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author | kib <kib@FreeBSD.org> | 2013-05-21 11:31:56 +0000 |
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committer | kib <kib@FreeBSD.org> | 2013-05-21 11:31:56 +0000 |
commit | e68d3a11b7e0873437e0c75a7a936aa2cf260ac9 (patch) | |
tree | c0eb0e65c450eea3396dac831804c8454c477a8f /sys/fs/nullfs | |
parent | b2b2f0b7824de13c4ff93c389bf00cfa0a78cb38 (diff) | |
download | FreeBSD-src-e68d3a11b7e0873437e0c75a7a936aa2cf260ac9.zip FreeBSD-src-e68d3a11b7e0873437e0c75a7a936aa2cf260ac9.tar.gz |
Do not leak the NULLV_NOUNLOCK flag from the nullfs_unlink_lowervp(),
for the case when the nullfs vnode is not reclaimed. Otherwise, later
reclamation would not unlock the lower vnode.
Reported by: antoine
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Diffstat (limited to 'sys/fs/nullfs')
-rw-r--r-- | sys/fs/nullfs/null_vfsops.c | 26 |
1 files changed, 19 insertions, 7 deletions
diff --git a/sys/fs/nullfs/null_vfsops.c b/sys/fs/nullfs/null_vfsops.c index ad02236..80824a5 100644 --- a/sys/fs/nullfs/null_vfsops.c +++ b/sys/fs/nullfs/null_vfsops.c @@ -409,16 +409,28 @@ nullfs_unlink_lowervp(struct mount *mp, struct vnode *lowervp) vhold(vp); vunref(vp); - /* - * If vunref() dropped the last use reference on the nullfs - * vnode, it must be reclaimed, and its lock was split from - * the lower vnode lock. Need to do extra unlock before - * allowing the final vdrop() to free the vnode. - */ if (vp->v_usecount == 0) { + /* + * If vunref() dropped the last use reference on the + * nullfs vnode, it must be reclaimed, and its lock + * was split from the lower vnode lock. Need to do + * extra unlock before allowing the final vdrop() to + * free the vnode. + */ KASSERT((vp->v_iflag & VI_DOOMED) != 0, - ("not reclaimed %p", vp)); + ("not reclaimed nullfs vnode %p", vp)); VOP_UNLOCK(vp, 0); + } else { + /* + * Otherwise, the nullfs vnode still shares the lock + * with the lower vnode, and must not be unlocked. + * Also clear the NULLV_NOUNLOCK, the flag is not + * relevant for future reclamations. + */ + ASSERT_VOP_ELOCKED(vp, "unlink_lowervp"); + KASSERT((vp->v_iflag & VI_DOOMED) == 0, + ("reclaimed nullfs vnode %p", vp)); + xp->null_flags &= ~NULLV_NOUNLOCK; } vdrop(vp); } |