RE: [PATCH] ptrace RSE bug

Petr Tesarik
2007-11-12T16:11:27Z

On Mon, 2007-11-12 at 16:41 +0100, Petr Tesarik wrote:
> On Sun, 2007-11-11 at 18:14 -0800, Roland McGrath wrote:
>[...]
> Hi Roland,
>
> the trouble is I used the current ia64 patch and even inserted an
> msleep(10) into ptrace_stop() to make sure it does sleep but I don't see
> any problems. I added the following code between arch_ptrace_stop(1) and
> set_current_state(TASK_TRACED):
>
> msleep(10);
> if (unlikely(sigismember(&current->pending.signal, SIGKILL)))
> printk(KERN_INFO "%d (%s): Got SIGKILL in ptrace_stop\n",
> current->pid, current->comm);
>
> I ran strace on a simple program (calling gettimeofday() in an endless
> loop) and killed it with SIGKILL. The program exited correctly and I got
> the message in syslog. I'm puzzled. :/ Is this not the correct place
> where the race condition should happen?

Ah, Roland, you're right, strace ends with:

+++ killed by SIGKILL +++
Process 2946 detached

I've just realized that it's exactly what SHOULDN'T happen. Sorry for
the fuss.

Regards,
Petr Tesarik