4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johan Hovold <jo...@kernel.org>
commit 0cd273bb5e4d1828efaaa8dfd11b7928131ed149 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: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver")
Cc: Sri Deevi <srinivasa.de...@conexant.com>
Signed-off-by: Johan Hovold <jo...@kernel.org>
Signed-off-by: Hans Verkuil <hans.verk...@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mche...@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/media/usb/cx231xx/cx231xx-cards.c | 45 ++++++++++++++++++++++++++----
1 file changed, 40 insertions(+), 5 deletions(-)
--- a/drivers/media/usb/cx231xx/cx231xx-cards.c
+++ b/drivers/media/usb/cx231xx/cx231xx-cards.c
@@ -1397,6 +1397,9 @@ static int cx231xx_init_v4l2(struct cx23
uif = udev->actconfig->interface[idx];
+ if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1)
+ return -ENODEV;
+
dev->video_mode.end_point_addr =
uif->altsetting[0].endpoint[isoc_pipe].desc.bEndpointAddress;
dev->video_mode.num_alt = uif->num_altsetting;
@@ -1410,7 +1413,12 @@ static int cx231xx_init_v4l2(struct cx23
return -ENOMEM;
for (i = 0; i < dev->video_mode.num_alt; i++) {
- u16 tmp =
le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc.wMaxPacketSize);
+ u16 tmp;
+
+ if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1)
+ return -ENODEV;
+
+ tmp =
le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].desc.wMaxPacketSize);
dev->video_mode.alt_max_pkt_size[i] = (tmp & 0x07ff) * (((tmp &
0x1800) >> 11) + 1);
dev_dbg(dev->dev,
"Alternate setting %i, max size= %i\n", i,
@@ -1427,6 +1435,9 @@ static int cx231xx_init_v4l2(struct cx23
}
uif = udev->actconfig->interface[idx];
+ if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1)
+ return -ENODEV;
+
dev->vbi_mode.end_point_addr =
uif->altsetting[0].endpoint[isoc_pipe].desc.
bEndpointAddress;
@@ -1443,8 +1454,12 @@ static int cx231xx_init_v4l2(struct cx23
return -ENOMEM;
for (i = 0; i < dev->vbi_mode.num_alt; i++) {
- u16 tmp =
- le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].
+ u16 tmp;
+
+ if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1)
+ return -ENODEV;
+
+ tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].
desc.wMaxPacketSize);
dev->vbi_mode.alt_max_pkt_size[i] =
(tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1);
@@ -1464,6 +1479,9 @@ static int cx231xx_init_v4l2(struct cx23
}
uif = udev->actconfig->interface[idx];
+ if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1)
+ return -ENODEV;
+
dev->sliced_cc_mode.end_point_addr =
uif->altsetting[0].endpoint[isoc_pipe].desc.
bEndpointAddress;
@@ -1478,7 +1496,12 @@ static int cx231xx_init_v4l2(struct cx23
return -ENOMEM;
for (i = 0; i < dev->sliced_cc_mode.num_alt; i++) {
- u16 tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].
+ u16 tmp;
+
+ if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe + 1)
+ return -ENODEV;
+
+ tmp = le16_to_cpu(uif->altsetting[i].endpoint[isoc_pipe].
desc.wMaxPacketSize);
dev->sliced_cc_mode.alt_max_pkt_size[i] =
(tmp & 0x07ff) * (((tmp & 0x1800) >> 11) + 1);
@@ -1647,6 +1670,11 @@ static int cx231xx_usb_probe(struct usb_
}
uif = udev->actconfig->interface[idx];
+ if (uif->altsetting[0].desc.bNumEndpoints < isoc_pipe + 1) {
+ retval = -ENODEV;
+ goto err_video_alt;
+ }
+
dev->ts1_mode.end_point_addr =
uif->altsetting[0].endpoint[isoc_pipe].
desc.bEndpointAddress;
@@ -1664,7 +1692,14 @@ static int cx231xx_usb_probe(struct usb_
}
for (i = 0; i < dev->ts1_mode.num_alt; i++) {
- u16 tmp = le16_to_cpu(uif->altsetting[i].
+ u16 tmp;
+
+ if (uif->altsetting[i].desc.bNumEndpoints < isoc_pipe +
1) {
+ retval = -ENODEV;
+ goto err_video_alt;
+ }
+
+ tmp = le16_to_cpu(uif->altsetting[i].
endpoint[isoc_pipe].desc.
wMaxPacketSize);
dev->ts1_mode.alt_max_pkt_size[i] =
