{
+ int ret;
+
+ ret = copy_from_user_nofault(dst, unsafe_ptr, size);
+ if (unlikely(ret < 0))
+ memset(dst, 0, size);
+ return ret;
+}
+
+BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
+ const void __user *, unsafe_ptr)
+{
+ return bpf_probe_read_user_common(dst, size, unsafe_ptr);
+}
+
+const struct bpf_func_proto bpf_probe_read_user_proto = {
+ .func = bpf_probe_read_user,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg3_type = ARG_ANYTHING,
+};
+
+static __always_inline int
+bpf_probe_read_user_str_common(void *dst, u32 size,
+ const void __user *unsafe_ptr)
+{
+ int ret;
+
+ /*
+ * NB: We rely on strncpy_from_user() not copying junk past the NUL
+ * terminator into `dst`.
+ *
+ * strncpy_from_user() does long-sized strides in the fast path. If the
+ * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`,
+ * then there could be junk after the NUL in `dst`. If user takes `dst`
+ * and keys a hash map with it, then semantically identical strings can
+ * occupy multiple entries in the map.
+ */
+ ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
+ if (unlikely(ret < 0))
+ memset(dst, 0, size);
+ return ret;
+}
+
+BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
+ const void __user *, unsafe_ptr)
+{
+ return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
+}
+
+const struct bpf_func_proto bpf_probe_read_user_str_proto = {
+ .func = bpf_probe_read_user_str,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg3_type = ARG_ANYTHING,
+};
+
+static __always_inline int
+bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
+{
+ int ret;
+
+ ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
+ if (unlikely(ret < 0))
+ memset(dst, 0, size);
+ return ret;
+}
+
+BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
+ const void *, unsafe_ptr)
+{
+ return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
+}
+
+const struct bpf_func_proto bpf_probe_read_kernel_proto = {
+ .func = bpf_probe_read_kernel,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg3_type = ARG_ANYTHING,
+};
+
+static __always_inline int
+bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
+{
+ int ret;
+
+ /*
+ * The strncpy_from_kernel_nofault() call will likely not fill the
+ * entire buffer, but that's okay in this circumstance as we're probing
+ * arbitrary memory anyway similar to bpf_probe_read_*() and might
+ * as well probe the stack. Thus, memory is explicitly cleared
+ * only in error case, so that improper users ignoring return
+ * code altogether don't copy garbage; otherwise length of string
+ * is returned that can be used for bpf_perf_event_output() et al.
+ */
+ ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
+ if (unlikely(ret < 0))
+ memset(dst, 0, size);
+ return ret;
+}
+
+BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
+ const void *, unsafe_ptr)
+{
+ return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
+}
+
+const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
+ .func = bpf_probe_read_kernel_str,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg3_type = ARG_ANYTHING,
+};
+
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
+ const void *, unsafe_ptr)
+{
+ if ((unsigned long)unsafe_ptr < TASK_SIZE) {
+ return bpf_probe_read_user_common(dst, size,
+ (__force void __user *)unsafe_ptr);
+ }
+ return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
+}
+
+static const struct bpf_func_proto bpf_probe_read_compat_proto = {
+ .func = bpf_probe_read_compat,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg3_type = ARG_ANYTHING,
+};
+
+BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size,
+ const void *, unsafe_ptr)
+{
+ if ((unsigned long)unsafe_ptr < TASK_SIZE) {
+ return bpf_probe_read_user_str_common(dst, size,
+ (__force void __user *)unsafe_ptr);
+ }
+ return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
+}
+
+static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
+ .func = bpf_probe_read_compat_str,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg3_type = ARG_ANYTHING,
+};
+#endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
+
+BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
+ u32, size)
+{
+ /*
+ * Ensure we're in user context which is safe for the helper to
+ * run. This helper has no business in a kthread.
+ *
+ * access_ok() should prevent writing to non-user memory, but in
+ * some situations (nommu, temporary switch, etc) access_ok() does
+ * not provide enough validation, hence the check on KERNEL_DS.
+ *
+ * nmi_uaccess_okay() ensures the probe is not run in an interim
+ * state, when the task or mm are switched. This is specifically
+ * required to prevent the use of temporary mm.
+ */
+
+ if (unlikely(in_interrupt() ||
+ current->flags & (PF_KTHREAD | PF_EXITING)))
+ return -EPERM;
+ if (unlikely(uaccess_kernel()))
+ return -EPERM;
+ if (unlikely(!nmi_uaccess_okay()))
+ return -EPERM;
+
+ return copy_to_user_nofault(unsafe_ptr, src, size);
+}
+
+static const struct bpf_func_proto bpf_probe_write_user_proto = {
+ .func = bpf_probe_write_user,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_ANYTHING,
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE,
+};
+
+static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return NULL;
+
+ pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
+ current->comm, task_pid_nr(current));
+
+ return &bpf_probe_write_user_proto;
+}
+
+static void bpf_trace_copy_string(char *buf, void *unsafe_ptr, char fmt_ptype,
+ size_t bufsz)
+{
+ void __user *user_ptr = (__force void __user *)unsafe_ptr;
+
+ buf[0] = 0;
+
+ switch (fmt_ptype) {
+ case 's':
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+ if ((unsigned long)unsafe_ptr < TASK_SIZE) {
+ strncpy_from_user_nofault(buf, user_ptr, bufsz);
+ break;
+ }
+ fallthrough;
+#endif
+ case 'k':
+ strncpy_from_kernel_nofault(buf, unsafe_ptr, bufsz);
+ break;
+ case 'u':
+ strncpy_from_user_nofault(buf, user_ptr, bufsz);
+ break;
+ }
+}
+
+static DEFINE_RAW_SPINLOCK(trace_printk_lock);
+
+#define BPF_TRACE_PRINTK_SIZE 1024
+
+static __printf(1, 0) int bpf_do_trace_printk(const char *fmt, ...)
+{
+ static char buf[BPF_TRACE_PRINTK_SIZE];
+ unsigned long flags;
+ va_list ap;
+ int ret;
+
+ raw_spin_lock_irqsave(&trace_printk_lock, flags);
+ va_start(ap, fmt);
+ ret = vsnprintf(buf, sizeof(buf), fmt, ap);
+ va_end(ap);
+ /* vsnprintf() will not append null for zero-length strings */
+ if (ret == 0)
+ buf[0] = '\0';
+ trace_bpf_trace_printk(buf);
+ raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
+
+ return ret;
+}
+
+/*
+ * Only limited trace_printk() conversion specifiers allowed:
+ * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %pB %pks %pus %s
+ */
+BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
+ u64, arg2, u64, arg3)
+{
+ int i, mod[3] = {}, fmt_cnt = 0;
+ char buf[64], fmt_ptype;
+ void *unsafe_ptr = NULL;
+ bool str_seen = false;
+
+ /*
+ * bpf_check()->check_func_arg()->check_stack_boundary()
+ * guarantees that fmt points to bpf program stack,
+ * fmt_size bytes of it were initialized and fmt_size > 0
+ */
+ if (fmt[--fmt_size] != 0)
+ return -EINVAL;
+
+ /* check format string for allowed specifiers */
+ for (i = 0; i < fmt_size; i++) {
+ if ((!isprint(fmt[i]) && !isspace(fmt[i])) || !isascii(fmt[i]))
+ return -EINVAL;
+
+ if (fmt[i] != '%')
+ continue;
+
+ if (fmt_cnt >= 3)
+ return -EINVAL;
+
+ /* fmt[i] != 0 && fmt[last] == 0, so we can access fmt[i + 1] */
+ i++;
+ if (fmt[i] == 'l') {
+ mod[fmt_cnt]++;
+ i++;
+ } else if (fmt[i] == 'p') {
+ mod[fmt_cnt]++;
+ if ((fmt[i + 1] == 'k' ||
+ fmt[i + 1] == 'u') &&
+ fmt[i + 2] == 's') {
+ fmt_ptype = fmt[i + 1];
+ i += 2;
+ goto fmt_str;
+ }
+
+ if (fmt[i + 1] == 'B') {
+ i++;
+ goto fmt_next;
+ }
+
+ /* disallow any further format extensions */
+ if (fmt[i + 1] != 0 &&
+ !isspace(fmt[i + 1]) &&
+ !ispunct(fmt[i + 1]))
+ return -EINVAL;
+
+ goto fmt_next;
+ } else if (fmt[i] == 's') {
+ mod[fmt_cnt]++;
+ fmt_ptype = fmt[i];
+fmt_str:
+ if (str_seen)
+ /* allow only one '%s' per fmt string */
+ return -EINVAL;
+ str_seen = true;
+
+ if (fmt[i + 1] != 0 &&
+ !isspace(fmt[i + 1]) &&
+ !ispunct(fmt[i + 1]))
+ return -EINVAL;
+
+ switch (fmt_cnt) {
+ case 0:
+ unsafe_ptr = (void *)(long)arg1;
+ arg1 = (long)buf;
+ break;
+ case 1:
+ unsafe_ptr = (void *)(long)arg2;
+ arg2 = (long)buf;
+ break;
+ case 2:
+ unsafe_ptr = (void *)(long)arg3;
+ arg3 = (long)buf;
+ break;
+ }
+
+ bpf_trace_copy_string(buf, unsafe_ptr, fmt_ptype,
+ sizeof(buf));
+ goto fmt_next;
+ }
+
+ if (fmt[i] == 'l') {
+ mod[fmt_cnt]++;
+ i++;
+ }
+
+ if (fmt[i] != 'i' && fmt[i] != 'd' &&
+ fmt[i] != 'u' && fmt[i] != 'x')
+ return -EINVAL;
+fmt_next:
+ fmt_cnt++;
+ }
+
+/* Horrid workaround for getting va_list handling working with different
+ * argument type combinations generically for 32 and 64 bit archs.
+ */
+#define __BPF_TP_EMIT() __BPF_ARG3_TP()
+#define __BPF_TP(...) \
+ bpf_do_trace_printk(fmt, ##__VA_ARGS__)
+
+#define __BPF_ARG1_TP(...) \
+ ((mod[0] == 2 || (mod[0] == 1 && __BITS_PER_LONG == 64)) \
+ ? __BPF_TP(arg1, ##__VA_ARGS__) \
+ : ((mod[0] == 1 || (mod[0] == 0 && __BITS_PER_LONG == 32)) \
+ ? __BPF_TP((long)arg1, ##__VA_ARGS__) \
+ : __BPF_TP((u32)arg1, ##__VA_ARGS__)))
+
+#define __BPF_ARG2_TP(...) \
+ ((mod[1] == 2 || (mod[1] == 1 && __BITS_PER_LONG == 64)) \
+ ? __BPF_ARG1_TP(arg2, ##__VA_ARGS__) \
+ : ((mod[1] == 1 || (mod[1] == 0 && __BITS_PER_LONG == 32)) \
+ ? __BPF_ARG1_TP((long)arg2, ##__VA_ARGS__) \
+ : __BPF_ARG1_TP((u32)arg2, ##__VA_ARGS__)))
+
+#define __BPF_ARG3_TP(...) \
+ ((mod[2] == 2 || (mod[2] == 1 && __BITS_PER_LONG == 64)) \
+ ? __BPF_ARG2_TP(arg3, ##__VA_ARGS__) \
+ : ((mod[2] == 1 || (mod[2] == 0 && __BITS_PER_LONG == 32)) \
+ ? __BPF_ARG2_TP((long)arg3, ##__VA_ARGS__) \
+ : __BPF_ARG2_TP((u32)arg3, ##__VA_ARGS__)))
+
+ return __BPF_TP_EMIT();
+}
+
+static const struct bpf_func_proto bpf_trace_printk_proto = {
+ .func = bpf_trace_printk,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_MEM,
+ .arg2_type = ARG_CONST_SIZE,
+};
+
+const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
+{
+ /*
+ * This program might be calling bpf_trace_printk,
+ * so enable the associated bpf_trace/bpf_trace_printk event.
+ * Repeat this each time as it is possible a user has
+ * disabled bpf_trace_printk events. By loading a program
+ * calling bpf_trace_printk() however the user has expressed
+ * the intent to see such events.
+ */
+ if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1))
+ pr_warn_ratelimited("could not enable bpf_trace_printk events");
+
+ return &bpf_trace_printk_proto;
+}
+
+#define MAX_SEQ_PRINTF_VARARGS 12
+#define MAX_SEQ_PRINTF_MAX_MEMCPY 6
+#define MAX_SEQ_PRINTF_STR_LEN 128
+
+struct bpf_seq_printf_buf {
+ char buf[MAX_SEQ_PRINTF_MAX_MEMCPY][MAX_SEQ_PRINTF_STR_LEN];
+};
+static DEFINE_PER_CPU(struct bpf_seq_printf_buf, bpf_seq_printf_buf);
+static DEFINE_PER_CPU(int, bpf_seq_printf_buf_used);
+
+BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
+ const void *, data, u32, data_len)
+{
+ int err = -EINVAL, fmt_cnt = 0, memcpy_cnt = 0;
+ int i, buf_used, copy_size, num_args;
+ u64 params[MAX_SEQ_PRINTF_VARARGS];
+ struct bpf_seq_printf_buf *bufs;
+ const u64 *args = data;
+
+ buf_used = this_cpu_inc_return(bpf_seq_printf_buf_used);
+ if (WARN_ON_ONCE(buf_used > 1)) {
+ err = -EBUSY;
+ goto out;
+ }
+
+ bufs = this_cpu_ptr(&bpf_seq_printf_buf);
+
+ /*
+ * bpf_check()->check_func_arg()->check_stack_boundary()
+ * guarantees that fmt points to bpf program stack,
+ * fmt_size bytes of it were initialized and fmt_size > 0
+ */
+ if (fmt[--fmt_size] != 0)
+ goto out;
+
+ if (data_len & 7)
+ goto out;
+
+ for (i = 0; i < fmt_size; i++) {
+ if (fmt[i] == '%') {
+ if (fmt[i + 1] == '%')
+ i++;
+ else if (!data || !data_len)
+ goto out;
+ }
+ }
+
+ num_args = data_len / 8;
+
+ /* check format string for allowed specifiers */
+ for (i = 0; i < fmt_size; i++) {
+ /* only printable ascii for now. */
+ if ((!isprint(fmt[i]) && !isspace(fmt[i])) || !isascii(fmt[i])) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (fmt[i] != '%')
+ continue;
+
+ if (fmt[i + 1] == '%') {
+ i++;
+ continue;
+ }
+
+ if (fmt_cnt >= MAX_SEQ_PRINTF_VARARGS) {
+ err = -E2BIG;
+ goto out;
+ }
+
+ if (fmt_cnt >= num_args) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ /* fmt[i] != 0 && fmt[last] == 0, so we can access fmt[i + 1] */
+ i++;
+
+ /* skip optional "[0 +-][num]" width formating field */
+ while (fmt[i] == '0' || fmt[i] == '+' || fmt[i] == '-' ||
+ fmt[i] == ' ')
+ i++;
+ if (fmt[i] >= '1' && fmt[i] <= '9') {
+ i++;
+ while (fmt[i] >= '0' && fmt[i] <= '9')
+ i++;
+ }
+
+ if (fmt[i] == 's') {
+ void *unsafe_ptr;
+
+ /* try our best to copy */
+ if (memcpy_cnt >= MAX_SEQ_PRINTF_MAX_MEMCPY) {
+ err = -E2BIG;
+ goto out;
+ }
+
+ unsafe_ptr = (void *)(long)args[fmt_cnt];
+ err = strncpy_from_kernel_nofault(bufs->buf[memcpy_cnt],
+ unsafe_ptr, MAX_SEQ_PRINTF_STR_LEN);
+ if (err < 0)
+ bufs->buf[memcpy_cnt][0] = '\0';
+ params[fmt_cnt] = (u64)(long)bufs->buf[memcpy_cnt];
+
+ fmt_cnt++;
+ memcpy_cnt++;
+ continue;
+ }
+
+ if (fmt[i] == 'p') {
+ if (fmt[i + 1] == 0 ||
+ fmt[i + 1] == 'K' ||
+ fmt[i + 1] == 'x' ||
+ fmt[i + 1] == 'B') {
+ /* just kernel pointers */
+ params[fmt_cnt] = args[fmt_cnt];
+ fmt_cnt++;
+ continue;
+ }
+
+ /* only support "%pI4", "%pi4", "%pI6" and "%pi6". */
+ if (fmt[i + 1] != 'i' && fmt[i + 1] != 'I') {
+ err = -EINVAL;
+ goto out;
+ }
+ if (fmt[i + 2] != '4' && fmt[i + 2] != '6') {
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (memcpy_cnt >= MAX_SEQ_PRINTF_MAX_MEMCPY) {
+ err = -E2BIG;
+ goto out;
+ }
+
+
+ copy_size = (fmt[i + 2] == '4') ? 4 : 16;
+
+ err = copy_from_kernel_nofault(bufs->buf[memcpy_cnt],
+ (void *) (long) args[fmt_cnt],
+ copy_size);
+ if (err < 0)
+ memset(bufs->buf[memcpy_cnt], 0, copy_size);
+ params[fmt_cnt] = (u64)(long)bufs->buf[memcpy_cnt];
+
+ i += 2;
+ fmt_cnt++;
+ memcpy_cnt++;
+ continue;
+ }
+
+ if (fmt[i] == 'l') {
+ i++;
+ if (fmt[i] == 'l')
+ i++;
+ }
+
+ if (fmt[i] != 'i' && fmt[i] != 'd' &&
+ fmt[i] != 'u' && fmt[i] != 'x' &&
+ fmt[i] != 'X') {
+ err = -EINVAL;
+ goto out;
+ }
+
+ params[fmt_cnt] = args[fmt_cnt];
+ fmt_cnt++;
+ }
+
+ /* Maximumly we can have MAX_SEQ_PRINTF_VARARGS parameter, just give
+ * all of them to seq_printf().
+ */
+ seq_printf(m, fmt, params[0], params[1], params[2], params[3],
+ params[4], params[5], params[6], params[7], params[8],
+ params[9], params[10], params[11]);
+
+ err = seq_has_overflowed(m) ? -EOVERFLOW : 0;
+out:
+ this_cpu_dec(bpf_seq_printf_buf_used);
+ return err;
+}
+
+BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file)
+
+static const struct bpf_func_proto bpf_seq_printf_proto = {
+ .func = bpf_seq_printf,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_BTF_ID,
+ .arg1_btf_id = &btf_seq_file_ids[0],
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE,
+ .arg4_type = ARG_PTR_TO_MEM_OR_NULL,
+ .arg5_type = ARG_CONST_SIZE_OR_ZERO,
+};
+
+BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
+{
+ return seq_write(m, data, len) ? -EOVERFLOW : 0;
+}
+
+static const struct bpf_func_proto bpf_seq_write_proto = {
+ .func = bpf_seq_write,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_BTF_ID,
+ .arg1_btf_id = &btf_seq_file_ids[0],
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE_OR_ZERO,
+};
+
+BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr,
+ u32, btf_ptr_size, u64, flags)
+{
+ const struct btf *btf;
+ s32 btf_id;
+ int ret;
+
+ ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
+ if (ret)
+ return ret;
+
+ return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags);
+}
+
+static const struct bpf_func_proto bpf_seq_printf_btf_proto = {
+ .func = bpf_seq_printf_btf,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_BTF_ID,
+ .arg1_btf_id = &btf_seq_file_ids[0],
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg4_type = ARG_ANYTHING,
+};
+
+static __always_inline int
+get_map_perf_counter(struct bpf_map *map, u64 flags,
+ u64 *value, u64 *enabled, u64 *running)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ unsigned int cpu = smp_processor_id();
+ u64 index = flags & BPF_F_INDEX_MASK;
+ struct bpf_event_entry *ee;
+
+ if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
+ return -EINVAL;
+ if (index == BPF_F_CURRENT_CPU)
+ index = cpu;
+ if (unlikely(index >= array->map.max_entries))
+ return -E2BIG;
+
+ ee = READ_ONCE(array->ptrs[index]);
+ if (!ee)
+ return -ENOENT;
+
+ return perf_event_read_local(ee->event, value, enabled, running);
+}
+
+BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
+{
+ u64 value = 0;
+ int err;
+
+ err = get_map_perf_counter(map, flags, &value, NULL, NULL);
+ /*
+ * this api is ugly since we miss [-22..-2] range of valid
+ * counter values, but that's uapi
+ */
+ if (err)
+ return err;
+ return value;
+}
+
+static const struct bpf_func_proto bpf_perf_event_read_proto = {
+ .func = bpf_perf_event_read,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_ANYTHING,
+};
+
+BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
+ struct bpf_perf_event_value *, buf, u32, size)
+{
+ int err = -EINVAL;
+
+ if (unlikely(size != sizeof(struct bpf_perf_event_value)))
+ goto clear;
+ err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
+ &buf->running);
+ if (unlikely(err))
+ goto clear;
+ return 0;
+clear:
+ memset(buf, 0, size);
+ return err;
+}
+
+static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
+ .func = bpf_perf_event_read_value,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg4_type = ARG_CONST_SIZE,
+};
+
+static __always_inline u64
+__bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
+ u64 flags, struct perf_sample_data *sd)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ unsigned int cpu = smp_processor_id();
+ u64 index = flags & BPF_F_INDEX_MASK;
+ struct bpf_event_entry *ee;
+ struct perf_event *event;
+
+ if (index == BPF_F_CURRENT_CPU)
+ index = cpu;
+ if (unlikely(index >= array->map.max_entries))
+ return -E2BIG;
+
+ ee = READ_ONCE(array->ptrs[index]);
+ if (!ee)
+ return -ENOENT;
+
+ event = ee->event;
+ if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
+ event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
+ return -EINVAL;
+
+ if (unlikely(event->oncpu != cpu))
+ return -EOPNOTSUPP;
+
+ return perf_event_output(event, sd, regs);
+}
+
+/*
+ * Support executing tracepoints in normal, irq, and nmi context that each call
+ * bpf_perf_event_output
+ */
+struct bpf_trace_sample_data {
+ struct perf_sample_data sds[3];
+};
+
+static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
+static DEFINE_PER_CPU(int, bpf_trace_nest_level);
+BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
+ u64, flags, void *, data, u64, size)
+{
+ struct bpf_trace_sample_data *sds = this_cpu_ptr(&bpf_trace_sds);
+ int nest_level = this_cpu_inc_return(bpf_trace_nest_level);
+ struct perf_raw_record raw = {
+ .frag = {
+ .size = size,
+ .data = data,
+ },
+ };
+ struct perf_sample_data *sd;
+ int err;
+
+ if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
+ err = -EBUSY;
+ goto out;
+ }
+
+ sd = &sds->sds[nest_level - 1];
+
+ if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ perf_sample_data_init(sd, 0, 0);
+ sd->raw = &raw;
+
+ err = __bpf_perf_event_output(regs, map, flags, sd);
+
+out:
+ this_cpu_dec(bpf_trace_nest_level);
+ return err;
+}
+
+static const struct bpf_func_proto bpf_perf_event_output_proto = {
+ .func = bpf_perf_event_output,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
+ .arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_PTR_TO_MEM,
+ .arg5_type = ARG_CONST_SIZE_OR_ZERO,
+};
+
+static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
+struct bpf_nested_pt_regs {
+ struct pt_regs regs[3];
+};
+static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
+static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
+
+u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
+ void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
+{
+ struct perf_raw_frag frag = {
+ .copy = ctx_copy,
+ .size = ctx_size,
+ .data = ctx,
+ };
+ struct perf_raw_record raw = {
+ .frag = {
+ {
+ .next = ctx_size ? &frag : NULL,
+ },
+ .size = meta_size,
+ .data = meta,
+ },
+ };
+ struct perf_sample_data *sd;
+ struct pt_regs *regs;
+ int nest_level;
+ u64 ret;
+
+ preempt_disable();
+ nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
+
+ if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
+ ret = -EBUSY;
+ goto out;
+ }
+ sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
+ regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
+
+ perf_fetch_caller_regs(regs);
+ perf_sample_data_init(sd, 0, 0);
+ sd->raw = &raw;
+
+ ret = __bpf_perf_event_output(regs, map, flags, sd);
+out:
+ this_cpu_dec(bpf_event_output_nest_level);
+ preempt_enable();
+ return ret;
+}
+
+BPF_CALL_0(bpf_get_current_task)
+{
+ return (long) current;
+}
+
+const struct bpf_func_proto bpf_get_current_task_proto = {
+ .func = bpf_get_current_task,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+};
+
+BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ struct cgroup *cgrp;
+
+ if (unlikely(idx >= array->map.max_entries))
+ return -E2BIG;
+
+ cgrp = READ_ONCE(array->ptrs[idx]);
+ if (unlikely(!cgrp))
+ return -EAGAIN;
+
+ return task_under_cgroup_hierarchy(current, cgrp);
+}
+
+static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
+ .func = bpf_current_task_under_cgroup,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_ANYTHING,
+};
+
+struct send_signal_irq_work {
+ struct irq_work irq_work;
+ struct task_struct *task;
+ u32 sig;
+ enum pid_type type;
+};
+
+static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
+
+static void do_bpf_send_signal(struct irq_work *entry)
+{
+ struct send_signal_irq_work *work;
+
+ work = container_of(entry, struct send_signal_irq_work, irq_work);
+ group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
+ put_task_struct(work->task);
+}
+
+static int bpf_send_signal_common(u32 sig, enum pid_type type)
+{
+ struct send_signal_irq_work *work = NULL;
+
+ /* Similar to bpf_probe_write_user, task needs to be
+ * in a sound condition and kernel memory access be
+ * permitted in order to send signal to the current
+ * task.
+ */
+ if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
+ return -EPERM;
+ if (unlikely(uaccess_kernel()))
+ return -EPERM;
+ if (unlikely(!nmi_uaccess_okay()))
+ return -EPERM;
+ /* Task should not be pid=1 to avoid kernel panic. */
+ if (unlikely(is_global_init(current)))
+ return -EPERM;
+
+ if (irqs_disabled()) {
+ /* Do an early check on signal validity. Otherwise,
+ * the error is lost in deferred irq_work.
+ */
+ if (unlikely(!valid_signal(sig)))
+ return -EINVAL;
+
+ work = this_cpu_ptr(&send_signal_work);
+ if (atomic_read(&work->irq_work.flags) & IRQ_WORK_BUSY)
+ return -EBUSY;
+
+ /* Add the current task, which is the target of sending signal,
+ * to the irq_work. The current task may change when queued
+ * irq works get executed.
+ */
+ work->task = get_task_struct(current);
+ work->sig = sig;
+ work->type = type;
+ irq_work_queue(&work->irq_work);
+ return 0;
+ }
+
+ return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
+}
+
+BPF_CALL_1(bpf_send_signal, u32, sig)
+{
+ return bpf_send_signal_common(sig, PIDTYPE_TGID);
+}
+
+static const struct bpf_func_proto bpf_send_signal_proto = {
+ .func = bpf_send_signal,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_ANYTHING,
+};
+
+BPF_CALL_1(bpf_send_signal_thread, u32, sig)
+{
+ return bpf_send_signal_common(sig, PIDTYPE_PID);
+}
+
+static const struct bpf_func_proto bpf_send_signal_thread_proto = {
+ .func = bpf_send_signal_thread,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_ANYTHING,
+};
+
+BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz)
+{
+ struct path copy;
+ long len;
+ char *p;
+
+ if (!sz)
+ return 0;
+
+ /*
+ * The path pointer is verified as trusted and safe to use,
+ * but let's double check it's valid anyway to workaround
+ * potentially broken verifier.
+ */
+ len = copy_from_kernel_nofault(&copy, path, sizeof(*path));
+ if (len < 0)
+ return len;
+
+ p = d_path(&copy, buf, sz);
+ if (IS_ERR(p)) {
+ len = PTR_ERR(p);
+ } else {
+ len = buf + sz - p;
+ memmove(buf, p, len);
+ }
+
+ return len;
+}
+
+BTF_SET_START(btf_allowlist_d_path)
+#ifdef CONFIG_SECURITY
+BTF_ID(func, security_file_permission)
+BTF_ID(func, security_inode_getattr)
+BTF_ID(func, security_file_open)
+#endif
+#ifdef CONFIG_SECURITY_PATH
+BTF_ID(func, security_path_truncate)
+#endif
+BTF_ID(func, vfs_truncate)
+BTF_ID(func, vfs_fallocate)
+BTF_ID(func, dentry_open)
+BTF_ID(func, vfs_getattr)
+BTF_ID(func, filp_close)
+BTF_SET_END(btf_allowlist_d_path)
+
+static bool bpf_d_path_allowed(const struct bpf_prog *prog)
+{
+ return btf_id_set_contains(&btf_allowlist_d_path, prog->aux->attach_btf_id);
+}
+
+BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path)
+
+static const struct bpf_func_proto bpf_d_path_proto = {
+ .func = bpf_d_path,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_BTF_ID,
+ .arg1_btf_id = &bpf_d_path_btf_ids[0],
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE_OR_ZERO,
+ .allowed = bpf_d_path_allowed,
+};
+
+#define BTF_F_ALL (BTF_F_COMPACT | BTF_F_NONAME | \
+ BTF_F_PTR_RAW | BTF_F_ZERO)
+
+static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
+ u64 flags, const struct btf **btf,
+ s32 *btf_id)
+{
+ const struct btf_type *t;
+
+ if (unlikely(flags & ~(BTF_F_ALL)))
+ return -EINVAL;
+
+ if (btf_ptr_size != sizeof(struct btf_ptr))
+ return -EINVAL;
+
+ *btf = bpf_get_btf_vmlinux();
+
+ if (IS_ERR_OR_NULL(*btf))
+ return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL;
+
+ if (ptr->type_id > 0)
+ *btf_id = ptr->type_id;
+ else
+ return -EINVAL;
+
+ if (*btf_id > 0)
+ t = btf_type_by_id(*btf, *btf_id);
+ if (*btf_id <= 0 || !t)
+ return -ENOENT;
+
+ return 0;
+}
+
+BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr,
+ u32, btf_ptr_size, u64, flags)
+{
+ const struct btf *btf;
+ s32 btf_id;
+ int ret;
+
+ ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
+ if (ret)
+ return ret;
+
+ return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size,
+ flags);
+}
+
+const struct bpf_func_proto bpf_snprintf_btf_proto = {
+ .func = bpf_snprintf_btf,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_MEM,
+ .arg2_type = ARG_CONST_SIZE,
+ .arg3_type = ARG_PTR_TO_MEM,
+ .arg4_type = ARG_CONST_SIZE,
+ .arg5_type = ARG_ANYTHING,
+};
+
+const struct bpf_func_proto *
+bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_map_lookup_elem:
+ return &bpf_map_lookup_elem_proto;
+ case BPF_FUNC_map_update_elem:
+ return &bpf_map_update_elem_proto;
+ case BPF_FUNC_map_delete_elem:
+ return &bpf_map_delete_elem_proto;
+ case BPF_FUNC_map_push_elem:
+ return &bpf_map_push_elem_proto;
+ case BPF_FUNC_map_pop_elem:
+ return &bpf_map_pop_elem_proto;
+ case BPF_FUNC_map_peek_elem:
+ return &bpf_map_peek_elem_proto;
+ case BPF_FUNC_ktime_get_ns:
+ return &bpf_ktime_get_ns_proto;
+ case BPF_FUNC_ktime_get_boot_ns:
+ return &bpf_ktime_get_boot_ns_proto;
+ case BPF_FUNC_tail_call:
+ return &bpf_tail_call_proto;
+ case BPF_FUNC_get_current_pid_tgid:
+ return &bpf_get_current_pid_tgid_proto;
+ case BPF_FUNC_get_current_task:
+ return &bpf_get_current_task_proto;
+ case BPF_FUNC_get_current_uid_gid:
+ return &bpf_get_current_uid_gid_proto;
+ case BPF_FUNC_get_current_comm:
+ return &bpf_get_current_comm_proto;
+ case BPF_FUNC_trace_printk:
+ return bpf_get_trace_printk_proto();
+ case BPF_FUNC_get_smp_processor_id:
+ return &bpf_get_smp_processor_id_proto;
+ case BPF_FUNC_get_numa_node_id:
+ return &bpf_get_numa_node_id_proto;
+ case BPF_FUNC_perf_event_read:
+ return &bpf_perf_event_read_proto;
+ case BPF_FUNC_current_task_under_cgroup:
+ return &bpf_current_task_under_cgroup_proto;
+ case BPF_FUNC_get_prandom_u32:
+ return &bpf_get_prandom_u32_proto;
+ case BPF_FUNC_probe_write_user:
+ return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ?
+ NULL : bpf_get_probe_write_proto();
+ case BPF_FUNC_probe_read_user:
+ return &bpf_probe_read_user_proto;
+ case BPF_FUNC_probe_read_kernel:
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_kernel_proto;
+ case BPF_FUNC_probe_read_user_str:
+ return &bpf_probe_read_user_str_proto;
+ case BPF_FUNC_probe_read_kernel_str:
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_kernel_str_proto;
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+ case BPF_FUNC_probe_read:
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_compat_proto;
+ case BPF_FUNC_probe_read_str:
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_compat_str_proto;
+#endif
+#ifdef CONFIG_CGROUPS
+ case BPF_FUNC_get_current_cgroup_id:
+ return &bpf_get_current_cgroup_id_proto;
+#endif
+ case BPF_FUNC_send_signal:
+ return &bpf_send_signal_proto;
+ case BPF_FUNC_send_signal_thread:
+ return &bpf_send_signal_thread_proto;
+ case BPF_FUNC_perf_event_read_value:
+ return &bpf_perf_event_read_value_proto;
+ case BPF_FUNC_get_ns_current_pid_tgid:
+ return &bpf_get_ns_current_pid_tgid_proto;
+ case BPF_FUNC_ringbuf_output:
+ return &bpf_ringbuf_output_proto;
+ case BPF_FUNC_ringbuf_reserve:
+ return &bpf_ringbuf_reserve_proto;
+ case BPF_FUNC_ringbuf_submit:
+ return &bpf_ringbuf_submit_proto;
+ case BPF_FUNC_ringbuf_discard:
+ return &bpf_ringbuf_discard_proto;
+ case BPF_FUNC_ringbuf_query:
+ return &bpf_ringbuf_query_proto;
+ case BPF_FUNC_jiffies64:
+ return &bpf_jiffies64_proto;
+ case BPF_FUNC_get_task_stack:
+ return &bpf_get_task_stack_proto;
+ case BPF_FUNC_copy_from_user:
+ return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL;
+ case BPF_FUNC_snprintf_btf:
+ return &bpf_snprintf_btf_proto;
+ case BPF_FUNC_per_cpu_ptr:
+ return &bpf_per_cpu_ptr_proto;
+ case BPF_FUNC_this_cpu_ptr:
+ return &bpf_this_cpu_ptr_proto;
+ default:
+ return NULL;
+ }
+}
+
+static const struct bpf_func_proto *
+kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_perf_event_output:
+ return &bpf_perf_event_output_proto;
+ case BPF_FUNC_get_stackid:
+ return &bpf_get_stackid_proto;
+ case BPF_FUNC_get_stack:
+ return &bpf_get_stack_proto;
+#ifdef CONFIG_BPF_KPROBE_OVERRIDE
+ case BPF_FUNC_override_return:
+ return &bpf_override_return_proto;
+#endif
+ default:
+ return bpf_tracing_func_proto(func_id, prog);
+ }
+}
+
+/* bpf+kprobe programs can access fields of 'struct pt_regs' */
+static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (off < 0 || off >= sizeof(struct pt_regs))
+ return false;
+ if (type != BPF_READ)
+ return false;
+ if (off % size != 0)
+ return false;
+ /*
+ * Assertion for 32 bit to make sure last 8 byte access
+ * (BPF_DW) to the last 4 byte member is disallowed.
+ */
+ if (off + size > sizeof(struct pt_regs))
+ return false;
+
+ return true;
+}
+
+const struct bpf_verifier_ops kprobe_verifier_ops = {
+ .get_func_proto = kprobe_prog_func_proto,
+ .is_valid_access = kprobe_prog_is_valid_access,
+};
+
+const struct bpf_prog_ops kprobe_prog_ops = {
+};
+
+BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
+ u64, flags, void *, data, u64, size)
+{
+ struct pt_regs *regs = *(struct pt_regs **)tp_buff;
+
+ /*
+ * r1 points to perf tracepoint buffer where first 8 bytes are hidden
+ * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
+ * from there and call the same bpf_perf_event_output() helper inline.
+ */
+ return ____bpf_perf_event_output(regs, map, flags, data, size);
+}
+
+static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
+ .func = bpf_perf_event_output_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
+ .arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_PTR_TO_MEM,
+ .arg5_type = ARG_CONST_SIZE_OR_ZERO,
+};
+
+BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
+ u64, flags)
+{
+ struct pt_regs *regs = *(struct pt_regs **)tp_buff;
+
+ /*
+ * Same comment as in bpf_perf_event_output_tp(), only that this time
+ * the other helper's function body cannot be inlined due to being
+ * external, thus we need to call raw helper function.
+ */
+ return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
+ flags, 0, 0);
+}
+
+static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
+ .func = bpf_get_stackid_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
+ .arg3_type = ARG_ANYTHING,
+};
+
+BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
+ u64, flags)
+{
+ struct pt_regs *regs = *(struct pt_regs **)tp_buff;
+
+ return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
+ (unsigned long) size, flags, 0);
+}
+
+static const struct bpf_func_proto bpf_get_stack_proto_tp = {
+ .func = bpf_get_stack_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg3_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg4_type = ARG_ANYTHING,
+};
+
+static const struct bpf_func_proto *
+tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_perf_event_output:
+ return &bpf_perf_event_output_proto_tp;
+ case BPF_FUNC_get_stackid:
+ return &bpf_get_stackid_proto_tp;
+ case BPF_FUNC_get_stack:
+ return &bpf_get_stack_proto_tp;
+ default:
+ return bpf_tracing_func_proto(func_id, prog);
+ }
+}
+
+static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
+ return false;
+ if (type != BPF_READ)
+ return false;
+ if (off % size != 0)
+ return false;
+
+ BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
+ return true;
+}
+
+const struct bpf_verifier_ops tracepoint_verifier_ops = {
+ .get_func_proto = tp_prog_func_proto,
+ .is_valid_access = tp_prog_is_valid_access,
+};
+
+const struct bpf_prog_ops tracepoint_prog_ops = {
+};
+
+BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
+ struct bpf_perf_event_value *, buf, u32, size)
+{
+ int err = -EINVAL;
+
+ if (unlikely(size != sizeof(struct bpf_perf_event_value)))
+ goto clear;
+ err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
+ &buf->running);
+ if (unlikely(err))
+ goto clear;
+ return 0;
+clear:
+ memset(buf, 0, size);
+ return err;
+}
+
+static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
+ .func = bpf_perf_prog_read_value,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_UNINIT_MEM,
+ .arg3_type = ARG_CONST_SIZE,
+};
+
+BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
+ void *, buf, u32, size, u64, flags)
+{
+ static const u32 br_entry_size = sizeof(struct perf_branch_entry);
+ struct perf_branch_stack *br_stack = ctx->data->br_stack;
+ u32 to_copy;
+
+ if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
+ return -EINVAL;
+
+ if (unlikely(!br_stack))
+ return -ENOENT;
+
+ if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
+ return br_stack->nr * br_entry_size;
+
+ if (!buf || (size % br_entry_size != 0))
+ return -EINVAL;
+
+ to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
+ memcpy(buf, br_stack->entries, to_copy);
+
+ return to_copy;
+}
+
+static const struct bpf_func_proto bpf_read_branch_records_proto = {
+ .func = bpf_read_branch_records,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_MEM_OR_NULL,
+ .arg3_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg4_type = ARG_ANYTHING,
+};
+
+static const struct bpf_func_proto *
+pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_perf_event_output:
+ return &bpf_perf_event_output_proto_tp;
+ case BPF_FUNC_get_stackid:
+ return &bpf_get_stackid_proto_pe;
+ case BPF_FUNC_get_stack:
+ return &bpf_get_stack_proto_pe;
+ case BPF_FUNC_perf_prog_read_value:
+ return &bpf_perf_prog_read_value_proto;
+ case BPF_FUNC_read_branch_records:
+ return &bpf_read_branch_records_proto;
+ default:
+ return bpf_tracing_func_proto(func_id, prog);
+ }
+}
+
+/*
+ * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
+ * to avoid potential recursive reuse issue when/if tracepoints are added
+ * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
+ *
+ * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
+ * in normal, irq, and nmi context.
+ */
+struct bpf_raw_tp_regs {
+ struct pt_regs regs[3];
+};
+static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
+static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
+static struct pt_regs *get_bpf_raw_tp_regs(void)
+{
+ struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
+ int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
+
+ if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
+ this_cpu_dec(bpf_raw_tp_nest_level);
+ return ERR_PTR(-EBUSY);
+ }
+
+ return &tp_regs->regs[nest_level - 1];
+}
+
+static void put_bpf_raw_tp_regs(void)
+{
+ this_cpu_dec(bpf_raw_tp_nest_level);
+}
+
+BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
+ struct bpf_map *, map, u64, flags, void *, data, u64, size)
+{
+ struct pt_regs *regs = get_bpf_raw_tp_regs();
+ int ret;
+
+ if (IS_ERR(regs))
+ return PTR_ERR(regs);
+
+ perf_fetch_caller_regs(regs);
+ ret = ____bpf_perf_event_output(regs, map, flags, data, size);
+
+ put_bpf_raw_tp_regs();
+ return ret;
+}
+
+static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
+ .func = bpf_perf_event_output_raw_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
+ .arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_PTR_TO_MEM,
+ .arg5_type = ARG_CONST_SIZE_OR_ZERO,
+};
+
+extern const struct bpf_func_proto bpf_skb_output_proto;
+extern const struct bpf_func_proto bpf_xdp_output_proto;
+
+BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
+ struct bpf_map *, map, u64, flags)
+{
+ struct pt_regs *regs = get_bpf_raw_tp_regs();
+ int ret;
+
+ if (IS_ERR(regs))
+ return PTR_ERR(regs);
+
+ perf_fetch_caller_regs(regs);
+ /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
+ ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
+ flags, 0, 0);
+ put_bpf_raw_tp_regs();
+ return ret;
+}
+
+static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
+ .func = bpf_get_stackid_raw_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_CONST_MAP_PTR,
+ .arg3_type = ARG_ANYTHING,
+};
+
+BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
+ void *, buf, u32, size, u64, flags)
+{
+ struct pt_regs *regs = get_bpf_raw_tp_regs();
+ int ret;
+
+ if (IS_ERR(regs))
+ return PTR_ERR(regs);
+
+ perf_fetch_caller_regs(regs);
+ ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
+ (unsigned long) size, flags, 0);
+ put_bpf_raw_tp_regs();
+ return ret;
+}
+
+static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
+ .func = bpf_get_stack_raw_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg4_type = ARG_ANYTHING,
+};
+
+static const struct bpf_func_proto *
+raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_perf_event_output:
+ return &bpf_perf_event_output_proto_raw_tp;
+ case BPF_FUNC_get_stackid:
+ return &bpf_get_stackid_proto_raw_tp;
+ case BPF_FUNC_get_stack:
+ return &bpf_get_stack_proto_raw_tp;
+ default:
+ return bpf_tracing_func_proto(func_id, prog);
+ }
+}
+
+const struct bpf_func_proto *
+tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+#ifdef CONFIG_NET
+ case BPF_FUNC_skb_output:
+ return &bpf_skb_output_proto;
+ case BPF_FUNC_xdp_output:
+ return &bpf_xdp_output_proto;
+ case BPF_FUNC_skc_to_tcp6_sock:
+ return &bpf_skc_to_tcp6_sock_proto;
+ case BPF_FUNC_skc_to_tcp_sock:
+ return &bpf_skc_to_tcp_sock_proto;
+ case BPF_FUNC_skc_to_tcp_timewait_sock:
+ return &bpf_skc_to_tcp_timewait_sock_proto;
+ case BPF_FUNC_skc_to_tcp_request_sock:
+ return &bpf_skc_to_tcp_request_sock_proto;
+ case BPF_FUNC_skc_to_udp6_sock:
+ return &bpf_skc_to_udp6_sock_proto;
+#endif
+ case BPF_FUNC_seq_printf:
+ return prog->expected_attach_type == BPF_TRACE_ITER ?
+ &bpf_seq_printf_proto :
+ NULL;
+ case BPF_FUNC_seq_write:
+ return prog->expected_attach_type == BPF_TRACE_ITER ?
+ &bpf_seq_write_proto :
+ NULL;
+ case BPF_FUNC_seq_printf_btf:
+ return prog->expected_attach_type == BPF_TRACE_ITER ?
+ &bpf_seq_printf_btf_proto :
+ NULL;
+ case BPF_FUNC_d_path:
+ return &bpf_d_path_proto;
+ default:
+ return raw_tp_prog_func_proto(func_id, prog);
+ }
+}
+
+static bool raw_tp_prog_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
+ return false;
+ if (type != BPF_READ)
+ return false;
+ if (off % size != 0)
+ return false;
+ return true;
+}
+
+static bool tracing_prog_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (off < 0 || off >= sizeof(__u64) * MAX_BPF_FUNC_ARGS)
+ return false;
+ if (type != BPF_READ)
+ return false;
+ if (off % size != 0)
+ return false;
+ return btf_ctx_access(off, size, type, prog, info);
+}
+
+int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
+ const union bpf_attr *kattr,
+ union bpf_attr __user *uattr)
+{
+ return -ENOTSUPP;
+}
+
+const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
+ .get_func_proto = raw_tp_prog_func_proto,
+ .is_valid_access = raw_tp_prog_is_valid_access,
+};
+
+const struct bpf_prog_ops raw_tracepoint_prog_ops = {
+#ifdef CONFIG_NET
+ .test_run = bpf_prog_test_run_raw_tp,
+#endif
+};
+
+const struct bpf_verifier_ops tracing_verifier_ops = {
+ .get_func_proto = tracing_prog_func_proto,
+ .is_valid_access = tracing_prog_is_valid_access,
+};
+
+const struct bpf_prog_ops tracing_prog_ops = {
+ .test_run = bpf_prog_test_run_tracing,
+};
+
+static bool raw_tp_writable_prog_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (off == 0) {
+ if (size != sizeof(u64) || type != BPF_READ)
+ return false;
+ info->reg_type = PTR_TO_TP_BUFFER;
+ }
+ return raw_tp_prog_is_valid_access(off, size, type, prog, info);
+}
+
+const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
+ .get_func_proto = raw_tp_prog_func_proto,
+ .is_valid_access = raw_tp_writable_prog_is_valid_access,
+};
+
+const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
+};
+
+static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ const int size_u64 = sizeof(u64);
+
+ if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
+ return false;
+ if (type != BPF_READ)
+ return false;
+ if (off % size != 0) {
+ if (sizeof(unsigned long) != 4)
+ return false;
+ if (size != 8)
+ return false;
+ if (off % size != 4)
+ return false;
+ }
+
+ switch (off) {
+ case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
+ bpf_ctx_record_field_size(info, size_u64);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
+ return false;
+ break;
+ case bpf_ctx_range(struct bpf_perf_event_data, addr):
+ bpf_ctx_record_field_size(info, size_u64);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
+ return false;
+ break;
+ default:
+ if (size != sizeof(long))
+ return false;
+ }
+
+ return true;
+}
+
+static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
+ const struct bpf_insn *si,
+ struct bpf_insn *insn_buf,
+ struct bpf_prog *prog, u32 *target_size)
+{
+ struct bpf_insn *insn = insn_buf;
+
+ switch (si->off) {
+ case offsetof(struct bpf_perf_event_data, sample_period):
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
+ data), si->dst_reg, si->src_reg,
+ offsetof(struct bpf_perf_event_data_kern, data));
+ *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
+ bpf_target_off(struct perf_sample_data, period, 8,
+ target_size));
+ break;
+ case offsetof(struct bpf_perf_event_data, addr):
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
+ data), si->dst_reg, si->src_reg,
+ offsetof(struct bpf_perf_event_data_kern, data));
+ *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
+ bpf_target_off(struct perf_sample_data, addr, 8,
+ target_size));
+ break;
+ default:
+ *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
+ regs), si->dst_reg, si->src_reg,
+ offsetof(struct bpf_perf_event_data_kern, regs));
+ *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
+ si->off);
+ break;
+ }
+
+ return insn - insn_buf;
+}
+
+const struct bpf_verifier_ops perf_event_verifier_ops = {
+ .get_func_proto = pe_prog_func_proto,
+ .is_valid_access = pe_prog_is_valid_access,
+ .convert_ctx_access = pe_prog_convert_ctx_access,
+};
+
+const struct bpf_prog_ops perf_event_prog_ops = {
+};
+
+static DEFINE_MUTEX(bpf_event_mutex);
+
+#define BPF_TRACE_MAX_PROGS 64
+
+int perf_event_attach_bpf_prog(struct perf_event *event,
+ struct bpf_prog *prog)
+{
+ struct bpf_prog_array *old_array;
+ struct bpf_prog_array *new_array;
+ int ret = -EEXIST;
+
+ /*
+ * Kprobe override only works if they are on the function entry,
+ * and only if they are on the opt-in list.
+ */
+ if (prog->kprobe_override &&
+ (!trace_kprobe_on_func_entry(event->tp_event) ||
+ !trace_kprobe_error_injectable(event->tp_event)))
+ return -EINVAL;
+
+ mutex_lock(&bpf_event_mutex);
+
+ if (event->prog)
+ goto unlock;
+
+ old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
+ if (old_array &&
+ bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
+ ret = -E2BIG;
+ goto unlock;
+ }
+
+ ret = bpf_prog_array_copy(old_array, NULL, prog, &new_array);
+ if (ret < 0)
+ goto unlock;
+
+ /* set the new array to event->tp_event and set event->prog */
+ event->prog = prog;
+ rcu_assign_pointer(event->tp_event->prog_array, new_array);
+ bpf_prog_array_free(old_array);
+
+unlock:
+ mutex_unlock(&bpf_event_mutex);
+ return ret;
+}
+
+void perf_event_detach_bpf_prog(struct perf_event *event)
+{
+ struct bpf_prog_array *old_array;
+ struct bpf_prog_array *new_array;
+ int ret;
+
+ mutex_lock(&bpf_event_mutex);
+
+ if (!event->prog)
+ goto unlock;
+
+ old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
+ ret = bpf_prog_array_copy(old_array, event->prog, NULL, &new_array);
+ if (ret == -ENOENT)
+ goto unlock;
+ if (ret < 0) {
+ bpf_prog_array_delete_safe(old_array, event->prog);
+ } else {
+ rcu_assign_pointer(event->tp_event->prog_array, new_array);
+ bpf_prog_array_free(old_array);
+ }
+
+ bpf_prog_put(event->prog);
+ event->prog = NULL;
+
+unlock:
+ mutex_unlock(&bpf_event_mutex);
+}
+
+int perf_event_query_prog_array(struct perf_event *event, void __user *info)
+{
+ struct perf_event_query_bpf __user *uquery = info;
+ struct perf_event_query_bpf query = {};
+ struct bpf_prog_array *progs;
+ u32 *ids, prog_cnt, ids_len;
+ int ret;
+
+ if (!perfmon_capable())
+ return -EPERM;
+ if (event->attr.type != PERF_TYPE_TRACEPOINT)
+ return -EINVAL;
+ if (copy_from_user(&query, uquery, sizeof(query)))
+ return -EFAULT;
+
+ ids_len = query.ids_len;
+ if (ids_len > BPF_TRACE_MAX_PROGS)
+ return -E2BIG;
+ ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
+ if (!ids)
+ return -ENOMEM;
+ /*
+ * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
+ * is required when user only wants to check for uquery->prog_cnt.
+ * There is no need to check for it since the case is handled
+ * gracefully in bpf_prog_array_copy_info.
+ */
+
+ mutex_lock(&bpf_event_mutex);
+ progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
+ ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
+ mutex_unlock(&bpf_event_mutex);
+
+ if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
+ copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
+ ret = -EFAULT;
+
+ kfree(ids);
+ return ret;
+}
+
+extern struct bpf_raw_event_map __start__bpf_raw_tp[];
+extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
+
+struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
+{
+ struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
+
+ for (; btp < __stop__bpf_raw_tp; btp++) {
+ if (!strcmp(btp->tp->name, name))
+ return btp;
+ }
+
+ return bpf_get_raw_tracepoint_module(name);
+}
+
+void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
+{
+ struct module *mod;
+
+ preempt_disable();
+ mod = __module_address((unsigned long)btp);
+ module_put(mod);
+ preempt_enable();
+}
+
+static __always_inline
+void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
+{
+ cant_sleep();
+ rcu_read_lock();
+ (void) BPF_PROG_RUN(prog, args);
+ rcu_read_unlock();
+}
+
+#define UNPACK(...) __VA_ARGS__
+#define REPEAT_1(FN, DL, X, ...) FN(X)
+#define REPEAT_2(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
+#define REPEAT_3(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
+#define REPEAT_4(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
+#define REPEAT_5(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
+#define REPEAT_6(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
+#define REPEAT_7(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
+#define REPEAT_8(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
+#define REPEAT_9(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
+#define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
+#define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
+#define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
+#define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__)
+
+#define SARG(X) u64 arg##X
+#define COPY(X) args[X] = arg##X
+
+#define __DL_COM (,)
+#define __DL_SEM (;)
+
+#define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
+
+#define BPF_TRACE_DEFN_x(x) \
+ void bpf_trace_run##x(struct bpf_prog *prog, \
+ REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \
+ { \
+ u64 args[x]; \
+ REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \
+ __bpf_trace_run(prog, args); \
+ } \
+ EXPORT_SYMBOL_GPL(bpf_trace_run##x)
+BPF_TRACE_DEFN_x(1);
+BPF_TRACE_DEFN_x(2);
+BPF_TRACE_DEFN_x(3);
+BPF_TRACE_DEFN_x(4);
+BPF_TRACE_DEFN_x(5);
+BPF_TRACE_DEFN_x(6);
+BPF_TRACE_DEFN_x(7);
+BPF_TRACE_DEFN_x(8);
+BPF_TRACE_DEFN_x(9);
+BPF_TRACE_DEFN_x(10);
+BPF_TRACE_DEFN_x(11);
+BPF_TRACE_DEFN_x(12);
+
+static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
+{
+ struct tracepoint *tp = btp->tp;
+
+ /*
+ * check that program doesn't access arguments beyond what's
+ * available in this tracepoint
+ */
+ if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
+ return -EINVAL;
+
+ if (prog->aux->max_tp_access > btp->writable_size)
+ return -EINVAL;
+
+ return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func,
+ prog);
+}
+
+int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
+{
+ return __bpf_probe_register(btp, prog);
+}
+
+int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
+{
+ return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
+}
+
+int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
+ u32 *fd_type, const char **buf,
+ u64 *probe_offset, u64 *probe_addr)
+{
+ bool is_tracepoint, is_syscall_tp;
+ struct bpf_prog *prog;
+ int flags, err = 0;
+
+ prog = event->prog;
+ if (!prog)
+ return -ENOENT;
+
+ /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
+ if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
+ return -EOPNOTSUPP;
+
+ *prog_id = prog->aux->id;
+ flags = event->tp_event->flags;
+ is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
+ is_syscall_tp = is_syscall_trace_event(event->tp_event);
+
+ if (is_tracepoint || is_syscall_tp) {
+ *buf = is_tracepoint ? event->tp_event->tp->name
+ : event->tp_event->name;
+ *fd_type = BPF_FD_TYPE_TRACEPOINT;
+ *probe_offset = 0x0;
+ *probe_addr = 0x0;
+ } else {
+ /* kprobe/uprobe */
+ err = -EOPNOTSUPP;
+#ifdef CONFIG_KPROBE_EVENTS
+ if (flags & TRACE_EVENT_FL_KPROBE)
+ err = bpf_get_kprobe_info(event, fd_type, buf,
+ probe_offset, probe_addr,
+ event->attr.type == PERF_TYPE_TRACEPOINT);
+#endif
+#ifdef CONFIG_UPROBE_EVENTS
+ if (flags & TRACE_EVENT_FL_UPROBE)
+ err = bpf_get_uprobe_info(event, fd_type, buf,
+ probe_offset, probe_addr,
+ event->attr.type == PERF_TYPE_TRACEPOINT);
+#endif
+ }
+
+ return err;
+}
+
+static int __init send_signal_irq_work_init(void)
+{
+ int cpu;
+ struct send_signal_irq_work *work;
+
+ for_each_possible_cpu(cpu) {
+ work = per_cpu_ptr(&send_signal_work, cpu);
+ init_irq_work(&work->irq_work, do_bpf_send_signal);
+ }
+ return 0;
+}
+
+subsys_initcall(send_signal_irq_work_init);
+
+#ifdef CONFIG_MODULES
+static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
+ void *module)
+{
+ struct bpf_trace_module *btm, *tmp;
+ struct module *mod = module;
+ int ret = 0;
+
+ if (mod->num_bpf_raw_events == 0 ||
+ (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
+ goto out;
+
+ mutex_lock(&bpf_module_mutex);
+
+ switch (op) {
+ case MODULE_STATE_COMING:
+ btm = kzalloc(sizeof(*btm), GFP_KERNEL);
+ if (btm) {
+ btm->module = module;
+ list_add(&btm->list, &bpf_trace_modules);
+ } else {
+ ret = -ENOMEM;
+ }
+ break;
+ case MODULE_STATE_GOING:
+ list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
+ if (btm->module == module) {
+ list_del(&btm->list);
+ kfree(btm);
+ break;
+ }
+ }
+ break;
+ }
+
+ mutex_unlock(&bpf_module_mutex);
+
+out:
+ return notifier_from_errno(ret);
+}
+
+static struct notifier_block bpf_module_nb = {
+ .notifier_call = bpf_event_notify,
+};
+
+static int __init bpf_event_init(void)
+{
+ register_module_notifier(&bpf_module_nb);
+ return 0;
+}
+
+fs_initcall(bpf_event_init);
+#endif /* CONFIG_MODULES */