[PATCH -next] bcache: Fix potential NULL pointer dereference

[YueHaibing]

There is a potential NULL pointer dereference in case
kzalloc() fails and returns NULL.

Fixes: bc082a55d25c ("bcache: fix inaccurate io state for detached bcache 
devices")
Signed-off-by: YueHaibing <yuehaib...@huawei.com>
---
 drivers/md/bcache/request.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 1507041..a50afa4 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -1094,6 +1094,8 @@ static void detached_dev_do_request(struct bcache_device 
*d, struct bio *bio)
         * which would call closure_get(&dc->disk.cl)
         */
        ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO);
+       if (!ddip)
+               return;
        ddip->d = d;
        ddip->start_time = jiffies;
        ddip->bi_end_io = bio->bi_end_io;
-- 
2.7.0