path: root/sound
diff options
authorTakashi Iwai <tiwai@suse.de>2017-02-06 15:09:48 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-02-14 15:25:41 -0800
commit23b1595b977c9ce4fe498363c636a555c216a9e2 (patch)
tree3b2ec312a9992cc0a2aad6e5bc283f71a6e94503 /sound
parent5024b2fb8e49091044e450a0548979bb711588d6 (diff)
ALSA: seq: Don't handle loop timeout at snd_seq_pool_done()
commit 37a7ea4a9b81f6a864c10a7cb0b96458df5310a3 upstream. snd_seq_pool_done() syncs with closing of all opened threads, but it aborts the wait loop with a timeout, and proceeds to the release resource even if not all threads have been closed. The timeout was 5 seconds, and if you run a crazy stuff, it can exceed easily, and may result in the access of the invalid memory address -- this is what syzkaller detected in a bug report. As a fix, let the code graduate from naiveness, simply remove the loop timeout. BugLink: http://lkml.kernel.org/r/CACT4Y+YdhDV2H5LLzDTJDVF-qiYHUHhtRaW4rbb4gUhTCQB81w@mail.gmail.com Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound')
1 files changed, 1 insertions, 8 deletions
diff --git a/sound/core/seq/seq_memory.c b/sound/core/seq/seq_memory.c
index c850345c43b5..dfa5156f3585 100644
--- a/sound/core/seq/seq_memory.c
+++ b/sound/core/seq/seq_memory.c
@@ -419,7 +419,6 @@ int snd_seq_pool_done(struct snd_seq_pool *pool)
unsigned long flags;
struct snd_seq_event_cell *ptr;
- int max_count = 5 * HZ;
if (snd_BUG_ON(!pool))
return -EINVAL;
@@ -432,14 +431,8 @@ int snd_seq_pool_done(struct snd_seq_pool *pool)
if (waitqueue_active(&pool->output_sleep))
- while (atomic_read(&pool->counter) > 0) {
- if (max_count == 0) {
- pr_warn("ALSA: snd_seq_pool_done timeout: %d cells remain\n", atomic_read(&pool->counter));
- break;
- }
+ while (atomic_read(&pool->counter) > 0)
- max_count--;
- }
/* release all resources */
spin_lock_irqsave(&pool->lock, flags);