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-rw-r--r--arch/arm/kernel/ptrace.c935
1 files changed, 935 insertions, 0 deletions
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
new file mode 100644
index 000000000..2771e6822
--- /dev/null
+++ b/arch/arm/kernel/ptrace.c
@@ -0,0 +1,935 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/arch/arm/kernel/ptrace.c
+ *
+ * By Ross Biro 1/23/92
+ * edited by Linus Torvalds
+ * ARM modifications Copyright (C) 2000 Russell King
+ */
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/task_stack.h>
+#include <linux/mm.h>
+#include <linux/elf.h>
+#include <linux/smp.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/security.h>
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/uaccess.h>
+#include <linux/perf_event.h>
+#include <linux/hw_breakpoint.h>
+#include <linux/regset.h>
+#include <linux/audit.h>
+#include <linux/tracehook.h>
+#include <linux/unistd.h>
+
+#include <asm/traps.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
+#define REG_PC 15
+#define REG_PSR 16
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+#if 0
+/*
+ * Breakpoint SWI instruction: SWI &9F0001
+ */
+#define BREAKINST_ARM 0xef9f0001
+#define BREAKINST_THUMB 0xdf00 /* fill this in later */
+#else
+/*
+ * New breakpoints - use an undefined instruction. The ARM architecture
+ * reference manual guarantees that the following instruction space
+ * will produce an undefined instruction exception on all CPUs:
+ *
+ * ARM: xxxx 0111 1111 xxxx xxxx xxxx 1111 xxxx
+ * Thumb: 1101 1110 xxxx xxxx
+ */
+#define BREAKINST_ARM 0xe7f001f0
+#define BREAKINST_THUMB 0xde01
+#endif
+
+struct pt_regs_offset {
+ const char *name;
+ int offset;
+};
+
+#define REG_OFFSET_NAME(r) \
+ {.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)}
+#define REG_OFFSET_END {.name = NULL, .offset = 0}
+
+static const struct pt_regs_offset regoffset_table[] = {
+ REG_OFFSET_NAME(r0),
+ REG_OFFSET_NAME(r1),
+ REG_OFFSET_NAME(r2),
+ REG_OFFSET_NAME(r3),
+ REG_OFFSET_NAME(r4),
+ REG_OFFSET_NAME(r5),
+ REG_OFFSET_NAME(r6),
+ REG_OFFSET_NAME(r7),
+ REG_OFFSET_NAME(r8),
+ REG_OFFSET_NAME(r9),
+ REG_OFFSET_NAME(r10),
+ REG_OFFSET_NAME(fp),
+ REG_OFFSET_NAME(ip),
+ REG_OFFSET_NAME(sp),
+ REG_OFFSET_NAME(lr),
+ REG_OFFSET_NAME(pc),
+ REG_OFFSET_NAME(cpsr),
+ REG_OFFSET_NAME(ORIG_r0),
+ REG_OFFSET_END,
+};
+
+/**
+ * regs_query_register_offset() - query register offset from its name
+ * @name: the name of a register
+ *
+ * regs_query_register_offset() returns the offset of a register in struct
+ * pt_regs from its name. If the name is invalid, this returns -EINVAL;
+ */
+int regs_query_register_offset(const char *name)
+{
+ const struct pt_regs_offset *roff;
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (!strcmp(roff->name, name))
+ return roff->offset;
+ return -EINVAL;
+}
+
+/**
+ * regs_query_register_name() - query register name from its offset
+ * @offset: the offset of a register in struct pt_regs.
+ *
+ * regs_query_register_name() returns the name of a register from its
+ * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
+ */
+const char *regs_query_register_name(unsigned int offset)
+{
+ const struct pt_regs_offset *roff;
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (roff->offset == offset)
+ return roff->name;
+ return NULL;
+}
+
+/**
+ * regs_within_kernel_stack() - check the address in the stack
+ * @regs: pt_regs which contains kernel stack pointer.
+ * @addr: address which is checked.
+ *
+ * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
+ * If @addr is within the kernel stack, it returns true. If not, returns false.
+ */
+bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
+{
+ return ((addr & ~(THREAD_SIZE - 1)) ==
+ (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
+}
+
+/**
+ * regs_get_kernel_stack_nth() - get Nth entry of the stack
+ * @regs: pt_regs which contains kernel stack pointer.
+ * @n: stack entry number.
+ *
+ * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
+ * is specified by @regs. If the @n th entry is NOT in the kernel stack,
+ * this returns 0.
+ */
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+ unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
+ addr += n;
+ if (regs_within_kernel_stack(regs, (unsigned long)addr))
+ return *addr;
+ else
+ return 0;
+}
+
+/*
+ * this routine will get a word off of the processes privileged stack.
+ * the offset is how far from the base addr as stored in the THREAD.
+ * this routine assumes that all the privileged stacks are in our
+ * data space.
+ */
+static inline long get_user_reg(struct task_struct *task, int offset)
+{
+ return task_pt_regs(task)->uregs[offset];
+}
+
+/*
+ * this routine will put a word on the processes privileged stack.
+ * the offset is how far from the base addr as stored in the THREAD.
+ * this routine assumes that all the privileged stacks are in our
+ * data space.
+ */
+static inline int
+put_user_reg(struct task_struct *task, int offset, long data)
+{
+ struct pt_regs newregs, *regs = task_pt_regs(task);
+ int ret = -EINVAL;
+
+ newregs = *regs;
+ newregs.uregs[offset] = data;
+
+ if (valid_user_regs(&newregs)) {
+ regs->uregs[offset] = data;
+ ret = 0;
+ }
+
+ return ret;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ /* Nothing to do. */
+}
+
+/*
+ * Handle hitting a breakpoint.
+ */
+void ptrace_break(struct pt_regs *regs)
+{
+ force_sig_fault(SIGTRAP, TRAP_BRKPT,
+ (void __user *)instruction_pointer(regs));
+}
+
+static int break_trap(struct pt_regs *regs, unsigned int instr)
+{
+ ptrace_break(regs);
+ return 0;
+}
+
+static struct undef_hook arm_break_hook = {
+ .instr_mask = 0x0fffffff,
+ .instr_val = 0x07f001f0,
+ .cpsr_mask = PSR_T_BIT,
+ .cpsr_val = 0,
+ .fn = break_trap,
+};
+
+static struct undef_hook thumb_break_hook = {
+ .instr_mask = 0xffffffff,
+ .instr_val = 0x0000de01,
+ .cpsr_mask = PSR_T_BIT,
+ .cpsr_val = PSR_T_BIT,
+ .fn = break_trap,
+};
+
+static struct undef_hook thumb2_break_hook = {
+ .instr_mask = 0xffffffff,
+ .instr_val = 0xf7f0a000,
+ .cpsr_mask = PSR_T_BIT,
+ .cpsr_val = PSR_T_BIT,
+ .fn = break_trap,
+};
+
+static int __init ptrace_break_init(void)
+{
+ register_undef_hook(&arm_break_hook);
+ register_undef_hook(&thumb_break_hook);
+ register_undef_hook(&thumb2_break_hook);
+ return 0;
+}
+
+core_initcall(ptrace_break_init);
+
+/*
+ * Read the word at offset "off" into the "struct user". We
+ * actually access the pt_regs stored on the kernel stack.
+ */
+static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
+ unsigned long __user *ret)
+{
+ unsigned long tmp;
+
+ if (off & 3)
+ return -EIO;
+
+ tmp = 0;
+ if (off == PT_TEXT_ADDR)
+ tmp = tsk->mm->start_code;
+ else if (off == PT_DATA_ADDR)
+ tmp = tsk->mm->start_data;
+ else if (off == PT_TEXT_END_ADDR)
+ tmp = tsk->mm->end_code;
+ else if (off < sizeof(struct pt_regs))
+ tmp = get_user_reg(tsk, off >> 2);
+ else if (off >= sizeof(struct user))
+ return -EIO;
+
+ return put_user(tmp, ret);
+}
+
+/*
+ * Write the word at offset "off" into "struct user". We
+ * actually access the pt_regs stored on the kernel stack.
+ */
+static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
+ unsigned long val)
+{
+ if (off & 3 || off >= sizeof(struct user))
+ return -EIO;
+
+ if (off >= sizeof(struct pt_regs))
+ return 0;
+
+ return put_user_reg(tsk, off >> 2, val);
+}
+
+#ifdef CONFIG_IWMMXT
+
+/*
+ * Get the child iWMMXt state.
+ */
+static int ptrace_getwmmxregs(struct task_struct *tsk, void __user *ufp)
+{
+ struct thread_info *thread = task_thread_info(tsk);
+
+ if (!test_ti_thread_flag(thread, TIF_USING_IWMMXT))
+ return -ENODATA;
+ iwmmxt_task_disable(thread); /* force it to ram */
+ return copy_to_user(ufp, &thread->fpstate.iwmmxt, IWMMXT_SIZE)
+ ? -EFAULT : 0;
+}
+
+/*
+ * Set the child iWMMXt state.
+ */
+static int ptrace_setwmmxregs(struct task_struct *tsk, void __user *ufp)
+{
+ struct thread_info *thread = task_thread_info(tsk);
+
+ if (!test_ti_thread_flag(thread, TIF_USING_IWMMXT))
+ return -EACCES;
+ iwmmxt_task_release(thread); /* force a reload */
+ return copy_from_user(&thread->fpstate.iwmmxt, ufp, IWMMXT_SIZE)
+ ? -EFAULT : 0;
+}
+
+#endif
+
+#ifdef CONFIG_CRUNCH
+/*
+ * Get the child Crunch state.
+ */
+static int ptrace_getcrunchregs(struct task_struct *tsk, void __user *ufp)
+{
+ struct thread_info *thread = task_thread_info(tsk);
+
+ crunch_task_disable(thread); /* force it to ram */
+ return copy_to_user(ufp, &thread->crunchstate, CRUNCH_SIZE)
+ ? -EFAULT : 0;
+}
+
+/*
+ * Set the child Crunch state.
+ */
+static int ptrace_setcrunchregs(struct task_struct *tsk, void __user *ufp)
+{
+ struct thread_info *thread = task_thread_info(tsk);
+
+ crunch_task_release(thread); /* force a reload */
+ return copy_from_user(&thread->crunchstate, ufp, CRUNCH_SIZE)
+ ? -EFAULT : 0;
+}
+#endif
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+/*
+ * Convert a virtual register number into an index for a thread_info
+ * breakpoint array. Breakpoints are identified using positive numbers
+ * whilst watchpoints are negative. The registers are laid out as pairs
+ * of (address, control), each pair mapping to a unique hw_breakpoint struct.
+ * Register 0 is reserved for describing resource information.
+ */
+static int ptrace_hbp_num_to_idx(long num)
+{
+ if (num < 0)
+ num = (ARM_MAX_BRP << 1) - num;
+ return (num - 1) >> 1;
+}
+
+/*
+ * Returns the virtual register number for the address of the
+ * breakpoint at index idx.
+ */
+static long ptrace_hbp_idx_to_num(int idx)
+{
+ long mid = ARM_MAX_BRP << 1;
+ long num = (idx << 1) + 1;
+ return num > mid ? mid - num : num;
+}
+
+/*
+ * Handle hitting a HW-breakpoint.
+ */
+static void ptrace_hbptriggered(struct perf_event *bp,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
+ long num;
+ int i;
+
+ for (i = 0; i < ARM_MAX_HBP_SLOTS; ++i)
+ if (current->thread.debug.hbp[i] == bp)
+ break;
+
+ num = (i == ARM_MAX_HBP_SLOTS) ? 0 : ptrace_hbp_idx_to_num(i);
+
+ force_sig_ptrace_errno_trap((int)num, (void __user *)(bkpt->trigger));
+}
+
+/*
+ * Set ptrace breakpoint pointers to zero for this task.
+ * This is required in order to prevent child processes from unregistering
+ * breakpoints held by their parent.
+ */
+void clear_ptrace_hw_breakpoint(struct task_struct *tsk)
+{
+ memset(tsk->thread.debug.hbp, 0, sizeof(tsk->thread.debug.hbp));
+}
+
+/*
+ * Unregister breakpoints from this task and reset the pointers in
+ * the thread_struct.
+ */
+void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
+{
+ int i;
+ struct thread_struct *t = &tsk->thread;
+
+ for (i = 0; i < ARM_MAX_HBP_SLOTS; i++) {
+ if (t->debug.hbp[i]) {
+ unregister_hw_breakpoint(t->debug.hbp[i]);
+ t->debug.hbp[i] = NULL;
+ }
+ }
+}
+
+static u32 ptrace_get_hbp_resource_info(void)
+{
+ u8 num_brps, num_wrps, debug_arch, wp_len;
+ u32 reg = 0;
+
+ num_brps = hw_breakpoint_slots(TYPE_INST);
+ num_wrps = hw_breakpoint_slots(TYPE_DATA);
+ debug_arch = arch_get_debug_arch();
+ wp_len = arch_get_max_wp_len();
+
+ reg |= debug_arch;
+ reg <<= 8;
+ reg |= wp_len;
+ reg <<= 8;
+ reg |= num_wrps;
+ reg <<= 8;
+ reg |= num_brps;
+
+ return reg;
+}
+
+static struct perf_event *ptrace_hbp_create(struct task_struct *tsk, int type)
+{
+ struct perf_event_attr attr;
+
+ ptrace_breakpoint_init(&attr);
+
+ /* Initialise fields to sane defaults. */
+ attr.bp_addr = 0;
+ attr.bp_len = HW_BREAKPOINT_LEN_4;
+ attr.bp_type = type;
+ attr.disabled = 1;
+
+ return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL,
+ tsk);
+}
+
+static int ptrace_gethbpregs(struct task_struct *tsk, long num,
+ unsigned long __user *data)
+{
+ u32 reg;
+ int idx, ret = 0;
+ struct perf_event *bp;
+ struct arch_hw_breakpoint_ctrl arch_ctrl;
+
+ if (num == 0) {
+ reg = ptrace_get_hbp_resource_info();
+ } else {
+ idx = ptrace_hbp_num_to_idx(num);
+ if (idx < 0 || idx >= ARM_MAX_HBP_SLOTS) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ bp = tsk->thread.debug.hbp[idx];
+ if (!bp) {
+ reg = 0;
+ goto put;
+ }
+
+ arch_ctrl = counter_arch_bp(bp)->ctrl;
+
+ /*
+ * Fix up the len because we may have adjusted it
+ * to compensate for an unaligned address.
+ */
+ while (!(arch_ctrl.len & 0x1))
+ arch_ctrl.len >>= 1;
+
+ if (num & 0x1)
+ reg = bp->attr.bp_addr;
+ else
+ reg = encode_ctrl_reg(arch_ctrl);
+ }
+
+put:
+ if (put_user(reg, data))
+ ret = -EFAULT;
+
+out:
+ return ret;
+}
+
+static int ptrace_sethbpregs(struct task_struct *tsk, long num,
+ unsigned long __user *data)
+{
+ int idx, gen_len, gen_type, implied_type, ret = 0;
+ u32 user_val;
+ struct perf_event *bp;
+ struct arch_hw_breakpoint_ctrl ctrl;
+ struct perf_event_attr attr;
+
+ if (num == 0)
+ goto out;
+ else if (num < 0)
+ implied_type = HW_BREAKPOINT_RW;
+ else
+ implied_type = HW_BREAKPOINT_X;
+
+ idx = ptrace_hbp_num_to_idx(num);
+ if (idx < 0 || idx >= ARM_MAX_HBP_SLOTS) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (get_user(user_val, data)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ bp = tsk->thread.debug.hbp[idx];
+ if (!bp) {
+ bp = ptrace_hbp_create(tsk, implied_type);
+ if (IS_ERR(bp)) {
+ ret = PTR_ERR(bp);
+ goto out;
+ }
+ tsk->thread.debug.hbp[idx] = bp;
+ }
+
+ attr = bp->attr;
+
+ if (num & 0x1) {
+ /* Address */
+ attr.bp_addr = user_val;
+ } else {
+ /* Control */
+ decode_ctrl_reg(user_val, &ctrl);
+ ret = arch_bp_generic_fields(ctrl, &gen_len, &gen_type);
+ if (ret)
+ goto out;
+
+ if ((gen_type & implied_type) != gen_type) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ attr.bp_len = gen_len;
+ attr.bp_type = gen_type;
+ attr.disabled = !ctrl.enabled;
+ }
+
+ ret = modify_user_hw_breakpoint(bp, &attr);
+out:
+ return ret;
+}
+#endif
+
+/* regset get/set implementations */
+
+static int gpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ return membuf_write(&to, task_pt_regs(target), sizeof(struct pt_regs));
+}
+
+static int gpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct pt_regs newregs = *task_pt_regs(target);
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &newregs,
+ 0, sizeof(newregs));
+ if (ret)
+ return ret;
+
+ if (!valid_user_regs(&newregs))
+ return -EINVAL;
+
+ *task_pt_regs(target) = newregs;
+ return 0;
+}
+
+static int fpa_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ return membuf_write(&to, &task_thread_info(target)->fpstate,
+ sizeof(struct user_fp));
+}
+
+static int fpa_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct thread_info *thread = task_thread_info(target);
+
+ thread->used_cp[1] = thread->used_cp[2] = 1;
+
+ return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &thread->fpstate,
+ 0, sizeof(struct user_fp));
+}
+
+#ifdef CONFIG_VFP
+/*
+ * VFP register get/set implementations.
+ *
+ * With respect to the kernel, struct user_fp is divided into three chunks:
+ * 16 or 32 real VFP registers (d0-d15 or d0-31)
+ * These are transferred to/from the real registers in the task's
+ * vfp_hard_struct. The number of registers depends on the kernel
+ * configuration.
+ *
+ * 16 or 0 fake VFP registers (d16-d31 or empty)
+ * i.e., the user_vfp structure has space for 32 registers even if
+ * the kernel doesn't have them all.
+ *
+ * vfp_get() reads this chunk as zero where applicable
+ * vfp_set() ignores this chunk
+ *
+ * 1 word for the FPSCR
+ */
+static int vfp_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct thread_info *thread = task_thread_info(target);
+ struct vfp_hard_struct const *vfp = &thread->vfpstate.hard;
+ const size_t user_fpscr_offset = offsetof(struct user_vfp, fpscr);
+
+ vfp_sync_hwstate(thread);
+
+ membuf_write(&to, vfp->fpregs, sizeof(vfp->fpregs));
+ membuf_zero(&to, user_fpscr_offset - sizeof(vfp->fpregs));
+ return membuf_store(&to, vfp->fpscr);
+}
+
+/*
+ * For vfp_set() a read-modify-write is done on the VFP registers,
+ * in order to avoid writing back a half-modified set of registers on
+ * failure.
+ */
+static int vfp_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct thread_info *thread = task_thread_info(target);
+ struct vfp_hard_struct new_vfp;
+ const size_t user_fpregs_offset = offsetof(struct user_vfp, fpregs);
+ const size_t user_fpscr_offset = offsetof(struct user_vfp, fpscr);
+
+ vfp_sync_hwstate(thread);
+ new_vfp = thread->vfpstate.hard;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &new_vfp.fpregs,
+ user_fpregs_offset,
+ user_fpregs_offset + sizeof(new_vfp.fpregs));
+ if (ret)
+ return ret;
+
+ ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+ user_fpregs_offset + sizeof(new_vfp.fpregs),
+ user_fpscr_offset);
+ if (ret)
+ return ret;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &new_vfp.fpscr,
+ user_fpscr_offset,
+ user_fpscr_offset + sizeof(new_vfp.fpscr));
+ if (ret)
+ return ret;
+
+ thread->vfpstate.hard = new_vfp;
+ vfp_flush_hwstate(thread);
+
+ return 0;
+}
+#endif /* CONFIG_VFP */
+
+enum arm_regset {
+ REGSET_GPR,
+ REGSET_FPR,
+#ifdef CONFIG_VFP
+ REGSET_VFP,
+#endif
+};
+
+static const struct user_regset arm_regsets[] = {
+ [REGSET_GPR] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = gpr_get,
+ .set = gpr_set
+ },
+ [REGSET_FPR] = {
+ /*
+ * For the FPA regs in fpstate, the real fields are a mixture
+ * of sizes, so pretend that the registers are word-sized:
+ */
+ .core_note_type = NT_PRFPREG,
+ .n = sizeof(struct user_fp) / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = fpa_get,
+ .set = fpa_set
+ },
+#ifdef CONFIG_VFP
+ [REGSET_VFP] = {
+ /*
+ * Pretend that the VFP regs are word-sized, since the FPSCR is
+ * a single word dangling at the end of struct user_vfp:
+ */
+ .core_note_type = NT_ARM_VFP,
+ .n = ARM_VFPREGS_SIZE / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = vfp_get,
+ .set = vfp_set
+ },
+#endif /* CONFIG_VFP */
+};
+
+static const struct user_regset_view user_arm_view = {
+ .name = "arm", .e_machine = ELF_ARCH, .ei_osabi = ELF_OSABI,
+ .regsets = arm_regsets, .n = ARRAY_SIZE(arm_regsets)
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &user_arm_view;
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ int ret;
+ unsigned long __user *datap = (unsigned long __user *) data;
+
+ switch (request) {
+ case PTRACE_PEEKUSR:
+ ret = ptrace_read_user(child, addr, datap);
+ break;
+
+ case PTRACE_POKEUSR:
+ ret = ptrace_write_user(child, addr, data);
+ break;
+
+ case PTRACE_GETREGS:
+ ret = copy_regset_to_user(child,
+ &user_arm_view, REGSET_GPR,
+ 0, sizeof(struct pt_regs),
+ datap);
+ break;
+
+ case PTRACE_SETREGS:
+ ret = copy_regset_from_user(child,
+ &user_arm_view, REGSET_GPR,
+ 0, sizeof(struct pt_regs),
+ datap);
+ break;
+
+ case PTRACE_GETFPREGS:
+ ret = copy_regset_to_user(child,
+ &user_arm_view, REGSET_FPR,
+ 0, sizeof(union fp_state),
+ datap);
+ break;
+
+ case PTRACE_SETFPREGS:
+ ret = copy_regset_from_user(child,
+ &user_arm_view, REGSET_FPR,
+ 0, sizeof(union fp_state),
+ datap);
+ break;
+
+#ifdef CONFIG_IWMMXT
+ case PTRACE_GETWMMXREGS:
+ ret = ptrace_getwmmxregs(child, datap);
+ break;
+
+ case PTRACE_SETWMMXREGS:
+ ret = ptrace_setwmmxregs(child, datap);
+ break;
+#endif
+
+ case PTRACE_GET_THREAD_AREA:
+ ret = put_user(task_thread_info(child)->tp_value[0],
+ datap);
+ break;
+
+ case PTRACE_SET_SYSCALL:
+ task_thread_info(child)->syscall = data;
+ ret = 0;
+ break;
+
+#ifdef CONFIG_CRUNCH
+ case PTRACE_GETCRUNCHREGS:
+ ret = ptrace_getcrunchregs(child, datap);
+ break;
+
+ case PTRACE_SETCRUNCHREGS:
+ ret = ptrace_setcrunchregs(child, datap);
+ break;
+#endif
+
+#ifdef CONFIG_VFP
+ case PTRACE_GETVFPREGS:
+ ret = copy_regset_to_user(child,
+ &user_arm_view, REGSET_VFP,
+ 0, ARM_VFPREGS_SIZE,
+ datap);
+ break;
+
+ case PTRACE_SETVFPREGS:
+ ret = copy_regset_from_user(child,
+ &user_arm_view, REGSET_VFP,
+ 0, ARM_VFPREGS_SIZE,
+ datap);
+ break;
+#endif
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ case PTRACE_GETHBPREGS:
+ ret = ptrace_gethbpregs(child, addr,
+ (unsigned long __user *)data);
+ break;
+ case PTRACE_SETHBPREGS:
+ ret = ptrace_sethbpregs(child, addr,
+ (unsigned long __user *)data);
+ break;
+#endif
+
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+enum ptrace_syscall_dir {
+ PTRACE_SYSCALL_ENTER = 0,
+ PTRACE_SYSCALL_EXIT,
+};
+
+static void tracehook_report_syscall(struct pt_regs *regs,
+ enum ptrace_syscall_dir dir)
+{
+ unsigned long ip;
+
+ /*
+ * IP is used to denote syscall entry/exit:
+ * IP = 0 -> entry, =1 -> exit
+ */
+ ip = regs->ARM_ip;
+ regs->ARM_ip = dir;
+
+ if (dir == PTRACE_SYSCALL_EXIT)
+ tracehook_report_syscall_exit(regs, 0);
+ else if (tracehook_report_syscall_entry(regs))
+ current_thread_info()->syscall = -1;
+
+ regs->ARM_ip = ip;
+}
+
+asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
+{
+ current_thread_info()->syscall = scno;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
+
+ /* Do seccomp after ptrace; syscall may have changed. */
+#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER
+ if (secure_computing() == -1)
+ return -1;
+#else
+ /* XXX: remove this once OABI gets fixed */
+ secure_computing_strict(current_thread_info()->syscall);
+#endif
+
+ /* Tracer or seccomp may have changed syscall. */
+ scno = current_thread_info()->syscall;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, scno);
+
+ audit_syscall_entry(scno, regs->ARM_r0, regs->ARM_r1, regs->ARM_r2,
+ regs->ARM_r3);
+
+ return scno;
+}
+
+asmlinkage void syscall_trace_exit(struct pt_regs *regs)
+{
+ /*
+ * Audit the syscall before anything else, as a debugger may
+ * come in and change the current registers.
+ */
+ audit_syscall_exit(regs);
+
+ /*
+ * Note that we haven't updated the ->syscall field for the
+ * current thread. This isn't a problem because it will have
+ * been set on syscall entry and there hasn't been an opportunity
+ * for a PTRACE_SET_SYSCALL since then.
+ */
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_exit(regs, regs_return_value(regs));
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
+}