NFS: LOOKUP_DIRECTORY is also ok with symlinks
authorTrond Myklebust <trond.myklebust@hammerspace.com>
Tue, 8 Feb 2022 18:38:23 +0000 (13:38 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 23 Feb 2022 10:57:35 +0000 (11:57 +0100)
commit e0caaf75d443e02e55e146fd75fe2efc8aed5540 upstream.

Commit ac795161c936 (NFSv4: Handle case where the lookup of a directory
fails) [1], part of Linux since 5.17-rc2, introduced a regression, where
a symbolic link on an NFS mount to a directory on another NFS does not
resolve(?) the first time it is accessed:

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Fixes: ac795161c936 ("NFSv4: Handle case where the lookup of a directory fails")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Tested-by: Donald Buczek <buczek@molgen.mpg.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/nfs/dir.c

index c3ae37036b9d13f120deeb5d4d42a7cb1eee5e60..c702bcad59e39c92cb268108d5430deb87588cee 100644 (file)
@@ -1610,14 +1610,14 @@ no_open:
        if (!res) {
                inode = d_inode(dentry);
                if ((lookup_flags & LOOKUP_DIRECTORY) && inode &&
-                   !S_ISDIR(inode->i_mode))
+                   !(S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
                        res = ERR_PTR(-ENOTDIR);
                else if (inode && S_ISREG(inode->i_mode))
                        res = ERR_PTR(-EOPENSTALE);
        } else if (!IS_ERR(res)) {
                inode = d_inode(res);
                if ((lookup_flags & LOOKUP_DIRECTORY) && inode &&
-                   !S_ISDIR(inode->i_mode)) {
+                   !(S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) {
                        dput(res);
                        res = ERR_PTR(-ENOTDIR);
                } else if (inode && S_ISREG(inode->i_mode)) {