summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorOleg Nesterov <oleg@tv-sign.ru>2008-07-25 01:47:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-25 10:53:38 -0700
commit96347e7759e2e433c427defa0fa1adfc8cce6226 (patch)
tree0b78316c887be06b269288d7306d6cac038fe644
parent4b7a1304267bff68260ae861784b27130e805be3 (diff)
downloadop-kernel-dev-96347e7759e2e433c427defa0fa1adfc8cce6226.zip
op-kernel-dev-96347e7759e2e433c427defa0fa1adfc8cce6226.tar.gz
posix timers: release_posix_timer: kill the bogus put_task_struct(->it_process);
release_posix_timer() can't be called with ->it_process != NULL. Once sys_timer_create() sets ->it_process it must not call release_posix_timer(), otherwise we can race with another thread doing sys_timer_delete(), this timer is visible to idr_find() and unlocked. The same is true for two other callers (actually, for any possible caller), sys_timer_delete() and itimer_delete(). They must clear ->it_process before unlock_timer() + release_posix_timer(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Roland McGrath <roland@redhat.com> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--kernel/posix-timers.c3
1 files changed, 0 insertions, 3 deletions
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 17f5326..9a21681 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -449,9 +449,6 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
spin_unlock_irqrestore(&idr_lock, flags);
}
sigqueue_free(tmr->sigq);
- if (unlikely(tmr->it_process) &&
- tmr->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID))
- put_task_struct(tmr->it_process);
kmem_cache_free(posix_timers_cache, tmr);
}
OpenPOWER on IntegriCloud