NFSD: Prevent client use-after-free during NFSv4.0 revoked-state cleanup
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.12.109, 6.18.50, 7.2.4
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: NFSD: Prevent client use-after-free during NFSv4.0 revoked-state cleanup nfs40_clean_admin_revoked() takes a stateid reference under clp->cl_lock, drops nn->client_lock, and calls nfsd4_drop_revoked_stid(), which dereferences the stateid's client through s->sc_client->cl_lock. The stateid reference does not pin the client, so a teardown racing the dropped lock can free the client while nfsd4_drop_revoked_stid() is still using it. This cleanup runs from the laundromat, so a periodic sweep can race force_expire_client() driven by a write to the clients/<id>/ctl file. Skip a client that is already expiring and otherwise pin it with cl_rpc_users under client_lock before dropping the lock, matching nfsd4_revoke_states().
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From d688d8585e6bea5e4e37f7497feea93b6b0a469c · fixed in 0ae0d2b5c5a1b39c0b3c15d96b32a5b0c583d519; From d688d8585e6bea5e4e37f7497feea93b6b0a469c · fixed in b413ec5b23e3445dc9c4f273116078e2d4747626; From d688d8585e6bea5e4e37f7497feea93b6b0a469c · fixed in 81cf7f1413862f87b078920c838460a6a88aa030; From d688d8585e6bea5e4e37f7497feea93b6b0a469c · fixed in 7b4f8a1586c42d3afc3c0ac779af2db7ab1a5c55
- Linux Linux
6.9
- KernelLinux
From 6.9.0 · fixed in 6.12.109; From 6.13.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4