This is a note to let you know that I've just added the patch titled ALSA: seq: Fix race at timer setup and close to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: alsa-seq-fix-race-at-timer-setup-and-close.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 3567eb6af614dac436c4b16a8d426f9faed639b3 Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai@xxxxxxx> Date: Tue, 12 Jan 2016 15:36:27 +0100 Subject: ALSA: seq: Fix race at timer setup and close From: Takashi Iwai <tiwai@xxxxxxx> commit 3567eb6af614dac436c4b16a8d426f9faed639b3 upstream. ALSA sequencer code has an open race between the timer setup ioctl and the close of the client. This was triggered by syzkaller fuzzer, and a use-after-free was caught there as a result. This patch papers over it by adding a proper queue->timer_mutex lock around the timer-related calls in the relevant code path. Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Tested-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/core/seq/seq_queue.c | 2 ++ 1 file changed, 2 insertions(+) --- a/sound/core/seq/seq_queue.c +++ b/sound/core/seq/seq_queue.c @@ -142,8 +142,10 @@ static struct snd_seq_queue *queue_new(i static void queue_delete(struct snd_seq_queue *q) { /* stop and release the timer */ + mutex_lock(&q->timer_mutex); snd_seq_timer_stop(q->timer); snd_seq_timer_close(q); + mutex_unlock(&q->timer_mutex); /* wait until access free */ snd_use_lock_sync(&q->use_lock); /* release resources... */ Patches currently in stable-queue which might be from tiwai@xxxxxxx are queue-4.1/alsa-hrtimer-fix-stall-by-hrtimer_cancel.patch queue-4.1/alsa-hda-fix-white-noise-on-dell-latitude-e5550.patch queue-4.1/alsa-hda-fix-the-headset-mic-detection-problem-for-a-dell-laptop.patch queue-4.1/alsa-timer-harden-slave-timer-list-handling.patch queue-4.1/alsa-timer-fix-double-unlink-of-active_list.patch queue-4.1/alsa-hda-add-fixup-for-acer-aspire-one-cloudbook-14.patch queue-4.1/alsa-control-avoid-kernel-warnings-from-tlv-ioctl-with-numid-0.patch queue-4.1/alsa-hda-flush-the-pending-probe-work-at-remove.patch queue-4.1/alsa-usb-audio-add-sample-rate-inquiry-quirk-for-audioquest-dragonfly.patch queue-4.1/alsa-hda-apply-hp-headphone-fixups-more-generically.patch queue-4.1/alsa-hda-set-codec-to-d3-at-reboot-shutdown-on-thinkpads.patch queue-4.1/alsa-hda-realtek-fix-silent-headphone-output-on-macpro-4-1-v2.patch queue-4.1/alsa-rme96-fix-unexpected-volume-reset-after-rate-changes.patch queue-4.1/alsa-fireworks-bebob-oxfw-dice-enable-to-make-as-built-in.patch queue-4.1/alsa-hda-set-skl-hda-controller-power-at-freeze-and-thaw.patch queue-4.1/alsa-hda-add-inverted-dmic-for-packard-bell-dots.patch queue-4.1/alsa-usb-add-native-dsd-support-for-oppo-ha-1.patch queue-4.1/alsa-hda-add-intel-lewisburg-device-ids-audio.patch queue-4.1/alsa-hda-add-a-fixup-for-thinkpad-x1-carbon-2nd.patch queue-4.1/alsa-seq-fix-race-at-timer-setup-and-close.patch queue-4.1/alsa-pcm-fix-snd_pcm_hw_params-struct-copy-in-compat-mode.patch queue-4.1/alsa-seq-fix-snd_seq_call_port_info_ioctl-in-compat-mode.patch queue-4.1/alsa-hda-disable-64bit-address-for-creative-hda-controllers.patch queue-4.1/alsa-seq-fix-missing-null-check-at-remove_events-ioctl.patch queue-4.1/alsa-usb-audio-fix-mixer-ctl-regression-of-native-instrument-devices.patch queue-4.1/alsa-usb-audio-add-a-more-accurate-volume-quirk-for-audioquest-dragonfly.patch queue-4.1/alsa-hda-fix-noise-problems-on-thinkpad-t440s.patch queue-4.1/alsa-timer-handle-disconnection-more-safely.patch queue-4.1/alsa-hda-fix-bass-pin-fixup-for-asus-n550jx.patch queue-4.1/alsa-timer-fix-race-among-timer-ioctls.patch queue-4.1/alsa-hda-apply-pin-fixup-for-hp-probook-6550b.patch queue-4.1/alsa-hda-apply-click-noise-workaround-for-thinkpads-generically.patch queue-4.1/alsa-hda-fix-noise-on-gigabyte-z170x-mobo.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html