This is a note to let you know that I've just added the patch titled ALSA: dummy: Disable switching timer backend via sysfs to the 4.4-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-dummy-disable-switching-timer-backend-via-sysfs.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 7ee96216c31aabe1eb42fb91ff50dae9fcd014b2 Mon Sep 17 00:00:00 2001 From: Takashi Iwai <tiwai@xxxxxxx> Date: Thu, 28 Jan 2016 07:54:16 +0100 Subject: ALSA: dummy: Disable switching timer backend via sysfs From: Takashi Iwai <tiwai@xxxxxxx> commit 7ee96216c31aabe1eb42fb91ff50dae9fcd014b2 upstream. ALSA dummy driver can switch the timer backend between system timer and hrtimer via its hrtimer module option. This can be also switched dynamically via sysfs, but it may lead to a memory corruption when switching is done while a PCM stream is running; the stream instance for the newly switched timer method tries to access the memory that was allocated by another timer method although the sizes differ. As the simplest fix, this patch just disables the switch via sysfs by dropping the writable bit. BugLink: http://lkml.kernel.org/r/CACT4Y+ZGEeEBntHW5WHn2GoeE0G_kRrCmUh6=dWyy-wfzvuJLg@xxxxxxxxxxxxxx Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/drivers/dummy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/sound/drivers/dummy.c +++ b/sound/drivers/dummy.c @@ -87,7 +87,7 @@ MODULE_PARM_DESC(pcm_substreams, "PCM su module_param(fake_buffer, bool, 0444); MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations."); #ifdef CONFIG_HIGH_RES_TIMERS -module_param(hrtimer, bool, 0644); +module_param(hrtimer, bool, 0444); MODULE_PARM_DESC(hrtimer, "Use hrtimer as the timer source."); #endif Patches currently in stable-queue which might be from tiwai@xxxxxxx are queue-4.4/alsa-seq-fix-race-at-closing-in-virmidi-driver.patch queue-4.4/alsa-hda-fix-bad-dereference-of-jack-object.patch queue-4.4/alsa-usb-audio-add-quirk-for-microsoft-lifecam-hd-6000.patch queue-4.4/alsa-rawmidi-remove-kernel-warning-for-null-user-space-buffer-check.patch queue-4.4/alsa-usb-audio-fix-oppo-ha-1-vendor-id.patch queue-4.4/alsa-timer-fix-race-at-concurrent-reads.patch queue-4.4/alsa-hda-realtek-support-dell-headset-mode-for-alc225.patch queue-4.4/alsa-hda-fix-static-checker-warning-in-patch_hdmi.c.patch queue-4.4/alsa-seq-fix-lockdep-warnings-due-to-double-mutex-locks.patch queue-4.4/alsa-usb-audio-fix-teac-ud-501-ud-503-nt-503-usb-delay.patch queue-4.4/alsa-timer-fix-wrong-instance-passed-to-slave-callbacks.patch queue-4.4/alsa-hda-disable-dynamic-clock-gating-on-broxton-before-reset.patch queue-4.4/alsa-hda-realtek-support-headset-mode-for-alc225.patch queue-4.4/alsa-hda-implement-loopback-control-switch-for-realtek-and-other-codecs.patch queue-4.4/alsa-hda-realtek-new-codec-support-of-alc225.patch queue-4.4/alsa-seq-degrade-the-error-message-for-too-many-opens.patch queue-4.4/alsa-compress-disable-get_codec_caps-ioctl-for-some-architectures.patch queue-4.4/alsa-rawmidi-make-snd_rawmidi_transmit-race-free.patch queue-4.4/alsa-hda-fix-speaker-output-from-vaio-aio-machines.patch queue-4.4/alsa-bebob-use-a-signed-return-type-for-get_formation_index.patch queue-4.4/alsa-add-missing-dependency-on-config_snd_timer.patch queue-4.4/alsa-dummy-implement-timer-backend-switching-more-safely.patch queue-4.4/alsa-dummy-disable-switching-timer-backend-via-sysfs.patch queue-4.4/alsa-seq-fix-incorrect-sanity-check-at-snd_seq_oss_synth_cleanup.patch queue-4.4/alsa-seq-fix-yet-another-races-among-alsa-timer-accesses.patch queue-4.4/alsa-usb-audio-avoid-freeing-umidi-object-twice.patch queue-4.4/revert-alsa-hda-fix-noise-on-gigabyte-z170x-mobo.patch queue-4.4/alsa-hda-add-fixup-for-mac-mini-7-1-model.patch queue-4.4/alsa-usb-audio-add-native-dsd-support-for-ps-audio-nuwave-dac.patch queue-4.4/alsa-timer-fix-leftover-link-at-closing.patch queue-4.4/alsa-rawmidi-fix-race-at-copying-updating-the-position.patch queue-4.4/alsa-pcm-fix-potential-deadlock-in-oss-emulation.patch queue-4.4/alsa-timer-fix-link-corruption-due-to-double-start-or-stop.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