Commit 59c7ecf1 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar
Browse files

futex: Correct the number of requeued waiters for PI 



The accounting is wrong when either the PI sanity check or the
requeue PI operation fails. Adjust it in the failure path.

Will be simplified in the next step.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211305.416427548@linutronix.de
parent 8e74633d

kernel/futex.c

+4 −0
Original line number Diff line number Diff line
@@ -2116,6 +2116,8 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags, 


		/* Ensure we requeue to the expected futex for requeue_pi. */

		if (requeue_pi && !match_futex(this->requeue_pi_key, &key2)) {

			/* Don't account for it */

			task_count--;

			ret = -EINVAL;

			break;

		}
@@ -2157,6 +2159,8 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags, 
				 */

				this->pi_state = NULL;

				put_pi_state(pi_state);

				/* Don't account for it */

				task_count--;

				/*

				 * We stop queueing more waiters and let user

				 * space deal with the mess.