2 files changed, 15 insertions, 10 deletions

diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index ee81dbc6fa10..d863bbf0f1f5 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -455,7 +455,6 @@ __sys_trace:
 
 __sys_trace_return:
         str     r0, [sp, #S_R0 + S_OFF]!        @ save returned r0
-        mov     r1, scno
         mov     r0, sp
         bl      syscall_trace_exit
         b       ret_slow_syscall
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 518536d93fba..03deeffd9f6d 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -957,17 +957,23 @@ asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
         return scno;
 }
 
-asmlinkage int syscall_trace_exit(struct pt_regs *regs, int scno)
+asmlinkage void syscall_trace_exit(struct pt_regs *regs)
 {
-        current_thread_info()->syscall = scno;
-
-        if (test_thread_flag(TIF_SYSCALL_TRACE))
-                scno = tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
+        /*
+         * 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, scno);
-
-        audit_syscall_exit(regs);
+                trace_sys_exit(regs, regs_return_value(regs));
 
-        return scno;
+        if (test_thread_flag(TIF_SYSCALL_TRACE))
+                tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
 }