Executive brief
A vulnerability was identified in the Linux kernel's AFS (Andrew File System) implementation regarding how it handles symbolic links. This flaw could lead to memory leaks or data inconsistencies when multiple processes attempt to access or update the same symbolic link simultaneously. In a business environment, this could result in system instability or unexpected behavior in applications relying on AFS network storage.
Technical details
The AFS filesystem implementation in the Linux kernel fails to implement proper locking within the afs_get_link() function. Specifically, it lacks locking around afs_read_single(), which allows races between concurrent get_link() calls that can result in memory leaks. Additionally, the implementation fails to use RCU barriering when accessing buffer pointers during RCU pathwalks and is susceptible to race conditions if a third party updates symlink contents on the server. The fix involves introducing validate_lock around read operations, implementing a separate RCU-managed copy of symlink contents with proper refcounting, and isolating symlink handling logic from directory routines.
Affected products
- Linux Linux 6.14, 7.0.11, 7.1
Timeline
- 2026-07-19: advisory: CVE-2026-64057 published by NVD
- 2026-06-01: patched: Fix committed to Linux stable tree