From: Takashi Iwai Date: Mon, 8 Feb 2016 16:36:25 +0000 (+0100) Subject: ALSA: timer: Fix wrong instance passed to slave callbacks X-Git-Tag: firefly_0821_release~3391^2~69 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4333cce1e75701f5ffb0f17cbe43c170e09e7e46;p=firefly-linux-kernel-4.4.55.git ALSA: timer: Fix wrong instance passed to slave callbacks commit 117159f0b9d392fb433a7871426fad50317f06f7 upstream. In snd_timer_notify1(), the wrong timer instance was passed for slave ccallback function. This leads to the access to the wrong data when an incompatible master is handled (e.g. the master is the sequencer timer and the slave is a user timer), as spotted by syzkaller fuzzer. This patch fixes that wrong assignment. BugLink: http://lkml.kernel.org/r/CACT4Y+Y_Bm+7epAb=8Wi=AaWd+DYS7qawX52qxdCfOfY49vozQ@mail.gmail.com Reported-by: Dmitry Vyukov Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- diff --git a/sound/core/timer.c b/sound/core/timer.c index 87be17112573..9e45178231fa 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -422,7 +422,7 @@ static void snd_timer_notify1(struct snd_timer_instance *ti, int event) spin_lock_irqsave(&timer->lock, flags); list_for_each_entry(ts, &ti->slave_active_head, active_list) if (ts->ccallback) - ts->ccallback(ti, event + 100, &tstamp, resolution); + ts->ccallback(ts, event + 100, &tstamp, resolution); spin_unlock_irqrestore(&timer->lock, flags); }