signals: SI_USER: Masquerade si_pid when crossing pid ns boundary

When sending a signal to a descendant namespace, set ->si_pid to 0 since
the sender does not have a pid in the receiver's namespace.

Note:
	- If rt_sigqueueinfo() sets si_code to SI_USER when sending a
	  signal across a pid namespace boundary, the value in ->si_pid
	  will be cleared to 0.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sukadev Bhattiprolu 2009-04-02 16:58:09 -07:00 committed by Linus Torvalds
parent b3bfa0cba8
commit 6588c1e3ff

View File

@ -883,6 +883,8 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
break;
default:
copy_siginfo(&q->info, info);
if (from_ancestor_ns)
q->info.si_pid = 0;
break;
}
} else if (!is_si_special(info)) {