Takashi Iwai 586d71ddee ALSA: hda: realtek: Fix race at concurrent COEF updates
commit b837a9f5ab3bdfab9233c9f98a6bef717673a3e5 upstream.

The COEF access is done with two steps: setting the index then read or
write the data.  When multiple COEF accesses are performed
concurrently, the index and data might be paired unexpectedly.
In most cases, this isn't a big problem as the COEF setup is done at
the initialization, but some dynamic changes like the mute LED may hit
such a race.

For avoiding the racy COEF accesses, this patch introduces a new
mutex coef_mutex to alc_spec, and wrap the COEF accessing functions
with it.

Reported-by: Alexander Sergeyev <sergeev917@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220111195229.a77wrpjclqwrx4bx@localhost.localdomain
Link: https://lore.kernel.org/r/20220131075738.24323-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-08 18:34:03 +01:00
..
2021-09-03 15:33:47 -07:00
2021-04-27 08:39:39 +02:00
2021-08-04 08:07:58 +02:00
2021-03-07 09:07:16 +01:00
2021-03-07 09:07:16 +01:00