Re: [PATCH 2/2] ptrace: Return the signal to continue with from ptrace_stop

Oleg Nesterov
2022-03-17T18:09:25Z

Not sure I understand this patch, I can't apply it. I guess I need to
clone your tree first, will do later.

Just one question right now,

On 03/15, Eric W. Biederman wrote:
>
> +static int ptrace_stop(int exit_code, int why, int clear_code,
> unsigned long message, kernel_siginfo_t *info)
> __releases(&current->sighand->siglock)
> __acquires(&current->sighand->siglock)
> {
> bool gstop_done = false;
> + bool read_code = true;
>
> if (arch_ptrace_stop_needed()) {
> /*
> @@ -2305,8 +2307,9 @@ static void ptrace_stop(int exit_code, int why, int clear_code,
>
> /* tasklist protects us from ptrace_freeze_traced() */
> __set_current_state(TASK_RUNNING);
> + read_code = false;
> if (clear_code)
> - current->exit_code = 0;
> + exit_code = 0;
> read_unlock(&tasklist_lock);
> }
>
> @@ -2316,8 +2319,10 @@ static void ptrace_stop(int exit_code, int why, int clear_code,
> * any signal-sending on another CPU that wants to examine it.
> */
> spin_lock_irq(&current->sighand->siglock);
> + if (read_code) exit_code = current->exit_code;

style ;)

> current->last_siginfo = NULL;
> current->ptrace_message = 0;
> + current->exit_code = 0;

OK, I like it... but can't we remove the ugly "int clear_code" arg?

Oleg.