[PATCH 3.19.y-ckt 136/251] pNFS: Fix a memory leak when attempted pnfs fails

[Kamal Mostafa]

3.19.8-ckt4 -stable review patch.  If anyone has any objections, please let me know.

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

From: Trond Myklebust <trond.myklebust at primarydata.com>

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: Kamal Mostafa <kamal 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 883ee88..2b39287 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1576,6 +1576,7 @@ 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
@@ -1692,6 +1693,7 @@ pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
 		desc->pg_recoalesce = 1;
 	}
 	nfs_pgio_data_destroy(hdr);
+	hdr->release(hdr);
 }
 
 /*
-- 
1.9.1