From: Takashi Iwai Date: Thu, 4 Feb 2016 16:06:13 +0000 (+0100) Subject: ALSA: timer: Fix leftover link at closing X-Git-Tag: v3.2.78~24 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=98ea665bd5fd68a194c1263b2d7619f9dd22526a;p=pandora-kernel.git ALSA: timer: Fix leftover link at closing commit 094fd3be87b0f102589e2d5c3fa5d06b7e20496d upstream. In ALSA timer core, the active timer instance is managed in active_list linked list. Each element is added / removed dynamically at timer start, stop and in timer interrupt. The problem is that snd_timer_interrupt() has a thinko and leaves the element in active_list when it's the last opened element. This eventually leads to list corruption or use-after-free error. This hasn't been revealed because we used to delete the list forcibly in snd_timer_stop() in the past. However, the recent fix avoids the double-stop behavior (in commit [f784beb75ce8: ALSA: timer: Fix link corruption due to double start or stop]), and this leak hits reality. This patch fixes the link management in snd_timer_interrupt(). Now it simply unlinks no matter which stream is. BugLink: http://lkml.kernel.org/r/CACT4Y+Yy2aukHP-EDp8-ziNqNNmb-NTf=jDWXMP7jB8HDa2vng@mail.gmail.com Reported-by: Dmitry Vyukov Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings --- Reading git-diff-tree failed