Bug 2554949 (CVE-2026-98543) - CVE-2026-98543 kernel: bpf: fs/xattr: don't assume the inode is locked in path_unlink/path_rmdir
Summary: CVE-2026-98543 kernel: bpf: fs/xattr: don't assume the inode is locked in pat...
Keywords:
Status: NEW
Alias: CVE-2026-98543
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-10-18 15:34 UTC by OSIDB Bzimport
Modified: 2026-10-19 23:10 UTC (History)
17 users (show)

Fixed In Version:
Clone Of:
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Description OSIDB Bzimport 2026-10-18 15:34:50 UTC
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.


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