Fix mountpoint reference leakage in linkat

commit d22e6338db7f613dd4f6095c190682fcc519e4b7 upstream.

Recent changes to retry on ESTALE in linkat
(commit 442e31ca5a49e398351b2954b51f578353fdf210)
introduced a mountpoint reference leak and a small memory
leak in case a filesystem link operation returns ESTALE
which is pretty normal for distributed filesystems like
lustre, nfs and so on.
Free old_path in such a case.

[AV: there was another missing path_put() nearby - on the previous
goto retry]

[js: the second path_put is not in 3.12 yet, hunk removed]

Signed-off-by: Oleg Drokin: <green@linuxhacker.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 23ac50f..187cacf 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3924,6 +3924,7 @@ retry:
 out_dput:
 	done_path_create(&new_path, new_dentry);
 	if (retry_estale(error, how)) {
+		path_put(&old_path);
 		how |= LOOKUP_REVAL;
 		goto retry;
 	}