[3.13.y-ckt stable] Patch "nfs41: fix nfs4_proc_layoutget error handling" has been added to staging queue

[Kamal Mostafa]

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

    nfs41: fix nfs4_proc_layoutget error handling

to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11-ckt15.

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

For more information about the 3.13.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From affded429c70fbdd7b94b7fda8154110cc20d8bf Mon Sep 17 00:00:00 2001
From: Peng Tao <tao.peng at primarydata.com>
Date: Mon, 17 Nov 2014 11:05:17 +0800
Subject: nfs41: fix nfs4_proc_layoutget error handling

commit 4bd5a980de87d2b5af417485bde97b8eb3d6cf6a upstream.

nfs4_layoutget_release() drops layout hdr refcnt. Grab the refcnt
early so that it is safe to call .release in case nfs4_alloc_pages
fails.

Signed-off-by: Peng Tao <tao.peng at primarydata.com>
Fixes: a47970ff78147 ("NFSv4.1: Hold reference to layout hdr in layoutget")
Signed-off-by: Trond Myklebust <trond.myklebust at primarydata.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 fs/nfs/nfs4proc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index cc27e1f..a9902fb 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7581,6 +7581,9 @@ nfs4_proc_layoutget(struct nfs4_layoutget *lgp, gfp_t gfp_flags)

 	dprintk("--> %s\n", __func__);

+	/* nfs4_layoutget_release calls pnfs_put_layout_hdr */
+	pnfs_get_layout_hdr(NFS_I(inode)->layout);
+
 	lgp->args.layout.pages = nfs4_alloc_pages(max_pages, gfp_flags);
 	if (!lgp->args.layout.pages) {
 		nfs4_layoutget_release(lgp);
@@ -7593,9 +7596,6 @@ nfs4_proc_layoutget(struct nfs4_layoutget *lgp, gfp_t gfp_flags)
 	lgp->res.seq_res.sr_slot = NULL;
 	nfs4_init_sequence(&lgp->args.seq_args, &lgp->res.seq_res, 0);

-	/* nfs4_layoutget_release calls pnfs_put_layout_hdr */
-	pnfs_get_layout_hdr(NFS_I(inode)->layout);
-
 	task = rpc_run_task(&task_setup_data);
 	if (IS_ERR(task))
 		return ERR_CAST(task);
--
1.9.1