The loops for read and write in PCM OSS emulation have no proper check
of pending signals, and they keep processing even after user tries to
break. This results in a very long delay, often seen as RCU stall
when a huge unprocessed bytes remain queued. The bug could be easily
triggered by syzkaller.
As a simple workaround, this patch adds the proper check of pending
signals and aborts the loop appropriately.
Reported-by: syzbot+993cb4cfcbbff3947c21@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
29159a4ed7