[PATCH 5.10 319/518] signal: Replace BUG_ON()s

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

5.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

[ Upstream commit 7f8af7bac5380f2d95a63a6f19964e22437166e1 ]

These really can be handled gracefully without killing the machine.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
Reviewed-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 kernel/signal.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/kernel/signal.c b/kernel/signal.c
index bfc1da526ebbe..7a9af6d4f2b01 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1817,10 +1817,11 @@ struct sigqueue *sigqueue_alloc(void)
 
 void sigqueue_free(struct sigqueue *q)
 {
-	unsigned long flags;
 	spinlock_t *lock = &current->sighand->siglock;
+	unsigned long flags;
 
-	BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
+	if (WARN_ON_ONCE(!(q->flags & SIGQUEUE_PREALLOC)))
+		return;
 	/*
 	 * We must hold ->siglock while testing q->list
 	 * to serialize with collect_signal() or with
@@ -1848,7 +1849,10 @@ int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type)
 	unsigned long flags;
 	int ret, result;
 
-	BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
+	if (WARN_ON_ONCE(!(q->flags & SIGQUEUE_PREALLOC)))
+		return 0;
+	if (WARN_ON_ONCE(q->info.si_code != SI_TIMER))
+		return 0;
 
 	ret = -1;
 	rcu_read_lock();
@@ -1867,7 +1871,6 @@ int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type)
 		 * If an SI_TIMER entry is already queue just increment
 		 * the overrun count.
 		 */
-		BUG_ON(q->info.si_code != SI_TIMER);
 		q->info.si_overrun++;
 		result = TRACE_SIGNAL_ALREADY_PENDING;
 		goto out;
-- 
2.43.0