[3.16.y-ckt stable] Patch "pNFS: Fix a memory leak when attempted pnfs fails" has been added to staging queue

[Luis Henriques]

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

    pNFS: Fix a memory leak when attempted pnfs fails

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-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 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 934220acd3aefe1b48576b091ae592d88cfb586d Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust at primarydata.com>
Date: Wed, 17 Jun 2015 19:41:51 -0400
Subject: pNFS: Fix a memory leak when attempted pnfs fails

commit 1ca018d28d96d07788474abf66a5f3e9594841f5 upstream.

pnfs_do_write() expects the call to pnfs_write_through_mds() to free the
pgio header and to release the layout segment before exiting. The problem
is that nfs_pgio_data_destroy() doesn't actually do this; it only frees
the memory allocated by nfs_generic_pgio().

Ditto for pnfs_do_read()...

Fix in both cases is to add a call to hdr->release(hdr).

Signed-off-by: Trond Myklebust <trond.myklebust at primarydata.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/nfs/pnfs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index dea11c2c8c1e..77498f9ba554 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1558,6 +1558,7 @@ pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
 		desc->pg_recoalesce = 1;
 	}
 	nfs_pgio_data_destroy(hdr);
+	hdr->release(hdr);
 }

 static enum pnfs_try_status
@@ -1695,6 +1696,7 @@ pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
 		desc->pg_recoalesce = 1;
 	}
 	nfs_pgio_data_destroy(hdr);
+	hdr->release(hdr);
 }

 /*