mirrors
/
anolis-cloud-kernel
mirror of https://gitee.com/anolis/cloud-kernel.git
8
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

rtmutex: Drop rt_mutex::wait_lock before scheduling 

ANBZ: #12608

commit d33d26036a upstream.

rt_mutex_handle_deadlock() is called with rt_mutex::wait_lock held.  In the
good case it returns with the lock held and in the deadlock case it emits a
warning and goes into an endless scheduling loop with the lock held, which
triggers the 'scheduling in atomic' warning.

Unlock rt_mutex::wait_lock in the dead lock case before issuing the warning
and dropping into the schedule for ever loop.

[ tglx: Moved unlock before the WARN(), removed the pointless comment,
  	massaged changelog, added Fixes tag ]

Fixes: 3d5c9340d1 ("rtmutex: Handle deadlock detection smarter")
Signed-off-by: Roland Xu <mu001999@outlook.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/ME0P300MB063599BEF0743B8FA339C2CECC802@ME0P300MB0635.AUSP300.PROD.OUTLOOK.COM

[Fixes conflicts]
Fixes: CVE-2024-46829
Signed-off-by: Xiao Long <xiaolong@openanolis.org>
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Reviewed-by: Cruz Zhao <CruzZhao@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/4365
This commit is contained in:
Roland Xu 2024-08-15 10:58:13 +08:00 committed by 小龙
parent 4acd790580
commit 910c0214dc
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
kernel/locking/rtmutex.c
View File

@ -1184,6 +1184,7 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
}
static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
struct rt_mutex *lock,
struct rt_mutex_waiter *w)
{
/*
@ -1193,10 +1194,10 @@ static void rt_mutex_handle_deadlock(int res, int detect_deadlock,
if (res != -EDEADLOCK || detect_deadlock)
return;
/*
* Yell lowdly and stop the task right here.
*/
raw_spin_unlock_irq(&lock->wait_lock);
rt_mutex_print_deadlock(w);
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
schedule();
@ -1248,7 +1249,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
if (unlikely(ret)) {
__set_current_state(TASK_RUNNING);
remove_waiter(lock, &waiter);
rt_mutex_handle_deadlock(ret, chwalk, &waiter);
rt_mutex_handle_deadlock(ret, chwalk, lock, &waiter);
}
/*