From 25ba820ef36bdbaf9884adeac69b6e1821a7df76 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 8 Aug 2022 16:07:21 +0100 Subject: [PATCH] nios2: traced syscall does need to check the syscall number all checks done before letting the tracer modify the register state are worthless... Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro Signed-off-by: Dinh Nguyen --- arch/nios2/kernel/entry.S | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/nios2/kernel/entry.S b/arch/nios2/kernel/entry.S index 8f41ef5..fd24490 100644 --- a/arch/nios2/kernel/entry.S +++ b/arch/nios2/kernel/entry.S @@ -255,9 +255,9 @@ traced_system_call: ldw r6, PT_R6(sp) ldw r7, PT_R7(sp) - /* Fetch the syscall function, we don't need to check the boundaries - * since this is already done. - */ + /* Fetch the syscall function. */ + movui r1, __NR_syscalls + bgeu r2, r1, traced_invsyscall slli r1, r2, 2 movhi r11,%hiadj(sys_call_table) add r1, r1, r11 @@ -287,6 +287,11 @@ end_translate_rc_and_ret2: RESTORE_SWITCH_STACK br ret_from_exception + /* If the syscall number was invalid return ENOSYS */ +traced_invsyscall: + movi r2, -ENOSYS + br translate_rc_and_ret2 + Luser_return: GET_THREAD_INFO r11 /* get thread_info pointer */ ldw r10, TI_FLAGS(r11) /* get thread_info->flags */ -- 2.7.4