CVEvulnerability
CVE-2026-89879
- Status
- Received
- Published
- 2026-09-16
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
media: s2255: bound JPEG frame size before copying into the buffer
s2255_fillbuff() memcpy()s vc->jpg_size bytes of a captured JPEG/MJPEG
frame into the vb2 plane. vc->jpg_size is taken verbatim from the
S2255_MARKER_FRAME header the device sends (pdword[4] in save_frame())
and, unlike the frame payload length just above it, is never bounded:
payload = le32_to_cpu(pdword[3]);
if (payload > vc->req_image_size) /* payload is checked ... */
return -EINVAL;
vc->pkt_size = payload;
vc->jpg_size = le32_to_cpu(pdword[4]); /* ... jpg_size is not */
A malicious or malfunctioning device can therefore report a jpg_size
larger than the destination vb2 plane, and the memcpy() writes past it.
jpg_size is a signed int, so a value with the top bit set also turns
into a huge length.
Reject a frame whose jpg_size is negative or exceeds the plane size
before copying it.
References
- https://git.kernel.org/stable/c/2542516a147bfad740e7e411c251b639fad260ff git.kernel.org
- https://git.kernel.org/stable/c/32a595dd3e8634544e5cfbc47f906dff3d3c1ef8 git.kernel.org
- https://git.kernel.org/stable/c/4b6f7bccc6559ae5c54573c284fe76eafc9989b2 git.kernel.org
- https://git.kernel.org/stable/c/68d664f1b4efe525e99154b7058fcb0378bdaff7 git.kernel.org
- https://git.kernel.org/stable/c/79f58f900dd221ab04ea74bf4eaf79fa3b0fcc77 git.kernel.org
- https://git.kernel.org/stable/c/d2ecaaab6a4f165abb54cdf61be60030b5782bf8 git.kernel.org
- https://git.kernel.org/stable/c/dd739517560c8d0ec4463a53e717bf40b988d7da git.kernel.org
- https://git.kernel.org/stable/c/e504cc888f42999dd76b6a43788c422610f2aad2 git.kernel.org