linux/arch/arm/kernel/ptrace.c
Will Deacon b10bca0bc6 ARM: 7595/1: syscall: rework ordering in syscall_trace_exit
syscall_trace_exit is currently doing things back-to-front; invoking
the audit hook *after* signalling the debugger, which presents an
opportunity for the registers to be re-written by userspace in order to
bypass auditing constaints.

This patch fixes the ordering by moving the audit code first and the
tracehook code last. On the face of it, it looks like
current_thread_info()->syscall may be incorrect for the sys_exit
tracepoint, but that's actually not an issue because it will have been
set during syscall entry and cannot have changed since then.

Reported-by: Andrew Gabbasov <Andrew_Gabbasov@mentor.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-12-11 00:18:26 +00:00

980 lines
23 KiB
C

/*
* linux/arch/arm/kernel/ptrace.c
*
* By Ross Biro 1/23/92
* edited by Linus Torvalds
* ARM modifications Copyright (C) 2000 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/sched.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/pgtable.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 task_struct *tsk, struct pt_regs *regs)
{
siginfo_t info;
info.si_signo = SIGTRAP;
info.si_errno = 0;
info.si_code = TRAP_BRKPT;
info.si_addr = (void __user *)instruction_pointer(regs);
force_sig_info(SIGTRAP, &info, tsk);
}
static int break_trap(struct pt_regs *regs, unsigned int instr)
{
ptrace_break(current, 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 = 0xffff,
.instr_val = 0xde01,
.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;
siginfo_t info;
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);
info.si_signo = SIGTRAP;
info.si_errno = (int)num;
info.si_code = TRAP_HWBKPT;
info.si_addr = (void __user *)(bkpt->trigger);
force_sig_info(SIGTRAP, &info, current);
}
/*
* 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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
struct pt_regs *regs = task_pt_regs(target);
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
regs,
0, sizeof(*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;
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,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&task_thread_info(target)->fpstate,
0, 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
*
* The bounds-checking logic built into user_regset_copyout and friends
* means that we can make a simple sequence of calls to map the relevant data
* to/from the specified slice of the user regset structure.
*/
static int vfp_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
int ret;
struct thread_info *thread = task_thread_info(target);
struct vfp_hard_struct const *vfp = &thread->vfpstate.hard;
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);
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&vfp->fpregs,
user_fpregs_offset,
user_fpregs_offset + sizeof(vfp->fpregs));
if (ret)
return ret;
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
user_fpregs_offset + sizeof(vfp->fpregs),
user_fpscr_offset);
if (ret)
return ret;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&vfp->fpscr,
user_fpscr_offset,
user_fpscr_offset + sizeof(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;
vfp_flush_hwstate(thread);
thread->vfpstate.hard = new_vfp;
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),
.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),
.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),
.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,
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:
if (ptrace_get_breakpoints(child) < 0)
return -ESRCH;
ret = ptrace_gethbpregs(child, addr,
(unsigned long __user *)data);
ptrace_put_breakpoints(child);
break;
case PTRACE_SETHBPREGS:
if (ptrace_get_breakpoints(child) < 0)
return -ESRCH;
ret = ptrace_sethbpregs(child, addr,
(unsigned long __user *)data);
ptrace_put_breakpoints(child);
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 int 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;
return current_thread_info()->syscall;
}
asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
{
current_thread_info()->syscall = scno;
/* Do the secure computing check first; failures should be fast. */
if (secure_computing(scno) == -1)
return -1;
if (test_thread_flag(TIF_SYSCALL_TRACE))
scno = tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
trace_sys_enter(regs, scno);
audit_syscall_entry(AUDIT_ARCH_ARM, 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);
}