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Diffstat (limited to 'arch/x86/kernel/ptrace.c')
-rw-r--r--arch/x86/kernel/ptrace.c135
1 files changed, 69 insertions, 66 deletions
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 04d182a7cfdb..017d937639fe 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -509,14 +509,14 @@ static int genregs_get(struct task_struct *target,
{
if (kbuf) {
unsigned long *k = kbuf;
- while (count > 0) {
+ while (count >= sizeof(*k)) {
*k++ = getreg(target, pos);
count -= sizeof(*k);
pos += sizeof(*k);
}
} else {
unsigned long __user *u = ubuf;
- while (count > 0) {
+ while (count >= sizeof(*u)) {
if (__put_user(getreg(target, pos), u++))
return -EFAULT;
count -= sizeof(*u);
@@ -535,14 +535,14 @@ static int genregs_set(struct task_struct *target,
int ret = 0;
if (kbuf) {
const unsigned long *k = kbuf;
- while (count > 0 && !ret) {
+ while (count >= sizeof(*k) && !ret) {
ret = putreg(target, pos, *k++);
count -= sizeof(*k);
pos += sizeof(*k);
}
} else {
const unsigned long __user *u = ubuf;
- while (count > 0 && !ret) {
+ while (count >= sizeof(*u) && !ret) {
unsigned long word;
ret = __get_user(word, u++);
if (ret)
@@ -555,7 +555,9 @@ static int genregs_set(struct task_struct *target,
return ret;
}
-static void ptrace_triggered(struct perf_event *bp, void *data)
+static void ptrace_triggered(struct perf_event *bp, int nmi,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
{
int i;
struct thread_struct *thread = &(current->thread);
@@ -593,13 +595,13 @@ static unsigned long ptrace_get_dr7(struct perf_event *bp[])
return dr7;
}
-static struct perf_event *
+static int
ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
struct task_struct *tsk, int disabled)
{
int err;
int gen_len, gen_type;
- DEFINE_BREAKPOINT_ATTR(attr);
+ struct perf_event_attr attr;
/*
* We shoud have at least an inactive breakpoint at this
@@ -607,18 +609,18 @@ ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
* written the address register first
*/
if (!bp)
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
err = arch_bp_generic_fields(len, type, &gen_len, &gen_type);
if (err)
- return ERR_PTR(err);
+ return err;
attr = bp->attr;
attr.bp_len = gen_len;
attr.bp_type = gen_type;
attr.disabled = disabled;
- return modify_user_hw_breakpoint(bp, &attr, bp->callback, tsk);
+ return modify_user_hw_breakpoint(bp, &attr);
}
/*
@@ -656,28 +658,17 @@ restore:
if (!second_pass)
continue;
- thread->ptrace_bps[i] = NULL;
- bp = ptrace_modify_breakpoint(bp, len, type,
+ rc = ptrace_modify_breakpoint(bp, len, type,
tsk, 1);
- if (IS_ERR(bp)) {
- rc = PTR_ERR(bp);
- thread->ptrace_bps[i] = NULL;
+ if (rc)
break;
- }
- thread->ptrace_bps[i] = bp;
}
continue;
}
- bp = ptrace_modify_breakpoint(bp, len, type, tsk, 0);
-
- /* Incorrect bp, or we have a bug in bp API */
- if (IS_ERR(bp)) {
- rc = PTR_ERR(bp);
- thread->ptrace_bps[i] = NULL;
+ rc = ptrace_modify_breakpoint(bp, len, type, tsk, 0);
+ if (rc)
break;
- }
- thread->ptrace_bps[i] = bp;
}
/*
* Make a second pass to free the remaining unused breakpoints
@@ -721,9 +712,10 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
{
struct perf_event *bp;
struct thread_struct *t = &tsk->thread;
- DEFINE_BREAKPOINT_ATTR(attr);
+ struct perf_event_attr attr;
if (!t->ptrace_bps[nr]) {
+ hw_breakpoint_init(&attr);
/*
* Put stub len and type to register (reserve) an inactive but
* correct bp
@@ -734,26 +726,32 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
attr.disabled = 1;
bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk);
+
+ /*
+ * CHECKME: the previous code returned -EIO if the addr wasn't
+ * a valid task virtual addr. The new one will return -EINVAL in
+ * this case.
+ * -EINVAL may be what we want for in-kernel breakpoints users,
+ * but -EIO looks better for ptrace, since we refuse a register
+ * writing for the user. And anyway this is the previous
+ * behaviour.
+ */
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ t->ptrace_bps[nr] = bp;
} else {
+ int err;
+
bp = t->ptrace_bps[nr];
- t->ptrace_bps[nr] = NULL;
attr = bp->attr;
attr.bp_addr = addr;
- bp = modify_user_hw_breakpoint(bp, &attr, bp->callback, tsk);
+ err = modify_user_hw_breakpoint(bp, &attr);
+ if (err)
+ return err;
}
- /*
- * CHECKME: the previous code returned -EIO if the addr wasn't a
- * valid task virtual addr. The new one will return -EINVAL in this
- * case.
- * -EINVAL may be what we want for in-kernel breakpoints users, but
- * -EIO looks better for ptrace, since we refuse a register writing
- * for the user. And anyway this is the previous behaviour.
- */
- if (IS_ERR(bp))
- return PTR_ERR(bp);
- t->ptrace_bps[nr] = bp;
return 0;
}
@@ -1460,14 +1458,14 @@ static int genregs32_get(struct task_struct *target,
{
if (kbuf) {
compat_ulong_t *k = kbuf;
- while (count > 0) {
+ while (count >= sizeof(*k)) {
getreg32(target, pos, k++);
count -= sizeof(*k);
pos += sizeof(*k);
}
} else {
compat_ulong_t __user *u = ubuf;
- while (count > 0) {
+ while (count >= sizeof(*u)) {
compat_ulong_t word;
getreg32(target, pos, &word);
if (__put_user(word, u++))
@@ -1488,14 +1486,14 @@ static int genregs32_set(struct task_struct *target,
int ret = 0;
if (kbuf) {
const compat_ulong_t *k = kbuf;
- while (count > 0 && !ret) {
+ while (count >= sizeof(*k) && !ret) {
ret = putreg32(target, pos, *k++);
count -= sizeof(*k);
pos += sizeof(*k);
}
} else {
const compat_ulong_t __user *u = ubuf;
- while (count > 0 && !ret) {
+ while (count >= sizeof(*u) && !ret) {
compat_ulong_t word;
ret = __get_user(word, u++);
if (ret)
@@ -1678,21 +1676,33 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
#endif
}
-void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
- int error_code, int si_code)
+static void fill_sigtrap_info(struct task_struct *tsk,
+ struct pt_regs *regs,
+ int error_code, int si_code,
+ struct siginfo *info)
{
- struct siginfo info;
-
tsk->thread.trap_no = 1;
tsk->thread.error_code = error_code;
- memset(&info, 0, sizeof(info));
- info.si_signo = SIGTRAP;
- info.si_code = si_code;
+ memset(info, 0, sizeof(*info));
+ info->si_signo = SIGTRAP;
+ info->si_code = si_code;
+ info->si_addr = user_mode_vm(regs) ? (void __user *)regs->ip : NULL;
+}
+
+void user_single_step_siginfo(struct task_struct *tsk,
+ struct pt_regs *regs,
+ struct siginfo *info)
+{
+ fill_sigtrap_info(tsk, regs, 0, TRAP_BRKPT, info);
+}
- /* User-mode ip? */
- info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
+void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
+ int error_code, int si_code)
+{
+ struct siginfo info;
+ fill_sigtrap_info(tsk, regs, error_code, si_code, &info);
/* Send us the fake SIGTRAP */
force_sig_info(SIGTRAP, &info, tsk);
}
@@ -1757,29 +1767,22 @@ asmregparm long syscall_trace_enter(struct pt_regs *regs)
asmregparm void syscall_trace_leave(struct pt_regs *regs)
{
+ bool step;
+
if (unlikely(current->audit_context))
audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
trace_sys_exit(regs, regs->ax);
- if (test_thread_flag(TIF_SYSCALL_TRACE))
- tracehook_report_syscall_exit(regs, 0);
-
/*
* If TIF_SYSCALL_EMU is set, we only get here because of
* TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP).
* We already reported this syscall instruction in
- * syscall_trace_enter(), so don't do any more now.
- */
- if (unlikely(test_thread_flag(TIF_SYSCALL_EMU)))
- return;
-
- /*
- * If we are single-stepping, synthesize a trap to follow the
- * system call instruction.
+ * syscall_trace_enter().
*/
- if (test_thread_flag(TIF_SINGLESTEP) &&
- tracehook_consider_fatal_signal(current, SIGTRAP))
- send_sigtrap(current, regs, 0, TRAP_BRKPT);
+ step = unlikely(test_thread_flag(TIF_SINGLESTEP)) &&
+ !test_thread_flag(TIF_SYSCALL_EMU);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, step);
}
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-04-19 16:24:50 +0000