Re: [PATCH] kill an obsolete sub-thread-ptrace stuff

[Oleg Nesterov]

On 08/03, Roland McGrath wrote:
>
> > There is a couple of subtle checks which were needed to handle ptracing from
> > the same thread group. This was deprecated a long ago, imho this code just
> > complicates the understanding.
> 
> Looks ok to me.

Thanks!

> > And, the "->parent->signal->flags & SIGNAL_GROUP_EXIT" check in exit_notify()
> > is not right. SIGNAL_GROUP_EXIT can mean exec(), not exit_group(). This means
> > ptracer can lose a ptraced zombie on exec(). Minor problem, but still the bug.
> 
> This bug never happens because this check is only in the now-impossible
> ptrace-same-group case.

This means that changelog is wrong and should be changed.

However, I disagree. exit_notify() doesn't check the ptrace-same-group case. So,
unless I missed something, we set EXIT_DEAD in any case, even if ptracer doesn't
belong to our thread group.

No?

Oleg.

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