From: Bhuvanesh Surachari <bhuvanesh_surachari@mentor.com>
Date: Mon, 1 Dec 2014 07:23:02 +0000 (-0500)
Subject: mmc: queue: Improve error handling during allocation of bounce buffers
X-Git-Tag: firefly_0821_release~176^2~2782^2~3
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fdb409f636cd6fc3ac4e2f9c880402860e738554;p=firefly-linux-kernel-4.4.55.git

mmc: queue: Improve error handling during allocation of bounce buffers

Allocation of previous bounce buffer in mmc_init_queue when the current
bounce buffer allocation fails was leading to a crash later in
__blk_segment_map_sg. Error handling is improved by allocating previous
bounce buffer only if the current bounce buffer allocation succeeds.

Signed-off-by: Bhuvanesh Surachari <bhuvanesh_surachari@mentor.com>
Signed-off-by: Harish Jenny K N <harish_kandiga@mentor.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
---

diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index cfa6110632c3..236d194c2883 100644
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -232,13 +232,15 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
 			if (!mqrq_cur->bounce_buf) {
 				pr_warn("%s: unable to allocate bounce cur buffer\n",
 					mmc_card_name(card));
-			}
-			mqrq_prev->bounce_buf = kmalloc(bouncesz, GFP_KERNEL);
-			if (!mqrq_prev->bounce_buf) {
-				pr_warn("%s: unable to allocate bounce prev buffer\n",
-					mmc_card_name(card));
-				kfree(mqrq_cur->bounce_buf);
-				mqrq_cur->bounce_buf = NULL;
+			} else {
+				mqrq_prev->bounce_buf =
+						kmalloc(bouncesz, GFP_KERNEL);
+				if (!mqrq_prev->bounce_buf) {
+					pr_warn("%s: unable to allocate bounce prev buffer\n",
+						mmc_card_name(card));
+					kfree(mqrq_cur->bounce_buf);
+					mqrq_cur->bounce_buf = NULL;
+				}
 			}
 		}