linux-kernel - [PATCH] rtmutex: Fix incorrect usage of rt_mutex_waiter_is_top

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:   Wed, 15 Dec 2021 15:01:51 +0800
From:   Zqiang <qiang1.zhang@...el.com>
To:     peterz@...radead.org, tglx@...utronix.de
Cc:     linux-kernel@...r.kernel.org
Subject: [PATCH] rtmutex: Fix incorrect usage of rt_mutex_waiter_is_top_waiter()

The condition for exiting spin is that the rt_mutex_waiter_is_top_waiter()
return false rather than return true.

Fixes: c3123c431447 ("locking/rtmutex: Dont dereference waiter lockless")
Signed-off-by: Zqiang <qiang1.zhang@...el.com>
---
 kernel/locking/rtmutex.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 0c1f2e3f019a..8555c4efe97c 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -1383,7 +1383,7 @@ static bool rtmutex_spin_on_owner(struct rt_mutex_base *lock,
 		 *  - the VCPU on which owner runs is preempted
 		 */
 		if (!owner_on_cpu(owner) || need_resched() ||
-		    rt_mutex_waiter_is_top_waiter(lock, waiter)) {
+		    !rt_mutex_waiter_is_top_waiter(lock, waiter)) {
 			res = false;
 			break;
 		}
-- 
2.25.1