[PATCH 4.19 035/639] mailbox: mediatek: Add check for possible failure of kzalloc

From: Greg Kroah-Hartman
Date: Fri Jan 24 2020 - 06:00:30 EST


From: Houlong Wei <houlong.wei@xxxxxxxxxxxx>

[ Upstream commit 9f0a0a381c5db56e7922dbeea6831f27db58372f ]

The patch 623a6143a845("mailbox: mediatek: Add Mediatek CMDQ driver")
introduce the following static checker warning:
drivers/mailbox/mtk-cmdq-mailbox.c:366 cmdq_mbox_send_data()
error: potential null dereference 'task'. (kzalloc returns null)

Fixes: 623a6143a845 ("mailbox: mediatek: Add Mediatek CMDQ driver")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Houlong Wei <houlong.wei@xxxxxxxxxxxx>
Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Signed-off-by: Jassi Brar <jaswinder.singh@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/mailbox/mtk-cmdq-mailbox.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c
index aec46d5d35061..f7cc29c00302a 100644
--- a/drivers/mailbox/mtk-cmdq-mailbox.c
+++ b/drivers/mailbox/mtk-cmdq-mailbox.c
@@ -363,6 +363,9 @@ static int cmdq_mbox_send_data(struct mbox_chan *chan, void *data)
WARN_ON(cmdq->suspended);

task = kzalloc(sizeof(*task), GFP_ATOMIC);
+ if (!task)
+ return -ENOMEM;
+
task->cmdq = cmdq;
INIT_LIST_HEAD(&task->list_entry);
task->pa_base = pkt->pa_base;
--
2.20.1