2018-08-21 10:25:24

by houlong wei

Subject: [PATCH] mailbox: mediatek: Add check for possible failure of kzalloc

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 <[email protected]>
Signed-off-by: Houlong Wei <[email protected]>
---
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 aec46d5..f7cc29c 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;
--
1.7.9.5

2018-08-21 15:07:47

by Philipp Zabel

Subject: Re: [PATCH] mailbox: mediatek: Add check for possible failure of kzalloc

On Tue, 2018-08-21 at 18:22 +0800, Houlong Wei wrote:
> 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 <[email protected]>
> Signed-off-by: Houlong Wei <[email protected]>
> ---
> 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 aec46d5..f7cc29c 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;

Reviewed-by: Philipp Zabel <[email protected]>

regards
Philipp