diff options
author | Takashi Iwai <tiwai@suse.de> | 2021-11-05 10:15:17 +0100 |
---|---|---|
committer | Takashi Iwai <tiwai@suse.de> | 2021-11-05 11:27:27 +0100 |
commit | ffdd98277f0a1d15a67a74ae09bee713df4c0dbc (patch) | |
tree | c6e58a9e896d4d96c45eaf983797a124bebb2c2b | |
parent | dce9446192439eaac81c21f517325fb473735e53 (diff) |
ALSA: timer: Unconditionally unlink slave instances, too
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>
-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 4f9bab931951..b3214baa8919 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -665,23 +665,22 @@ 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; } /* |