usb: gadget: u_audio: fix race condition on endpoint stop

[ Upstream commit 068fdad20454f815e61e6f6eb9f051a8b3120e88 ]

If the endpoint completion callback is call right after the ep_enabled flag
is cleared and before usb_ep_dequeue() is call, we could do a double free
on the request and the associated buffer.

Fix this by clearing ep_enabled after all the endpoint requests have been
dequeued.

Change-Id: I3c9a0d635bb26fb73e628710e178f4a2278bfde4
Fixes: 7de8681be2cd ("usb: gadget: u_audio: Free requests only after callback")
Cc: stable <stable@vger.kernel.org>
Reported-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20210827092927.366482-1-jbrunet@baylibre.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Git-commit: 6a600523
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git


Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>