smb: Log an error when close_all_cached_dirs fails

Summary

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.

Timeline

1. Jul 10, 2025, 8:14 AM UTCCVE published
2. Oct 15, 2026, 9:49 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. Oct 15, 2026, 9:52 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 73934e535cffbda1490fa97d82690a0f9aa73e94 · fixed in b8ced2b9a23a1a2c1e0ed8d0d02512e51bdf38da; From 548812afd96982a76a93ba76c0582ea670c40d9e · fixed in 43f26094d6702e494e800532c3f1606e7a68eb30; From 3fa640d035e5ae526769615c35cb9ed4be6e3662 · fixed in 4479db143390bdcadc1561292aab579cdfa9f6c6; From 3fa640d035e5ae526769615c35cb9ed4be6e3662 · fixed in a2182743a8b4969481f64aec4908ff162e8a206c; From 6.6.64 · fixed in 6.6.95; From 6.12.2 · fixed in 6.12.35; From 6.11.11 · fixed in 6.12

• Linux Linux

  6.13

• KernelLinux

  fixed in 6.6.95; From 6.7.0 · fixed in 6.12.35; From 6.13.0 · fixed in 6.15.4

References 4