2016-03-06 01:21:37

by Vladimir Zapolskiy

Subject: [PATCH] mailbox: sti: fix check of error code returned by devm_ioremap_resource()

The change fixes potential oops while accessing iomem on invalid
address, if devm_ioremap_resource() fails due to some reason.

The devm_ioremap_resource() function returns ERR_PTR() and never
returns NULL, which makes useless a following check for NULL.

Signed-off-by: Vladimir Zapolskiy <[email protected]>
Fixes: 9ef4546cbd7e ("mailbox: Add support for ST's Mailbox IP")
---
drivers/mailbox/mailbox-sti.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mailbox/mailbox-sti.c b/drivers/mailbox/mailbox-sti.c
index 2394cfe..a334db5 100644
--- a/drivers/mailbox/mailbox-sti.c
+++ b/drivers/mailbox/mailbox-sti.c
@@ -430,8 +430,8 @@ static int sti_mbox_probe(struct platform_device *pdev)

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mdev->base = devm_ioremap_resource(&pdev->dev, res);
- if (!mdev->base)
- return -ENOMEM;
+ if (IS_ERR(mdev->base))
+ return PTR_ERR(mdev->base);

ret = of_property_read_string(np, "mbox-name", &mdev->name);
if (ret)
--
2.1.4

2016-03-06 03:01:11

by Lee Jones

Subject: Re: [PATCH] mailbox: sti: fix check of error code returned by devm_ioremap_resource()

On Sun, 06 Mar 2016, Vladimir Zapolskiy wrote:

> The change fixes potential oops while accessing iomem on invalid
> address, if devm_ioremap_resource() fails due to some reason.
>
> The devm_ioremap_resource() function returns ERR_PTR() and never
> returns NULL, which makes useless a following check for NULL.
>
> Signed-off-by: Vladimir Zapolskiy <[email protected]>
> Fixes: 9ef4546cbd7e ("mailbox: Add support for ST's Mailbox IP")
> ---
> drivers/mailbox/mailbox-sti.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)

Acked-by: Lee Jones <[email protected]>

> diff --git a/drivers/mailbox/mailbox-sti.c b/drivers/mailbox/mailbox-sti.c
> index 2394cfe..a334db5 100644
> --- a/drivers/mailbox/mailbox-sti.c
> +++ b/drivers/mailbox/mailbox-sti.c
> @@ -430,8 +430,8 @@ static int sti_mbox_probe(struct platform_device *pdev)
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> mdev->base = devm_ioremap_resource(&pdev->dev, res);
> - if (!mdev->base)
> - return -ENOMEM;
> + if (IS_ERR(mdev->base))
> + return PTR_ERR(mdev->base);
>
> ret = of_property_read_string(np, "mbox-name", &mdev->name);
> if (ret)

--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
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