diff options
author | Takashi Iwai <tiwai@suse.de> | 2021-11-05 10:15:17 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-17 09:48:19 +0100 |
commit | 9505d4872188205f436c9107781243c29a38666e (patch) | |
tree | 22d19b0d32742becc323b71927f12141892a4cba /sound/core | |
parent | 2c6446168f07bd2baa59288f8aa9e3ae54378027 (diff) |
ALSA: timer: Unconditionally unlink slave instances, too
commit ffdd98277f0a1d15a67a74ae09bee713df4c0dbc upstream.
Like the previous fix (commit c0317c0e8709 "ALSA: timer: Fix
use-after-free problem"), we have to unlink slave timer instances
immediately at snd_timer_stop(), too. Otherwise it may leave a stale
entry in the list if the slave instance is freed before actually
running.
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211105091517.21733-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound/core')
-rw-r--r-- | sound/core/timer.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/sound/core/timer.c b/sound/core/timer.c index 6b7cba0d23e0..d684aa4150aa 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -636,23 +636,22 @@ static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop) static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop) { unsigned long flags; + bool running; spin_lock_irqsave(&slave_active_lock, flags); - if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) { - spin_unlock_irqrestore(&slave_active_lock, flags); - return -EBUSY; - } + running = timeri->flags & SNDRV_TIMER_IFLG_RUNNING; timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING; if (timeri->timer) { spin_lock(&timeri->timer->lock); list_del_init(&timeri->ack_list); list_del_init(&timeri->active_list); - snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP : - SNDRV_TIMER_EVENT_PAUSE); + if (running) + snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP : + SNDRV_TIMER_EVENT_PAUSE); spin_unlock(&timeri->timer->lock); } spin_unlock_irqrestore(&slave_active_lock, flags); - return 0; + return running ? 0 : -EBUSY; } /* |