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Diffstat (limited to 'arch')
-rw-r--r--arch/arm64/include/asm/thread_info.h1
-rw-r--r--arch/arm64/kernel/ptrace.c25
-rw-r--r--arch/arm64/kernel/signal.c11
-rw-r--r--arch/arm64/kernel/syscall.c2
4 files changed, 23 insertions, 16 deletions
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
index 6ea8b6a26ae9..5e784e16ee89 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -93,6 +93,7 @@ void arch_release_task_struct(struct task_struct *tsk);
#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
#define _TIF_UPROBE (1 << TIF_UPROBE)
#define _TIF_FSCHECK (1 << TIF_FSCHECK)
+#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
#define _TIF_32BIT (1 << TIF_32BIT)
#define _TIF_SVE (1 << TIF_SVE)
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 68b7f34a08f5..057d4aa1af4d 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -1818,12 +1818,23 @@ static void tracehook_report_syscall(struct pt_regs *regs,
saved_reg = regs->regs[regno];
regs->regs[regno] = dir;
- if (dir == PTRACE_SYSCALL_EXIT)
+ if (dir == PTRACE_SYSCALL_ENTER) {
+ if (tracehook_report_syscall_entry(regs))
+ forget_syscall(regs);
+ regs->regs[regno] = saved_reg;
+ } else if (!test_thread_flag(TIF_SINGLESTEP)) {
tracehook_report_syscall_exit(regs, 0);
- else if (tracehook_report_syscall_entry(regs))
- forget_syscall(regs);
+ regs->regs[regno] = saved_reg;
+ } else {
+ regs->regs[regno] = saved_reg;
- regs->regs[regno] = saved_reg;
+ /*
+ * Signal a pseudo-step exception since we are stepping but
+ * tracer modifications to the registers may have rewound the
+ * state machine.
+ */
+ tracehook_report_syscall_exit(regs, 1);
+ }
}
int syscall_trace_enter(struct pt_regs *regs)
@@ -1851,12 +1862,14 @@ int syscall_trace_enter(struct pt_regs *regs)
void syscall_trace_exit(struct pt_regs *regs)
{
+ unsigned long flags = READ_ONCE(current_thread_info()->flags);
+
audit_syscall_exit(regs);
- if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ if (flags & _TIF_SYSCALL_TRACEPOINT)
trace_sys_exit(regs, regs_return_value(regs));
- if (test_thread_flag(TIF_SYSCALL_TRACE))
+ if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP))
tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
rseq_syscall(regs);
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 801d56cdf701..3b4f31f35e45 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -800,7 +800,6 @@ static void setup_restart_syscall(struct pt_regs *regs)
*/
static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
{
- struct task_struct *tsk = current;
sigset_t *oldset = sigmask_to_save();
int usig = ksig->sig;
int ret;
@@ -824,14 +823,8 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
*/
ret |= !valid_user_regs(&regs->user_regs, current);
- /*
- * Fast forward the stepping logic so we step into the signal
- * handler.
- */
- if (!ret)
- user_fastforward_single_step(tsk);
-
- signal_setup_done(ret, ksig, 0);
+ /* Step into the signal handler if we are stepping */
+ signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
}
/*
diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c
index 5f5b868292f5..7c14466a12af 100644
--- a/arch/arm64/kernel/syscall.c
+++ b/arch/arm64/kernel/syscall.c
@@ -139,7 +139,7 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr,
if (!has_syscall_work(flags) && !IS_ENABLED(CONFIG_DEBUG_RSEQ)) {
local_daif_mask();
flags = current_thread_info()->flags;
- if (!has_syscall_work(flags)) {
+ if (!has_syscall_work(flags) && !(flags & _TIF_SINGLESTEP)) {
/*
* We're off to userspace, where interrupts are
* always enabled after we restore the flags from