diff options
| author | Takashi Iwai <tiwai@suse.de> | 2021-05-18 11:39:39 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-05-26 13:06:51 +0300 |
| commit | f42cf1e7b86b4b93179c8891bdb276200bedfa15 (patch) | |
| tree | 0086ddb2ace6fac5e6951eabdf98ae4923ee33f4 /sound/usb/line6/pod.c | |
| parent | 214a9836697c3c75e03b21f2ba4a3818efad1d74 (diff) | |
| download | linux-f42cf1e7b86b4b93179c8891bdb276200bedfa15.tar.xz | |
ALSA: line6: Fix racy initialization of LINE6 MIDI
commit 05ca447630334c323c9e2b788b61133ab75d60d3 upstream.
The initialization of MIDI devices that are found on some LINE6
drivers are currently done in a racy way; namely, the MIDI buffer
instance is allocated and initialized in each private_init callback
while the communication with the interface is already started via
line6_init_cap_control() call before that point. This may lead to
Oops in line6_data_received() when a spurious event is received, as
reported by syzkaller.
This patch moves the MIDI initialization to line6_init_cap_control()
as well instead of the too-lately-called private_init for avoiding the
race. Also this reduces slightly more lines, so it's a win-win
change.
Reported-by: syzbot+0d2b3feb0a2887862e06@syzkallerlkml..appspotmail.com
Link: https://lore.kernel.org/r/000000000000a4be9405c28520de@google.com
Link: https://lore.kernel.org/r/20210517132725.GA50495@hyeyoo
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210518083939.1927-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'sound/usb/line6/pod.c')
| -rw-r--r-- | sound/usb/line6/pod.c | 5 |
1 files changed, 0 insertions, 5 deletions
diff --git a/sound/usb/line6/pod.c b/sound/usb/line6/pod.c index cd44cb5f1310..16e644330c4d 100644 --- a/sound/usb/line6/pod.c +++ b/sound/usb/line6/pod.c @@ -376,11 +376,6 @@ static int pod_init(struct usb_line6 *line6, if (err < 0) return err; - /* initialize MIDI subsystem: */ - err = line6_init_midi(line6); - if (err < 0) - return err; - /* initialize PCM subsystem: */ err = line6_init_pcm(line6, &pod_pcm_properties); if (err < 0) |