Re: [PATCH] signal: don't remove SIGNAL_UNKILLABLE for traced tasks.

From: Oleg Nesterov
Date: Tue Aug 15 2017 - 12:17:04 EST


On 08/15, Jamie Iles wrote:
>
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -1194,7 +1194,11 @@ force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
> recalc_sigpending_and_wake(t);
> }
> }
> - if (action->sa.sa_handler == SIG_DFL)
> + /*
> + * Don't clear SIGNAL_UNKILLABLE for traced tasks, users won't expect
> + * debugging to leave init killable.
> + */
> + if (action->sa.sa_handler == SIG_DFL && !t->ptrace)
> t->signal->flags &= ~SIGNAL_UNKILLABLE;
> ret = specific_send_sig_info(sig, info, t);
> spin_unlock_irqrestore(&t->sighand->siglock, flags);

Acked-by: Oleg Nesterov <oleg@xxxxxxxxxx>