do_last(): ELOOP failure exit should be done after leaving RCU mode
... or we risk seeing a bogus value of d_is_symlink() there.
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index 65a0e9d..9c590e0 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3211,11 +3211,6 @@
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 {
@@ -3234,6 +3229,10 @@
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;