ext4: avoid trying to kfree an ERR_PTR pointer

commit a9cfcd63e8d206ce4235c355d857c4fbdf0f4587 upstream.

Thanks to Dan Carpenter for extending smatch to find bugs like this.
(This was found using a development version of smatch.)

Fixes: 36de928641ee48b2078d3fe9514242aaa2f92013
Reported-by: Dan Carpenter <dan.carpenter@oracle.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[lizf: Backported to 3.4:
- s/new.bh/new_bh/
- drop the change to ext4_cross_rename()]
Signed-off-by: Zefan Li <lizefan@huawei.com>
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
index 50992c3..a43e43c 100644
--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -528,6 +528,7 @@
 		bh = bclean(handle, sb, block);
 		if (IS_ERR(bh)) {
 			err = PTR_ERR(bh);
+			bh = NULL;
 			goto out;
 		}
 		if (ext4_bg_has_super(sb, group)) {
@@ -556,6 +557,7 @@
 		bh = bclean(handle, sb, block);
 		if (IS_ERR(bh)) {
 			err = PTR_ERR(bh);
+			bh = NULL;
 			goto out;
 		}