Executive brief
A memory management flaw in the Linux kernel's video for Linux 2 (v4l2) media framework causes a reference to a firmware node object to be leaked when parsing video device links. While the leaked reference is relatively small in scope, repeated calls to the affected function could accumulate unreleased memory references, potentially degrading system performance or contributing to resource exhaustion on embedded devices that rely on v4l2 for camera and video capture functionality.
Technical details
A reference counting leak exists in the v4l2_fwnode_parse_link() function in drivers/media/v4l2-core/v4l2-fwnode.c. The function acquires a remote endpoint fwnode reference via fwnode_graph_get_remote_endpoint() but fails to call fwnode_handle_put() before returning on the success path, though it correctly releases the reference in error paths. The vulnerability is classified as a resource leak (CWE-772). The fix adds a missing fwnode_handle_put() call before the successful return statement. No authentication is required, and the function would be called during normal v4l2 device enumeration and link parsing, which is typically performed automatically by the kernel during device probing.
Affected products
- Linux Linux kernel v4.13 and later (introduced in commit ca50c197bd96, fixed in v7.2 and earlier stable branches)
Timeline
- 2026-09-16: disclosed: CVE-2026-89872 published
- 2026-06-19: patched: Fix originally committed by Biren Pandya
- 2026-09-11: other: Patch merged to stable kernel branches