diff options
author | Johan Hovold <johan@kernel.org> | 2019-12-20 10:31:34 +0100 |
---|---|---|
committer | Takashi Iwai <tiwai@suse.de> | 2019-12-20 11:31:46 +0100 |
commit | 0141254b0a74b37aa7eb13d42a56adba84d51c73 (patch) | |
tree | 1095e51d158b7daa9faa3bc6080d22feff6ffd03 | |
parent | 66c5d718e5a6f80153b5e8d6ad8ba8e9c3320839 (diff) |
ALSA: usb-audio: fix set_format altsetting sanity check
Make sure to check the return value of usb_altnum_to_altsetting() to
avoid dereferencing a NULL pointer when the requested alternate settings
is missing.
The format altsetting number may come from a quirk table and there does
not seem to be any other validation of it (the corresponding index is
checked however).
Fixes: b099b9693d23 ("ALSA: usb-audio: Avoid superfluous usb_set_interface() calls")
Cc: stable <stable@vger.kernel.org> # 4.18
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191220093134.1248-1-johan@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
-rw-r--r-- | sound/usb/pcm.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index 96298c767c76..a11c8150af58 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -506,9 +506,9 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt) if (WARN_ON(!iface)) return -EINVAL; alts = usb_altnum_to_altsetting(iface, fmt->altsetting); - altsd = get_iface_desc(alts); - if (WARN_ON(altsd->bAlternateSetting != fmt->altsetting)) + if (WARN_ON(!alts)) return -EINVAL; + altsd = get_iface_desc(alts); if (fmt == subs->cur_audiofmt && !subs->need_setup_fmt) return 0; |