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| author | Takashi Iwai <tiwai@suse.de> | 2017-10-09 15:51:23 +0300 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2017-10-09 17:17:18 +0300 |
| commit | c95072b3d88fac4be295815f2b67df366c0c297f (patch) | |
| tree | 67ae0944d91885f8ac4078829918c19d5b555544 /sound/usb/line6/driver.c | |
| parent | 54a4b2b45817ea2365b40c923c098a26af0c0dbb (diff) | |
| download | linux-c95072b3d88fac4be295815f2b67df366c0c297f.tar.xz | |
ALSA: line6: Fix leftover URB at error-path during probe
While line6_probe() may kick off URB for a control MIDI endpoint, the
function doesn't clean up it properly at its error path. This results
in a leftover URB action that is eventually triggered later and causes
an Oops like:
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 0 Comm: swapper/1 Not tainted
RIP: 0010:usb_fill_bulk_urb ./include/linux/usb.h:1619
RIP: 0010:line6_start_listen+0x3fe/0x9e0 sound/usb/line6/driver.c:76
Call Trace:
<IRQ>
line6_data_received+0x1f7/0x470 sound/usb/line6/driver.c:326
__usb_hcd_giveback_urb+0x2e0/0x650 drivers/usb/core/hcd.c:1779
usb_hcd_giveback_urb+0x337/0x420 drivers/usb/core/hcd.c:1845
dummy_timer+0xba9/0x39f0 drivers/usb/gadget/udc/dummy_hcd.c:1965
call_timer_fn+0x2a2/0x940 kernel/time/timer.c:1281
....
Since the whole clean-up procedure is done in line6_disconnect()
callback, we can simply call it in the error path instead of
open-coding the whole again. It'll fix such an issue automagically.
The bug was spotted by syzkaller.
Fixes: eedd0e95d355 ("ALSA: line6: Don't forget to call driver's destructor at error path")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/line6/driver.c')
| -rw-r--r-- | sound/usb/line6/driver.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c index 0ff5a7d2e19f..c8f723c3a033 100644 --- a/sound/usb/line6/driver.c +++ b/sound/usb/line6/driver.c @@ -779,9 +779,10 @@ int line6_probe(struct usb_interface *interface, return 0; error: - if (line6->disconnect) - line6->disconnect(line6); - snd_card_free(card); + /* we can call disconnect callback here because no close-sync is + * needed yet at this point + */ + line6_disconnect(interface); return ret; } EXPORT_SYMBOL_GPL(line6_probe); |