From: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Date: Wed, 28 Aug 2019 17:01:22 +0900
Subject: [PATCH] NFS: direct.c: Fix memory leak of dreq when
 nfs_get_lock_context fails
Git-commit: 8605cf0e852af3b2c771c18417499dc4ceed03d5
Patch-mainline: v5.7
References: git-fixes

When dreq is allocated by nfs_direct_req_alloc(), dreq->kref is
initialized to 2. Therefore we need to call nfs_direct_req_release()
twice to release the allocated dreq. Usually it is called in
nfs_file_direct_{read, write}() and nfs_direct_complete().

However, current code only calls nfs_direct_req_relese() once if
nfs_get_lock_context() fails in nfs_file_direct_{read, write}().
So, that case would result in memory leak.

Fix this by adding the missing call.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Acked-by: NeilBrown <neilb@suse.com>

---
 fs/nfs/direct.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -600,6 +600,7 @@ ssize_t nfs_file_direct_read(struct kioc
 	l_ctx = nfs_get_lock_context(dreq->ctx);
 	if (IS_ERR(l_ctx)) {
 		result = PTR_ERR(l_ctx);
+		nfs_direct_req_release(dreq);
 		goto out_release;
 	}
 	dreq->l_ctx = l_ctx;
@@ -1024,6 +1025,7 @@ ssize_t nfs_file_direct_write(struct kio
 	l_ctx = nfs_get_lock_context(dreq->ctx);
 	if (IS_ERR(l_ctx)) {
 		result = PTR_ERR(l_ctx);
+		nfs_direct_req_release(dreq);
 		goto out_release;
 	}
 	dreq->l_ctx = l_ctx;