[3.11.y.z extended stable] Patch "NFSv4: Fix state reference counting in" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    NFSv4: Fix state reference counting in

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 968ee3aa3e2b908e10d784fe5e404812cd740509 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <Trond.Myklebust at netapp.com>
Date: Mon, 28 Oct 2013 14:57:12 -0400
Subject: NFSv4: Fix state reference counting in
 _nfs4_opendata_reclaim_to_nfs4_state

commit d49f042aeec99c5f87160bb52dd52088b1051311 upstream.

Currently, if the call to nfs_refresh_inode fails, then we end up leaking
a reference count, due to the call to nfs4_get_open_state.
While we're at it, replace nfs4_get_open_state with a simple call to
atomic_inc(); there is no need to do a full lookup of the struct nfs_state
since it is passed as an argument in the struct nfs4_opendata, and
is already assigned to the variable 'state'.

Signed-off-by: Trond Myklebust <Trond.Myklebust at netapp.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/nfs/nfs4proc.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 84c6225..9960a5b 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1236,11 +1236,6 @@ _nfs4_opendata_reclaim_to_nfs4_state(struct nfs4_opendata *data)
 		goto err;
 	}

-	ret = -ENOMEM;
-	state = nfs4_get_open_state(inode, data->owner);
-	if (state == NULL)
-		goto err;
-
 	ret = nfs_refresh_inode(inode, &data->f_attr);
 	if (ret)
 		goto err;
@@ -1251,6 +1246,7 @@ _nfs4_opendata_reclaim_to_nfs4_state(struct nfs4_opendata *data)
 		nfs4_opendata_check_deleg(data, state);
 	update_open_stateid(state, &data->o_res.stateid, NULL,
 			    data->o_arg.fmode);
+	atomic_inc(&state->count);

 	return state;
 err:
--
1.8.3.2