smb: client: avoid leaking refcount when cifs_sb_tlink() fails
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.1.189, 5.16, 6.5, 6.6.158, 6.12.111, and 2 more
- 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: smb: client: avoid leaking refcount when cifs_sb_tlink() fails cifs_oplock_break() takes over the reference that cifs_queue_oplock_break() acquired when it queued the work, and drops it with _cifsFileInfo_put() once the break has been processed. Only in setups with "-o multiuser", cifs_sb_tlink() may fail, at which point cifs_oplock_break() returns without putting the file reference, mirroring the reference leak we already fixed in the companion patch to cifs_queue_oplock_break(). This would trigger a crash due to busy inodes on the next unmount: BUG: Dentry ... still in use (1) [unmount of cifs cifs] VFS: Busy inodes after unmount of cifs (cifs) Drop the reference on that path as well. Doing so before the out label mirrors the normal path, which also puts the reference before cifs_done_oplock_break(). Found by Sashiko code review. The failure path was not exercised at runtime.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 5ee28bcfbaacf289eb25c662a2862542ea6ce6a7 · fixed in 55c5f095d4df14271b238f826e1392fda7b6e60e; From e8f5f849ffce24490eb9449e98312b66c0dba76f · fixed in e9c5bcc88b8337157e480c85a6d2f326bc265012; From e8f5f849ffce24490eb9449e98312b66c0dba76f · fixed in 9ec991e148368e3207e98134c509a625097f7693; From e8f5f849ffce24490eb9449e98312b66c0dba76f · fixed in dd03fd658ea59821505e0e643b6b7cbdf51c4e1d; From e8f5f849ffce24490eb9449e98312b66c0dba76f · fixed in 1d1b0f1d812a4011a57bc6c70492c34a2e46c6dd; From e8f5f849ffce24490eb9449e98312b66c0dba76f · fixed in 23b26f4408ac3f35a482d2e5cf6fc865d4201b71; From 6.1.47 · fixed in 6.1.189; From 5.15.128 · fixed in 5.16; From 6.4.12 · fixed in 6.5
- Linux Linux
6.5
- KernelLinux
fixed in 6.1.189; From 6.2.0 · fixed in 6.6.158; From 6.5.0 · fixed in 6.12.111; From 6.7.0 · fixed in 6.18.53; From 6.13.0 · fixed in 7.2.7