CVE-2025-38321: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: smb: Log an error when close_all_cached_dirs fails Under low-memory conditions, close_all_cached_dirs() can't move the dentries to a separate list to dput() them once the locks are dropped. This will result in a "Dentry still in use" error, so add an error message that makes it clear this is what happened: [ 495.281119] CIFS: VFS: \\otters.example.com\share Out of memory while dropping dentries [ 495.281595] ------------[ cut here ]------------ [ 495.281887] BUG: Dentry ffff888115531138{i=78,n=/} still in use (2) [unmount of cifs cifs] [ 495.282391] WARNING: CPU: 1 PID: 2329 at fs/dcache.c:1536 umount_check+0xc8/0xf0 Also, bail out of looping through all tcons as soon as a single allocation fails, since we're already in trouble, and kmalloc() attempts for subseqeuent tcons are likely to fail just like the first one did.

Affected products

• Linux Linux Kernel: before 6.6.95 (fixed in 6.6.95); from 6.7, before 6.12.35 (fixed in 6.12.35); from 6.13, before 6.15.4 (fixed in 6.15.4); version 6.16 only

Published 2025-07-10. Last modified 2026-07-30.