UPSTREAM: ALSA: seq: Don't allow resizing pool in use
This is a fix for a (sort of) fallout in the recent commit
d15d662e89fc ("ALSA: seq: Fix racy pool initializations") for
CVE-2018-1000004.
As the pool resize deletes the existing cells, it may lead to a race
when another thread is writing concurrently, eventually resulting a
UAF.
A simple workaround is not to allow the pool resizing when the pool is
in use. It's an invalid behavior in anyway.
BUG=834716
TEST=None
Change-Id: Ic2b9cb355273a12cd8657fe2d57ce8641edcbc1c
Fixes: d15d662e89fc ("ALSA: seq: Fix racy pool initializations")
Reported-by: <long7573@126.com>
Reported-by: Nicolai Stange <nstange@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
(cherry picked from commit d85739367c6d56e475c281945c68fdb05ca74b4c)
Signed-off-by: Zubin Mithra <zsm@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1019392
Reviewed-by: Guenter Roeck <groeck@chromium.org>
1 file changed
