4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johan Hovold <johan@xxxxxxxxxx>
commit eacb975b48272f54532b62f515a3cf7eefa35123 upstream.
Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.
Fixes: 2a9f8b5d25be ("V4L/DVB (5206): Usbvision: set alternate interface
modification")
Cc: Thierry MERLE <thierry.merle@xxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/media/usb/usbvision/usbvision-video.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/media/usb/usbvision/usbvision-video.c
+++ b/drivers/media/usb/usbvision/usbvision-video.c
@@ -1523,7 +1523,14 @@ static int usbvision_probe(struct usb_in
}
for (i = 0; i < usbvision->num_alt; i++) {
- u16 tmp = le16_to_cpu(uif->altsetting[i].endpoint[1].desc.
+ u16 tmp;
+
+ if (uif->altsetting[i].desc.bNumEndpoints < 2) {
+ ret = -ENODEV;
+ goto err_pkt;
+ }
+
+ tmp = le16_to_cpu(uif->altsetting[i].endpoint[1].desc.
wMaxPacketSize);
usbvision->alt_max_pkt_size[i] =
(tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1);