smb: client: pin DFS superblock in iterator callback
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.6.158, 6.12.111, 6.18.53, 7.2.7
- 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: pin DFS superblock in iterator callback tcon_super_cb() stores a raw superblock pointer, but __cifs_get_super() takes its active reference only after iterate_supers_type() has dropped s_umount and its passive reference. Concurrent DFS automount expiry can therefore free the superblock before cifs_sb_active() uses it. A deterministic KASAN test reproduces the race as: BUG: KASAN: slab-use-after-free in cifs_sb_active+0x77/0x80 The same test passes with this change applied. Take the active reference in the callback while iterate_supers_type() still holds s_umount shared. cifs_put_tcp_super() remains the matching release.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From bacd704a95ad0b93af995aae4a523aa046f46563 · fixed in 3c9acc9835c304013a4faeb969fe9333d66ca9f8; From bacd704a95ad0b93af995aae4a523aa046f46563 · fixed in ea43a15cea36dc5ddd832be5bddeac7dd804cbcf; From bacd704a95ad0b93af995aae4a523aa046f46563 · fixed in a6b6561522212af852c9ad8a7dca8d59ef2c7377; From bacd704a95ad0b93af995aae4a523aa046f46563 · fixed in 5b01a8c0209690db75341528ec53fd87e0ac1460; From bacd704a95ad0b93af995aae4a523aa046f46563 · fixed in d806d5a85dcbe2a0f181b2f0f9f61ddfbefa1818
- Linux Linux
5.7
- KernelLinux
From 5.7.0 · fixed in 6.6.158; From 6.7.0 · fixed in 6.12.111; From 6.13.0 · fixed in 6.18.53; From 6.19.0 · fixed in 7.2.7