From: Sergey Matyukevich <sergey.matyukevich@xxxxxxxxxxxx> commit b1c6ecfdd06907554518ec384ce8e99889d15193 upstream. Function syscall_trace_exit expects pointer to pt_regs. However r0 is also used to keep syscall return value. Restore pointer to pt_regs before calling syscall_trace_exit. Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Sergey Matyukevich <sergey.matyukevich@xxxxxxxxxxxx> Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arc/kernel/entry.S | 1 + 1 file changed, 1 insertion(+) --- a/arch/arc/kernel/entry.S +++ b/arch/arc/kernel/entry.S @@ -191,6 +191,7 @@ tracesys_exit: st r0, [sp, PT_r0] ; sys call return value in pt_regs ;POST Sys Call Ptrace Hook + mov r0, sp ; pt_regs needed bl @syscall_trace_exit b ret_from_exception ; NOT ret_from_system_call at is saves r0 which ; we'd done before calling post hook above
