From ba5c60fc8f5f574c7cec70740ca19d358b780c57 Mon Sep 17 00:00:00 2001
From: Kumar Amit Mehta <gmate.amit@gmail.com>
Date: Tue, 28 May 2013 00:31:15 -0700
Subject: [PATCH] md: bcache: io.c: fix a potential NULL pointer dereference

commit 5c694129c8db6d89c9be109049a16510b2f70f6d upstream.

bio_alloc_bioset returns NULL on failure. This fix adds a missing check
for potential NULL pointer dereferencing.

Signed-off-by: Kumar Amit Mehta <gmate.amit@gmail.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/md/bcache/io.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c
index 48efd4dea645..d285cd49104c 100644
--- a/drivers/md/bcache/io.c
+++ b/drivers/md/bcache/io.c
@@ -97,6 +97,8 @@ struct bio *bch_bio_split(struct bio *bio, int sectors,
 
 	if (bio->bi_rw & REQ_DISCARD) {
 		ret = bio_alloc_bioset(gfp, 1, bs);
+		if (!ret)
+			return NULL;
 		idx = 0;
 		goto out;
 	}
-- 
2.39.5