signals: dequeue_signal: don't check SIGNAL_GROUP_EXIT when setting SIGNAL_STOP_DEQUEUED
authorOleg Nesterov <oleg@tv-sign.ru>
Fri, 25 Jul 2008 08:47:30 +0000 (01:47 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 25 Jul 2008 17:53:38 +0000 (10:53 -0700)
commit92413d771e7123304fb4b9efd2a00cccc946e383
treec973360a9bec6c965b9f4b41923357feec14aa3a
parent3854a771821c970065e3203a0b40ddc4101538cc
signals: dequeue_signal: don't check SIGNAL_GROUP_EXIT when setting SIGNAL_STOP_DEQUEUED

dequeue_signal() checks SIGNAL_GROUP_EXIT before setting
SIGNAL_STOP_DEQUEUED.  This was added by
788e05a67c343fa22f2ae1d3ca264e7f15c25eaf a long ago to avoid the
coredump/SIGSTOP race.

Since then the related code was changed, and now this subtle check is both
incomplete and unneeded at the same time.  It is incomplete because
nowadays exec() doesn't set SIGNAL_GROUP_EXIT, so in fact we should check
signal_group_exit() to avoid a similar race.  Fortunately, we doesn't need
the check at all.  The only function which relies on SIGNAL_STOP_DEQUEUED
is do_signal_stop(), and it ignores this flag if signal_group_exit() == T,
this covers the SIGNAL_GROUP_EXIT case.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/signal.c