From: Al Viro viro@zeniv.linux.org.uk
commit 4f0ed93fb92d3528c73c80317509df3f800a222b upstream.
That (and traversals in case of umount .) should be done before complete_walk(). Either a braino or mismerge damage on queue reorders - either way, I should've spotted that much earlier.
Fucked-up-by: Al Viro viro@zeniv.linux.org.uk X-Paperbag: Brown Fixes: 161aff1d93ab "LOOKUP_MOUNTPOINT: fold path_mountpointat() into path_lookupat()" Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/namei.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/fs/namei.c +++ b/fs/namei.c @@ -2328,16 +2328,16 @@ static int path_lookupat(struct nameidat while (!(err = link_path_walk(s, nd)) && (s = lookup_last(nd)) != NULL) ; + if (!err && unlikely(nd->flags & LOOKUP_MOUNTPOINT)) { + err = handle_lookup_down(nd); + nd->flags &= ~LOOKUP_JUMPED; // no d_weak_revalidate(), please... + } if (!err) err = complete_walk(nd);
if (!err && nd->flags & LOOKUP_DIRECTORY) if (!d_can_lookup(nd->path.dentry)) err = -ENOTDIR; - if (!err && unlikely(nd->flags & LOOKUP_MOUNTPOINT)) { - err = handle_lookup_down(nd); - nd->flags &= ~LOOKUP_JUMPED; // no d_weak_revalidate(), please... - } if (!err) { *path = nd->path; nd->path.mnt = NULL;