bpf: fs/xattr: don't assume the inode is locked in path_unlink/path_rmdir
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.18.55, 7.2.9
- 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: bpf: fs/xattr: don't assume the inode is locked in path_unlink/path_rmdir bpf_lsm_has_d_inode_locked() makes the verifier rewrite bpf_[set|remove]_dentry_xattr() to the _locked variants, which assume that the caller already holds the inode's i_rwsem. The path_unlink and path_rmdir hooks are listed, but security_path_unlink() and security_path_rmdir() run before vfs_unlink()/vfs_rmdir() take the victim inode's i_rwsem, so a sleepable BPF LSM program attached to either hook mutates the victim's xattrs without the lock held. Drop the two path hooks from d_inode_locked_hooks so that the verifier keeps the locking bpf_[set|remove]_dentry_xattr() variants, which take the lock themselves.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 56467292794b800164df20c076c409ac548e56ec · fixed in 7504b677c4370c9e4b153c553ff8831c093b1ff6; From 56467292794b800164df20c076c409ac548e56ec · fixed in 640d37fbd34d03af727dbc567f48c0203d1de6b4; From 56467292794b800164df20c076c409ac548e56ec · fixed in 35d442ed1f86465e49df3119fb898f985186db13
- Linux Linux
6.15
- KernelLinux
From 6.15.0 · fixed in 6.18.55; From 6.19.0 · fixed in 7.2.9