- 根目录:
- arch
- arm64
- kernel
- ptrace.c
/*
* Based on arch/arm/kernel/ptrace.c
*
* By Ross Biro 1/23/92
* edited by Linus Torvalds
* ARM modifications Copyright (C) 2000 Russell King
* Copyright (C) 2012 ARM Ltd.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/audit.h>
#include <linux/compat.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/seccomp.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/tracehook.h>
#include <linux/elf.h>
#include <asm/compat.h>
#include <asm/debug-monitors.h>
#include <asm/pgtable.h>
#include <asm/syscall.h>
#include <asm/traps.h>
#include <asm/system_misc.h>
/*
* TODO: does not yet catch signals sent when the child dies.
* in exit.c or in signal.c.
*/
/*
* Called by kernel/ptrace.c when detaching..
*/
void ptrace_disable(struct task_struct *child)
{
}
#ifdef CONFIG_HAVE_HW_BREAKPOINT
/*
* 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);
siginfo_t info = {
.si_signo = SIGTRAP,
.si_errno = 0,
.si_code = TRAP_HWBKPT,
.si_addr = (void __user *)(bkpt->trigger),
};
#ifdef CONFIG_COMPAT
int i;
if (!is_compat_task())
goto send_sig;
for (i = 0; i < ARM_MAX_BRP; ++i) {
if (current->thread.debug.hbp_break[i] == bp) {
info.si_errno = (i << 1) + 1;
break;
}
}
for (i = ARM_MAX_BRP; i < ARM_MAX_HBP_SLOTS && !bp; ++i) {
if (current->thread.debug.hbp_watch[i] == bp) {
info.si_errno = -((i << 1) + 1);
break;
}
}
send_sig:
#endif
force_sig_info(SIGTRAP, &info, current);
}
/*
* 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_BRP; i++) {
if (t->debug.hbp_break[i]) {
unregister_hw_breakpoint(t->debug.hbp_break[i]);
t->debug.hbp_break[i] = NULL;
}
}
for (i = 0; i < ARM_MAX_WRP; i++) {
if (t->debug.hbp_watch[i]) {
unregister_hw_breakpoint(t->debug.hbp_watch[i]);
t->debug.hbp_watch[i] = NULL;
}
}
}
void ptrace_hw_copy_thread(struct task_struct *tsk)
{
memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
}
static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx)
{
struct perf_event *bp = ERR_PTR(-EINVAL);
switch (note_type) {
case NT_ARM_HW_BREAK:
if (idx < ARM_MAX_BRP)
bp = tsk->thread.debug.hbp_break[idx];
break;
case NT_ARM_HW_WATCH:
if (idx < ARM_MAX_WRP)
bp = tsk->thread.debug.hbp_watch[idx];
break;
}
return bp;
}
static int ptrace_hbp_set_event(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx,
struct perf_event *bp)
{
int err = -EINVAL;
switch (note_type) {
case NT_ARM_HW_BREAK:
if (idx < ARM_MAX_BRP) {
tsk->thread.debug.hbp_break[idx] = bp;
err = 0;
}
break;
case NT_ARM_HW_WATCH:
if (idx < ARM_MAX_WRP) {
tsk->thread.debug.hbp_watch[idx] = bp;
err = 0;
}
break;
}
return err;
}
static struct perf_event *ptrace_hbp_create(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx)
{
struct perf_event *bp;
struct perf_event_attr attr;
int err, type;
switch (note_type) {
case NT_ARM_HW_BREAK:
type = HW_BREAKPOINT_X;
break;
case NT_ARM_HW_WATCH:
type = HW_BREAKPOINT_RW;
break;
default:
return ERR_PTR(-EINVAL);
}
ptrace_breakpoint_init(&attr);
/*
* Initialise fields to sane defaults
* (i.e. values that will pass validation).
*/
attr.bp_addr = 0;
attr.bp_len = HW_BREAKPOINT_LEN_4;
attr.bp_type = type;
attr.disabled = 1;
bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk);
if (IS_ERR(bp))
return bp;
err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
if (err)
return ERR_PTR(err);
return bp;
}
static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
struct arch_hw_breakpoint_ctrl ctrl,
struct perf_event_attr *attr)
{
int err, len, type, disabled = !ctrl.enabled;
if (disabled) {
len = 0;
type = HW_BREAKPOINT_EMPTY;
} else {
err = arch_bp_generic_fields(ctrl, &len, &type);
if (err)
return err;
switch (note_type) {
case NT_ARM_HW_BREAK:
if ((type & HW_BREAKPOINT_X) != type)
return -EINVAL;
break;
case NT_ARM_HW_WATCH:
if ((type & HW_BREAKPOINT_RW) != type)
return -EINVAL;
break;
default:
return -EINVAL;
}
}
attr->bp_len = len;
attr->bp_type = type;
attr->disabled = disabled;
return 0;
}
static int ptrace_hbp_get_resource_info(unsigned int note_type, u32 *info)
{
u8 num;
u32 reg = 0;
switch (note_type) {
case NT_ARM_HW_BREAK:
num = hw_breakpoint_slots(TYPE_INST);
break;
case NT_ARM_HW_WATCH:
num = hw_breakpoint_slots(TYPE_DATA);
break;
default:
return -EINVAL;
}
reg |= debug_monitors_arch();
reg <<= 8;
reg |= num;
*info = reg;
return 0;
}
static int ptrace_hbp_get_ctrl(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx,
u32 *ctrl)
{
struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
if (IS_ERR(bp))
return PTR_ERR(bp);
*ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0;
return 0;
}
static int ptrace_hbp_get_addr(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx,
u64 *addr)
{
struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
if (IS_ERR(bp))
return PTR_ERR(bp);
*addr = bp ? bp->attr.bp_addr : 0;
return 0;
}
static struct perf_event *ptrace_hbp_get_initialised_bp(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx)
{
struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
if (!bp)
bp = ptrace_hbp_create(note_type, tsk, idx);
return bp;
}
static int ptrace_hbp_set_ctrl(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx,
u32 uctrl)
{
int err;
struct perf_event *bp;
struct perf_event_attr attr;
struct arch_hw_breakpoint_ctrl ctrl;
bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
if (IS_ERR(bp)) {
err = PTR_ERR(bp);
return err;
}
attr = bp->attr;
decode_ctrl_reg(uctrl, &ctrl);
err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr);
if (err)
return err;
return modify_user_hw_breakpoint(bp, &attr);
}
static int ptrace_hbp_set_addr(unsigned int note_type,
struct task_struct *tsk,
unsigned long idx,
u64 addr)
{
int err;
struct perf_event *bp;
struct perf_event_attr attr;
bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
if (IS_ERR(bp)) {
err = PTR_ERR(bp);
return err;
}
attr = bp->attr;
attr.bp_addr = addr;
err = modify_user_hw_breakpoint(bp, &attr);
return err;
}
#define PTRACE_HBP_ADDR_SZ sizeof(u64)
#define PTRACE_HBP_CTRL_SZ sizeof(u32)
#define PTRACE_HBP_PAD_SZ sizeof(u32)
static int hw_break_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
unsigned int note_type = regset->core_note_type;
int ret, idx = 0, offset, limit;
u32 info, ctrl;
u64 addr;
/* Resource info */
ret = ptrace_hbp_get_resource_info(note_type, &info);
if (ret)
return ret;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &info, 0,
sizeof(info));
if (ret)
return ret;
/* Pad */
offset = offsetof(struct user_hwdebug_state, pad);
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, offset,
offset + PTRACE_HBP_PAD_SZ);
if (ret)
return ret;
/* (address, ctrl) registers */
offset = offsetof(struct user_hwdebug_state, dbg_regs);
limit = regset->n * regset->size;
while (count && offset < limit) {
ret = ptrace_hbp_get_addr(note_type, target, idx, &addr);
if (ret)
return ret;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &addr,
offset, offset + PTRACE_HBP_ADDR_SZ);
if (ret)
return ret;
offset += PTRACE_HBP_ADDR_SZ;
ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl);
if (ret)
return ret;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &ctrl,
offset, offset + PTRACE_HBP_CTRL_SZ);
if (ret)
return ret;
offset += PTRACE_HBP_CTRL_SZ;
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
offset,
offset + PTRACE_HBP_PAD_SZ);
if (ret)
return ret;
offset += PTRACE_HBP_PAD_SZ;
idx++;
}
return 0;
}
static int hw_break_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
unsigned int note_type = regset->core_note_type;
int ret, idx = 0, offset, limit;
u32 ctrl;
u64 addr;
/* Resource info and pad */
offset = offsetof(struct user_hwdebug_state, dbg_regs);
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
if (ret)
return ret;
/* (address, ctrl) registers */
limit = regset->n * regset->size;
while (count && offset < limit) {
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
offset, offset + PTRACE_HBP_ADDR_SZ);
if (ret)
return ret;
ret = ptrace_hbp_set_addr(note_type, target, idx, addr);
if (ret)
return ret;
offset += PTRACE_HBP_ADDR_SZ;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl,
offset, offset + PTRACE_HBP_CTRL_SZ);
if (ret)
return ret;
ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl);
if (ret)
return ret;
offset += PTRACE_HBP_CTRL_SZ;
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
offset,
offset + PTRACE_HBP_PAD_SZ);
if (ret)
return ret;
offset += PTRACE_HBP_PAD_SZ;
idx++;
}
return 0;
}
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
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 user_pt_regs *uregs = &task_pt_regs(target)->user_regs;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0, -1);
}
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 user_pt_regs newregs;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1);
if (ret)
return ret;
if (!valid_user_regs(&newregs))
return -EINVAL;
task_pt_regs(target)->user_regs = newregs;
return 0;
}
/*
* TODO: update fp accessors for lazy context switching (sync/flush hwstate)
*/
static int fpr_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
struct user_fpsimd_state *uregs;
uregs = &target->thread.fpsimd_state.user_fpsimd;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0, -1);
}
static int fpr_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 user_fpsimd_state newstate;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newstate, 0, -1);
if (ret)
return ret;
target->thread.fpsimd_state.user_fpsimd = newstate;
fpsimd_flush_task_state(target);
return ret;
}
static int tls_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
unsigned long *tls = &target->thread.tp_value;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, tls, 0, -1);
}
static int tls_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;
unsigned long tls;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &tls, 0, -1);
if (ret)
return ret;
target->thread.tp_value = tls;
return ret;
}
enum aarch64_regset {
REGSET_GPR,
REGSET_FPR,
REGSET_TLS,
#ifdef CONFIG_HAVE_HW_BREAKPOINT
REGSET_HW_BREAK,
REGSET_HW_WATCH,
#endif
};
static const struct user_regset aarch64_regsets[] = {
[REGSET_GPR] = {
.core_note_type = NT_PRSTATUS,
.n = sizeof(struct user_pt_regs) / sizeof(u64),
.size = sizeof(u64),
.align = sizeof(u64),
.get = gpr_get,
.set = gpr_set
},
[REGSET_FPR] = {
.core_note_type = NT_PRFPREG,
.n = sizeof(struct user_fpsimd_state) / sizeof(u32),
/*
* We pretend we have 32-bit registers because the fpsr and
* fpcr are 32-bits wide.
*/
.size = sizeof(u32),
.align = sizeof(u32),
.get = fpr_get,
.set = fpr_set
},
[REGSET_TLS] = {
.core_note_type = NT_ARM_TLS,
.n = 1,
.size = sizeof(void *),
.align = sizeof(void *),
.get = tls_get,
.set = tls_set,
},
#ifdef CONFIG_HAVE_HW_BREAKPOINT
[REGSET_HW_BREAK] = {
.core_note_type = NT_ARM_HW_BREAK,
.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
.size = sizeof(u32),
.align = sizeof(u32),
.get = hw_break_get,
.set = hw_break_set,
},
[REGSET_HW_WATCH] = {
.core_note_type = NT_ARM_HW_WATCH,
.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
.size = sizeof(u32),
.align = sizeof(u32),
.get = hw_break_get,
.set = hw_break_set,
},
#endif
};
static const struct user_regset_view user_aarch64_view = {
.name = "aarch64", .e_machine = EM_AARCH64,
.regsets = aarch64_regsets, .n = ARRAY_SIZE(aarch64_regsets)
};
#ifdef CONFIG_COMPAT
#include <linux/compat.h>
enum compat_regset {
REGSET_COMPAT_GPR,
REGSET_COMPAT_VFP,
};
static int compat_gpr_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
int ret = 0;
unsigned int i, start, num_regs;
/* Calculate the number of AArch32 registers contained in count */
num_regs = count / regset->size;
/* Convert pos into an register number */
start = pos / regset->size;
if (start + num_regs > regset->n)
return -EIO;
for (i = 0; i < num_regs; ++i) {
unsigned int idx = start + i;
void *reg;
switch (idx) {
case 15:
reg = (void *)&task_pt_regs(target)->pc;
break;
case 16:
reg = (void *)&task_pt_regs(target)->pstate;
break;
case 17:
reg = (void *)&task_pt_regs(target)->orig_x0;
break;
default:
reg = (void *)&task_pt_regs(target)->regs[idx];
}
ret = copy_to_user(ubuf, reg, sizeof(compat_ulong_t));
if (ret)
break;
else
ubuf += sizeof(compat_ulong_t);
}
return ret;
}
static int compat_gpr_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct pt_regs newregs;
int ret = 0;
unsigned int i, start, num_regs;
/* Calculate the number of AArch32 registers contained in count */
num_regs = count / regset->size;
/* Convert pos into an register number */
start = pos / regset->size;
if (start + num_regs > regset->n)
return -EIO;
newregs = *task_pt_regs(target);
for (i = 0; i < num_regs; ++i) {
unsigned int idx = start + i;
void *reg;
switch (idx) {
case 15:
reg = (void *)&newregs.pc;
break;
case 16:
reg = (void *)&newregs.pstate;
break;
case 17:
reg = (void *)&newregs.orig_x0;
break;
default:
reg = (void *)&newregs.regs[idx];
}
ret = copy_from_user(reg, ubuf, sizeof(compat_ulong_t));
if (ret)
goto out;
else
ubuf += sizeof(compat_ulong_t);
}
if (valid_user_regs(&newregs.user_regs))
*task_pt_regs(target) = newregs;
else
ret = -EINVAL;
out:
return ret;
}
static int compat_vfp_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
struct user_fpsimd_state *uregs;
compat_ulong_t fpscr;
int ret;
uregs = &target->thread.fpsimd_state.user_fpsimd;
/*
* The VFP registers are packed into the fpsimd_state, so they all sit
* nicely together for us. We just need to create the fpscr separately.
*/
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
VFP_STATE_SIZE - sizeof(compat_ulong_t));
if (count && !ret) {
fpscr = (uregs->fpsr & VFP_FPSCR_STAT_MASK) |
(uregs->fpcr & VFP_FPSCR_CTRL_MASK);
ret = put_user(fpscr, (compat_ulong_t *)ubuf);
}
return ret;
}
static int compat_vfp_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct user_fpsimd_state *uregs;
compat_ulong_t fpscr;
int ret;
if (pos + count > VFP_STATE_SIZE)
return -EIO;
uregs = &target->thread.fpsimd_state.user_fpsimd;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
VFP_STATE_SIZE - sizeof(compat_ulong_t));
if (count && !ret) {
ret = get_user(fpscr, (compat_ulong_t *)ubuf);
uregs->fpsr = fpscr & VFP_FPSCR_STAT_MASK;
uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
}
fpsimd_flush_task_state(target);
return ret;
}
static const struct user_regset aarch32_regsets[] = {
[REGSET_COMPAT_GPR] = {
.core_note_type = NT_PRSTATUS,
.n = COMPAT_ELF_NGREG,
.size = sizeof(compat_elf_greg_t),
.align = sizeof(compat_elf_greg_t),
.get = compat_gpr_get,
.set = compat_gpr_set
},
[REGSET_COMPAT_VFP] = {
.core_note_type = NT_ARM_VFP,
.n = VFP_STATE_SIZE / sizeof(compat_ulong_t),
.size = sizeof(compat_ulong_t),
.align = sizeof(compat_ulong_t),
.get = compat_vfp_get,
.set = compat_vfp_set
},
};
static const struct user_regset_view user_aarch32_view = {
.name = "aarch32", .e_machine = EM_ARM,
.regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
};
static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
compat_ulong_t __user *ret)
{
compat_ulong_t tmp;
if (off & 3)
return -EIO;
if (off == COMPAT_PT_TEXT_ADDR)
tmp = tsk->mm->start_code;
else if (off == COMPAT_PT_DATA_ADDR)
tmp = tsk->mm->start_data;
else if (off == COMPAT_PT_TEXT_END_ADDR)
tmp = tsk->mm->end_code;
else if (off < sizeof(compat_elf_gregset_t))
return copy_regset_to_user(tsk, &user_aarch32_view,
REGSET_COMPAT_GPR, off,
sizeof(compat_ulong_t), ret);
else if (off >= COMPAT_USER_SZ)
return -EIO;
else
tmp = 0;
return put_user(tmp, ret);
}
static int compat_ptrace_write_user(struct task_struct *tsk, compat_ulong_t off,
compat_ulong_t val)
{
int ret;
if (off & 3 || off >= COMPAT_USER_SZ)
return -EIO;
if (off >= sizeof(compat_elf_gregset_t))
return 0;
ret = copy_regset_from_user(tsk, &user_aarch32_view,
REGSET_COMPAT_GPR, off,
sizeof(compat_ulong_t),
&val);
return ret;
}
#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 compat_ptrace_hbp_num_to_idx(compat_long_t num)
{
return (abs(num) - 1) >> 1;
}
static int compat_ptrace_hbp_get_resource_info(u32 *kdata)
{
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 = debug_monitors_arch();
wp_len = 8;
reg |= debug_arch;
reg <<= 8;
reg |= wp_len;
reg <<= 8;
reg |= num_wrps;
reg <<= 8;
reg |= num_brps;
*kdata = reg;
return 0;
}
static int compat_ptrace_hbp_get(unsigned int note_type,
struct task_struct *tsk,
compat_long_t num,
u32 *kdata)
{
u64 addr = 0;
u32 ctrl = 0;
int err, idx = compat_ptrace_hbp_num_to_idx(num);;
if (num & 1) {
err = ptrace_hbp_get_addr(note_type, tsk, idx, &addr);
*kdata = (u32)addr;
} else {
err = ptrace_hbp_get_ctrl(note_type, tsk, idx, &ctrl);
*kdata = ctrl;
}
return err;
}
static int compat_ptrace_hbp_set(unsigned int note_type,
struct task_struct *tsk,
compat_long_t num,
u32 *kdata)
{
u64 addr;
u32 ctrl;
int err, idx = compat_ptrace_hbp_num_to_idx(num);
if (num & 1) {
addr = *kdata;
err = ptrace_hbp_set_addr(note_type, tsk, idx, addr);
} else {
ctrl = *kdata;
err = ptrace_hbp_set_ctrl(note_type, tsk, idx, ctrl);
}
return err;
}
static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
compat_ulong_t __user *data)
{
int ret;
u32 kdata;
mm_segment_t old_fs = get_fs();
set_fs(KERNEL_DS);
/* Watchpoint */
if (num < 0) {
ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
/* Resource info */
} else if (num == 0) {
ret = compat_ptrace_hbp_get_resource_info(&kdata);
/* Breakpoint */
} else {
ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
}
set_fs(old_fs);
if (!ret)
ret = put_user(kdata, data);
return ret;
}
static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
compat_ulong_t __user *data)
{
int ret;
u32 kdata = 0;
mm_segment_t old_fs = get_fs();
if (num == 0)
return 0;
ret = get_user(kdata, data);
if (ret)
return ret;
set_fs(KERNEL_DS);
if (num < 0)
ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
else
ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
set_fs(old_fs);
return ret;
}
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
compat_ulong_t caddr, compat_ulong_t cdata)
{
unsigned long addr = caddr;
unsigned long data = cdata;
void __user *datap = compat_ptr(data);
int ret;
switch (request) {
case PTRACE_PEEKUSR:
ret = compat_ptrace_read_user(child, addr, datap);
break;
case PTRACE_POKEUSR:
ret = compat_ptrace_write_user(child, addr, data);
break;
case COMPAT_PTRACE_GETREGS:
ret = copy_regset_to_user(child,
&user_aarch32_view,
REGSET_COMPAT_GPR,
0, sizeof(compat_elf_gregset_t),
datap);
break;
case COMPAT_PTRACE_SETREGS:
ret = copy_regset_from_user(child,
&user_aarch32_view,
REGSET_COMPAT_GPR,
0, sizeof(compat_elf_gregset_t),
datap);
break;
case COMPAT_PTRACE_GET_THREAD_AREA:
ret = put_user((compat_ulong_t)child->thread.tp_value,
(compat_ulong_t __user *)datap);
break;
case COMPAT_PTRACE_SET_SYSCALL:
task_pt_regs(child)->syscallno = data;
ret = 0;
break;
case COMPAT_PTRACE_GETVFPREGS:
ret = copy_regset_to_user(child,
&user_aarch32_view,
REGSET_COMPAT_VFP,
0, VFP_STATE_SIZE,
datap);
break;
case COMPAT_PTRACE_SETVFPREGS:
ret = copy_regset_from_user(child,
&user_aarch32_view,
REGSET_COMPAT_VFP,
0, VFP_STATE_SIZE,
datap);
break;
#ifdef CONFIG_HAVE_HW_BREAKPOINT
case COMPAT_PTRACE_GETHBPREGS:
ret = compat_ptrace_gethbpregs(child, addr, datap);
break;
case COMPAT_PTRACE_SETHBPREGS:
ret = compat_ptrace_sethbpregs(child, addr, datap);
break;
#endif
default:
ret = compat_ptrace_request(child, request, addr,
data);
break;
}
return ret;
}
#endif /* CONFIG_COMPAT */
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
#ifdef CONFIG_COMPAT
if (is_compat_thread(task_thread_info(task)))
return &user_aarch32_view;
#endif
return &user_aarch64_view;
}
long arch_ptrace(struct task_struct *child, long request,
unsigned long addr, unsigned long data)
{
int ret;
switch (request) {
case PTRACE_SET_SYSCALL:
task_pt_regs(child)->syscallno = data;
ret = 0;
break;
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)
{
int regno;
unsigned long saved_reg;
/*
* A scratch register (ip(r12) on AArch32, x7 on AArch64) is
* used to denote syscall entry/exit:
*/
regno = (is_compat_task() ? 12 : 7);
saved_reg = regs->regs[regno];
regs->regs[regno] = dir;
if (dir == PTRACE_SYSCALL_EXIT)
tracehook_report_syscall_exit(regs, 0);
else if (tracehook_report_syscall_entry(regs))
regs->syscallno = ~0UL;
regs->regs[regno] = saved_reg;
}
asmlinkage int syscall_trace_enter(struct pt_regs *regs)
{
unsigned int saved_syscallno = regs->syscallno;
/* Do the secure computing check first; failures should be fast. */
if (secure_computing(regs->syscallno) == -1)
return RET_SKIP_SYSCALL_TRACE;
if (test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
if (IS_SKIP_SYSCALL(regs->syscallno)) {
/*
* RESTRICTION: we can't modify a return value of user
* issued syscall(-1) here. In order to ease this flavor,
* we need to treat whatever value in x0 as a return value,
* but this might result in a bogus value being returned.
*/
/*
* NOTE: syscallno may also be set to -1 if fatal signal is
* detected in tracehook_report_syscall_entry(), but since
* a value set to x0 here is not used in this case, we may
* neglect the case.
*/
if (!test_thread_flag(TIF_SYSCALL_TRACE) ||
(IS_SKIP_SYSCALL(saved_syscallno)))
regs->regs[0] = -ENOSYS;
}
audit_syscall_entry(syscall_get_arch(), regs->syscallno,
regs->orig_x0, regs->regs[1], regs->regs[2], regs->regs[3]);
return regs->syscallno;
}
asmlinkage void syscall_trace_exit(struct pt_regs *regs)
{
audit_syscall_exit(regs);
if (test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
}