From 447d6275f0c21f6cc97a88b3a0c601436a4cdf2a Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 15 Mar 2016 15:20:58 +0100 Subject: ALSA: usb-audio: Add sanity checks for endpoint accesses Add some sanity check codes before actually accessing the endpoint via get_endpoint() in order to avoid the invalid access through a malformed USB descriptor. Mostly just checking bNumEndpoints, but in one place (snd_microii_spdif_default_get()), the validity of iface and altsetting index is checked as well. Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=971125 Cc: Signed-off-by: Takashi Iwai --- sound/usb/mixer_quirks.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'sound/usb/mixer_quirks.c') diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c index 279025650568..f6c3bf79af9a 100644 --- a/sound/usb/mixer_quirks.c +++ b/sound/usb/mixer_quirks.c @@ -1519,7 +1519,11 @@ static int snd_microii_spdif_default_get(struct snd_kcontrol *kcontrol, /* use known values for that card: interface#1 altsetting#1 */ iface = usb_ifnum_to_if(chip->dev, 1); + if (!iface || iface->num_altsetting < 2) + return -EINVAL; alts = &iface->altsetting[1]; + if (get_iface_desc(alts)->bNumEndpoints < 1) + return -EINVAL; ep = get_endpoint(alts, 0)->bEndpointAddress; err = snd_usb_ctl_msg(chip->dev, -- cgit v1.2.1