[PATCH 4.11 191/197] NFSv4: Fix an rcu lock leak

[Greg Kroah-Hartman]

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

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

From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>

commit 2e84611b3f4fa50e1f4c12f2966fcc7fb955d944 upstream.

The intention in the original patch was to release the lock when
we put the inode, however something got screwed up.

Reported-by: Jason Yan <yanaijie@xxxxxxxxxx>
Fixes: 7b410d9ce460f ("pNFS: Delay getting the layout header in..")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 fs/nfs/callback_proc.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -131,10 +131,11 @@ restart:
 			if (!inode)
 				continue;
 			if (!nfs_sb_active(inode->i_sb)) {
-				rcu_read_lock();
+				rcu_read_unlock();
 				spin_unlock(&clp->cl_lock);
 				iput(inode);
 				spin_lock(&clp->cl_lock);
+				rcu_read_lock();
 				goto restart;
 			}
 			return inode;
@@ -170,10 +171,11 @@ restart:
 			if (!inode)
 				continue;
 			if (!nfs_sb_active(inode->i_sb)) {
-				rcu_read_lock();
+				rcu_read_unlock();
 				spin_unlock(&clp->cl_lock);
 				iput(inode);
 				spin_lock(&clp->cl_lock);
+				rcu_read_lock();
 				goto restart;
 			}
 			return inode;