[PATCH 4.4 318/342] do_last(): ELOOP failure exit should be done after leaving RCU mode

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Al Viro <v...@zeniv.linux.org.uk>

commit 5129fa482b16615fd4464d2f5d23acb1b7056c66 upstream.

... or we risk seeing a bogus value of d_is_symlink() there.

Signed-off-by: Al Viro <v...@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 fs/namei.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3149,11 +3149,6 @@ finish_lookup:
        if (unlikely(error))
                return error;
 
-       if (unlikely(d_is_symlink(path.dentry)) && !(open_flag & O_PATH)) {
-               path_to_nameidata(&path, nd);
-               return -ELOOP;
-       }
-
        if ((nd->flags & LOOKUP_RCU) || nd->path.mnt != path.mnt) {
                path_to_nameidata(&path, nd);
        } else {
@@ -3172,6 +3167,10 @@ finish_open:
                return error;
        }
        audit_inode(nd->name, nd->path.dentry, 0);
+       if (unlikely(d_is_symlink(nd->path.dentry)) && !(open_flag & O_PATH)) {
+               error = -ELOOP;
+               goto out;
+       }
        error = -EISDIR;
        if ((open_flag & O_CREAT) && d_is_dir(nd->path.dentry))
                goto out;