2023-03-03 10:28:13

by Jason-ch Chen

Subject: [PATCH] remoteproc: mediatek: Dereferencing a pointer that might be NULL

From: jason-ch chen <[email protected]>

The res might be NULL when calling resource_size.

Signed-off-by: jason-ch chen <[email protected]>
---
drivers/remoteproc/mtk_scp.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
index eacdf241f4ef..863d18f63f58 100644
--- a/drivers/remoteproc/mtk_scp.c
+++ b/drivers/remoteproc/mtk_scp.c
@@ -829,6 +829,9 @@ static int scp_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, scp);

res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
+ if (!res)
+ return -ENODEV;
+
scp->sram_base = devm_ioremap_resource(dev, res);
if (IS_ERR((__force void *)scp->sram_base)) {
dev_err(dev, "Failed to parse and map sram memory\n");
--
2.37.3

2023-03-03 18:20:32

by Mathieu Poirier

Subject: Re: [PATCH] remoteproc: mediatek: Dereferencing a pointer that might be NULL

On Fri, 3 Mar 2023 at 03:28, Jason-ch Chen <[email protected]> wrote:
>
> From: jason-ch chen <[email protected]>
>
> The res might be NULL when calling resource_size.
>

"resource_size" ? What is that?

> Signed-off-by: jason-ch chen <[email protected]>
> ---
> drivers/remoteproc/mtk_scp.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
> index eacdf241f4ef..863d18f63f58 100644
> --- a/drivers/remoteproc/mtk_scp.c
> +++ b/drivers/remoteproc/mtk_scp.c
> @@ -829,6 +829,9 @@ static int scp_probe(struct platform_device *pdev)
> platform_set_drvdata(pdev, scp);
>
> res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
> + if (!res)
> + return -ENODEV;
> +

Please have a look at the implementation of devm_ioremap_resource()
along with the function it calls and let me know if your patch is
needed.

> scp->sram_base = devm_ioremap_resource(dev, res);
> if (IS_ERR((__force void *)scp->sram_base)) {
> dev_err(dev, "Failed to parse and map sram memory\n");
> --
> 2.37.3
>

2023-03-09 08:27:02

by Jason-ch Chen

Subject: Re: [PATCH] remoteproc: mediatek: Dereferencing a pointer that might be NULL

Hi Mathieu,

On Fri, 2023-03-03 at 11:20 -0700, Mathieu Poirier wrote:
> On Fri, 3 Mar 2023 at 03:28, Jason-ch Chen <
> [email protected]> wrote:
> >
> > From: jason-ch chen <[email protected]>
> >
> > The res might be NULL when calling resource_size.
> >
>
> "resource_size" ? What is that?
>
> > Signed-off-by: jason-ch chen <[email protected]>
> > ---
> > drivers/remoteproc/mtk_scp.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/remoteproc/mtk_scp.c
> > b/drivers/remoteproc/mtk_scp.c
> > index eacdf241f4ef..863d18f63f58 100644
> > --- a/drivers/remoteproc/mtk_scp.c
> > +++ b/drivers/remoteproc/mtk_scp.c
> > @@ -829,6 +829,9 @@ static int scp_probe(struct platform_device
> > *pdev)
> > platform_set_drvdata(pdev, scp);
> >
> > res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> > "sram");
> > + if (!res)
> > + return -ENODEV;
> > +
>
> Please have a look at the implementation of devm_ioremap_resource()
> along with the function it calls and let me know if your patch is
> needed.
>
Thanks for your reply.
It seems is patch is not needed.
> > scp->sram_base = devm_ioremap_resource(dev, res);
> > if (IS_ERR((__force void *)scp->sram_base)) {
> > dev_err(dev, "Failed to parse and map sram
> > memory\n");
> > --
> > 2.37.3
> >