3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Johan Hovold <johan@xxxxxxxxxx>
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.Deevi@xxxxxxxxxxxx>
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/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
@@ -1291,6 +1291,9 @@ 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;
@@ -1305,7 +1308,12 @@ static int cx231xx_init_v4l2(struct cx23
}
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);
cx231xx_info("Alternate setting %i, max size= %i\n", i,
dev->video_mode.alt_max_pkt_size[i]);
@@ -1320,6 +1328,9 @@ 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;
@@ -1337,8 +1348,12 @@ static int cx231xx_init_v4l2(struct cx23
}
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);
@@ -1356,6 +1371,9 @@ 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;
@@ -1372,7 +1390,12 @@ static int cx231xx_init_v4l2(struct cx23
}
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);
@@ -1526,6 +1549,11 @@ 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;
@@ -1543,7 +1571,14 @@ 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] =