Takashi Iwai 3fa6993fef ALSA: timer: Fix negative queue usage by racy accesses
The user timer tu->qused counter may go to a negative value when
multiple concurrent reads are performed since both the check and the
decrement of tu->qused are done in two individual locked contexts.
This results in bogus read outs, and the endless loop in the
user-space side.

The fix is to move the decrement of the tu->qused counter into the
same spinlock context as the zero-check of the counter.

Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-07-04 14:02:15 +02:00
..
2016-01-20 09:59:27 +01:00
2015-08-31 16:25:22 +02:00