From: Zheyu Ma <zheyuma97@gmail.com> stable inclusion from stable-v4.19.256 commit 5e7338f4dd92b2f8915a82abfa1dd3ad3464bea0 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICG792 CVE: CVE-2022-50229 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit ffb2759df7efbc00187bfd9d1072434a13a54139 upstream. When the driver fails in snd_card_register() at probe time, it will free the 'bcd2k->midi_out_urb' before killing it, which may cause a UAF bug. The following log can reveal it: [ 50.727020] BUG: KASAN: use-after-free in bcd2000_input_complete+0x1f1/0x2e0 [snd_bcd2000] [ 50.727623] Read of size 8 at addr ffff88810fab0e88 by task swapper/4/0 [ 50.729530] Call Trace: [ 50.732899] bcd2000_input_complete+0x1f1/0x2e0 [snd_bcd2000] Fix this by adding usb_kill_urb() before usb_free_urb(). Fixes: b47a22290d58 ("ALSA: MIDI driver for Behringer BCD2000 USB device") Signed-off-by: Zheyu Ma <zheyuma97@gmail.com> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20220715010515.2087925-1-zheyuma97@gmail.com Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Wang Tao <wangtao554@huawei.com> --- sound/usb/bcd2000/bcd2000.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sound/usb/bcd2000/bcd2000.c b/sound/usb/bcd2000/bcd2000.c index d6c8b29fe430..bdab5426aa17 100644 --- a/sound/usb/bcd2000/bcd2000.c +++ b/sound/usb/bcd2000/bcd2000.c @@ -357,7 +357,8 @@ static int bcd2000_init_midi(struct bcd2000 *bcd2k) static void bcd2000_free_usb_related_resources(struct bcd2000 *bcd2k, struct usb_interface *interface) { - /* usb_kill_urb not necessary, urb is aborted automatically */ + usb_kill_urb(bcd2k->midi_out_urb); + usb_kill_urb(bcd2k->midi_in_urb); usb_free_urb(bcd2k->midi_out_urb); usb_free_urb(bcd2k->midi_in_urb); -- 2.34.1