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: stable@vger.kernel.org Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/usb/clock.c | 2 ++ sound/usb/endpoint.c | 3 +++ sound/usb/mixer_quirks.c | 4 ++++ sound/usb/pcm.c | 2 ++ 4 files changed, 11 insertions(+)
diff --git a/sound/usb/clock.c b/sound/usb/clock.c index 2ed260b10f6d..7ccbcaf6a147 100644 --- a/sound/usb/clock.c +++ b/sound/usb/clock.c @@ -285,6 +285,8 @@ static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface, unsigned char data[3]; int err, crate;
+ if (get_iface_desc(alts)->bNumEndpoints < 1) + return -EINVAL; ep = get_endpoint(alts, 0)->bEndpointAddress;
/* if endpoint doesn't have sampling rate control, bail out */ diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index 7b1cb365ffab..c07a7eda42a2 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -438,6 +438,9 @@ exit_clear: * * New endpoints will be added to chip->ep_list and must be freed by * calling snd_usb_endpoint_free(). + * + * For SND_USB_ENDPOINT_TYPE_SYNC, the caller needs to guarantee that + * bNumEndpoints > 1 beforehand. */ struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip, struct usb_host_interface *alts, 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, diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c index 9245f52d43bd..44d178ee9177 100644 --- a/sound/usb/pcm.c +++ b/sound/usb/pcm.c @@ -159,6 +159,8 @@ static int init_pitch_v1(struct snd_usb_audio *chip, int iface, unsigned char data[1]; int err;
+ if (get_iface_desc(alts)->bNumEndpoints < 1) + return -EINVAL; ep = get_endpoint(alts, 0)->bEndpointAddress;
data[0] = 1;