From 92782f54c74897b1b8c8eff7191fc66ecf0c1007 Mon Sep 17 00:00:00 2001
From: Rui Xiang <rui.xiang@huawei.com>
Date: Tue, 5 Nov 2013 16:55:02 +1100
Subject: [PATCH] ocfs2: add necessary check in case sb_getblk() fails

sb_getblk() may return an err, so add a check for bh.

Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 fs/ocfs2/refcounttree.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 70d083e60d40..55767e1ba724 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -612,6 +612,11 @@ static int ocfs2_create_refcount_tree(struct inode *inode,
 	}
 
 	new_bh = sb_getblk(inode->i_sb, first_blkno);
+	if (!new_bh) {
+		ret = -ENOMEM;
+		mlog_errno(ret);
+		goto out_commit;
+	}
 	ocfs2_set_new_buffer_uptodate(&new_tree->rf_ci, new_bh);
 
 	ret = ocfs2_journal_access_rb(handle, &new_tree->rf_ci, new_bh,
-- 
2.39.5