From: Al Viro viro@zeniv.linux.org.uk
stable inclusion from stable-v5.10.138 commit 8d0118a027e3c9ab39e31b1fafdb7103922ef3c3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60QFD
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit 25ba820ef36bdbaf9884adeac69b6e1821a7df76 upstream.
all checks done before letting the tracer modify the register state are worthless...
Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Dinh Nguyen dinguyen@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Reviewed-by: Wei Li liwei391@huawei.com --- 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 8f41ef5b0399..fd2449031d08 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 */