ALSA: seq: oss: Skip events until fully initialized

When an OSS sequencer device is opened, it creates a sequencer port,
then further initializes the internal states like a timer instance,
etc.  Since the sequencer port is published, an event can be already
delivered, and this may hit unexpected event handling, which can
eventually cause a NULL dereference (like the timer start/stop event
triggered before the timer initialization).

For avoiding such a race, introduce a simple guard and skips the event
processing until the port is fully initialized.
At releasing the device, in turn, clear this guard, so that any input
events will be discarded during the teardown.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20261016161930.482309-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

0 files changed, 0 insertions, 0 deletions