From: Greg Kroah-Hartman Date: Sat, 23 Apr 2022 11:01:12 +0000 (+0200) Subject: 4.9-stable patches X-Git-Tag: v4.9.312~62 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e5041cc7dcb8578901f2c5d41da2e40e2ada6042;p=thirdparty%2Fkernel%2Fstable-queue.git 4.9-stable patches added patches: alsa-usb-audio-clear-midi-port-active-flag-after-draining.patch --- diff --git a/queue-4.9/alsa-usb-audio-clear-midi-port-active-flag-after-draining.patch b/queue-4.9/alsa-usb-audio-clear-midi-port-active-flag-after-draining.patch new file mode 100644 index 00000000000..9fe5ece3c26 --- /dev/null +++ b/queue-4.9/alsa-usb-audio-clear-midi-port-active-flag-after-draining.patch @@ -0,0 +1,41 @@ +From 0665886ad1392e6b5bae85d7a6ccbed48dca1522 Mon Sep 17 00:00:00 2001 +From: Takashi Iwai +Date: Wed, 20 Apr 2022 15:02:47 +0200 +Subject: ALSA: usb-audio: Clear MIDI port active flag after draining + +From: Takashi Iwai + +commit 0665886ad1392e6b5bae85d7a6ccbed48dca1522 upstream. + +When a rawmidi output stream is closed, it calls the drain at first, +then does trigger-off only when the drain returns -ERESTARTSYS as a +fallback. It implies that each driver should turn off the stream +properly after the drain. Meanwhile, USB-audio MIDI interface didn't +change the port->active flag after the drain. This may leave the +output work picking up the port that is closed right now, which +eventually leads to a use-after-free for the already released rawmidi +object. + +This patch fixes the bug by properly clearing the port->active flag +after the output drain. + +Reported-by: syzbot+70e777a39907d6d5fd0a@syzkaller.appspotmail.com +Cc: +Link: https://lore.kernel.org/r/00000000000011555605dceaff03@google.com +Link: https://lore.kernel.org/r/20220420130247.22062-1-tiwai@suse.de +Signed-off-by: Takashi Iwai +Signed-off-by: Greg Kroah-Hartman +--- + sound/usb/midi.c | 1 + + 1 file changed, 1 insertion(+) + +--- a/sound/usb/midi.c ++++ b/sound/usb/midi.c +@@ -1210,6 +1210,7 @@ static void snd_usbmidi_output_drain(str + } while (drain_urbs && timeout); + finish_wait(&ep->drain_wait, &wait); + } ++ port->active = 0; + spin_unlock_irq(&ep->buffer_lock); + } + diff --git a/queue-4.9/series b/queue-4.9/series index 5d66d16eb51..999d1fecf5b 100644 --- a/queue-4.9/series +++ b/queue-4.9/series @@ -1,3 +1,4 @@ etherdevice-adjust-ether_addr-prototypes-to-silence-wstringop-overead.patch mm-page_alloc-fix-building-error-on-werror-array-compare.patch gfs2-assign-rgrp-glock-before-compute_bitstructs.patch +alsa-usb-audio-clear-midi-port-active-flag-after-draining.patch