https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=288345
--- Comment #50 from [email protected] --- A commit in branch stable/14 references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=6ed373227680b016b4cfa5af1b802ef23a121513 commit 6ed373227680b016b4cfa5af1b802ef23a121513 Author: Mark Johnston <[email protected]> AuthorDate: 2026-02-25 15:31:30 +0000 Commit: Mark Johnston <[email protected]> CommitDate: 2026-02-26 02:54:34 +0000 nullfs: Fix handling of doomed vnodes in nullfs_unlink_lowervp() nullfs_unlink_lowervp() is called with the lower vnode locked, so the nullfs vnode is locked too. The following can occur: 1. the vunref() call decrements the usecount 2->1, 2. a different thread calls vrele() on the vnode, decrements the usecount 0->1, then blocks on the vnode lock, 3. the first thread tests vp->v_usecount == 0 and observes that it is true, 4. the first thread incorrectly unlocks the lower vnode. Fix this by testing VN_IS_DOOMED directly. Since nullfs_unlink_lowervp() holds the vnode lock, the value of the VIRF_DOOMED flag is stable. Thanks to leres@ for patiently helping to track this down. PR: 288345 MFC after: 1 week Reviewed by: kib Differential Revision: https://reviews.freebsd.org/D55446 (cherry picked from commit 8b64d46fab87af3ae062901312187f3a04ad2d67) sys/fs/nullfs/null_vfsops.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) -- You are receiving this mail because: You are the assignee for the bug.
