[PATCH net v2] net: mvpp2: fix possible invalid pointer dereference

[PATCH net v2] net: mvpp2: fix possible invalid pointer dereference

[Hui Tang]

It will cause invalid pointer dereference to priv->cm3_base behind,
if PTR_ERR(priv->cm3_base) in mvpp2_get_sram().

Fixes: a59d354208a7 ("net: mvpp2: enable global flow control")
Signed-off-by: Hui Tang <tanghui20@huawei.com>
---
v1 -> v2: patch title include target
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index d98f7e9a480e..c92bd1922421 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -7421,7 +7421,7 @@ static int mvpp2_probe(struct platform_device *pdev)
 			dev_warn(&pdev->dev, "Fail to alloc CM3 SRAM\n");
 
 		/* Enable global Flow Control only if handler to SRAM not NULL */
-		if (priv->cm3_base)
+		if (!IS_ERR_OR_NULL(priv->cm3_base))
 			priv->global_tx_fc = true;
 	}
 
-- 
2.17.1

Re: [PATCH net v2] net: mvpp2: fix possible invalid pointer dereference

[Marcin Wojtas]

wt., 15 lis 2022 o 10:08 Hui Tang <tanghui20@huawei.com> napisał(a):
>
> It will cause invalid pointer dereference to priv->cm3_base behind,
> if PTR_ERR(priv->cm3_base) in mvpp2_get_sram().
>
> Fixes: a59d354208a7 ("net: mvpp2: enable global flow control")
> Signed-off-by: Hui Tang <tanghui20@huawei.com>
> ---
> v1 -> v2: patch title include target
> ---
>  drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> index d98f7e9a480e..c92bd1922421 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> @@ -7421,7 +7421,7 @@ static int mvpp2_probe(struct platform_device *pdev)
>                         dev_warn(&pdev->dev, "Fail to alloc CM3 SRAM\n");
>
>                 /* Enable global Flow Control only if handler to SRAM not NULL */
> -               if (priv->cm3_base)
> +               if (!IS_ERR_OR_NULL(priv->cm3_base))
>                         priv->global_tx_fc = true;
>         }
>
> --
> 2.17.1
>

Thank you for the patch.

Reviewed-by: Marcin Wojtas <mw@semihalf.com>

Best regards,
Marcin

Re: [PATCH net v2] net: mvpp2: fix possible invalid pointer dereference

[Andrew Lunn]

On Tue, Nov 15, 2022 at 05:04:33PM +0800, Hui Tang wrote:
> It will cause invalid pointer dereference to priv->cm3_base behind,
> if PTR_ERR(priv->cm3_base) in mvpp2_get_sram().

As i pointed out for the MDIO driver, i wonder if this is the correct
fix. mvpp2_get_sram() is probably a better place to handle this

In fact, please add a devm_ioremap_resource_optional() which returns
NULL if the resource does not exist, or an error code for real errors,
and make drivers fail the probe on real errors.

	Andrew

[PATCH net v3] net: mvpp2: fix possible invalid pointer dereference

[Hui Tang]

It will cause invalid pointer dereference to priv->cm3_base behind,
if PTR_ERR(priv->cm3_base) in mvpp2_get_sram().

Fixes: a59d354208a7 ("net: mvpp2: enable global flow control")
Signed-off-by: Hui Tang <tanghui20@huawei.com>
---
v1 -> v2: patch title include target
v2 -> v3: keep priv->cm3_base NULL if devm_ioremap_resource() failed
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index d98f7e9a480e..9c3fbb153b5b 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -7349,6 +7349,7 @@ static int mvpp2_get_sram(struct platform_device *pdev,
 			  struct mvpp2 *priv)
 {
 	struct resource *res;
+	void __iomem *base;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
 	if (!res) {
@@ -7359,9 +7360,11 @@ static int mvpp2_get_sram(struct platform_device *pdev,
 		return 0;
 	}
 
-	priv->cm3_base = devm_ioremap_resource(&pdev->dev, res);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (!IS_ERR(priv->cm3_base))
+		priv->cm3_base = base;
 
-	return PTR_ERR_OR_ZERO(priv->cm3_base);
+	return PTR_ERR_OR_ZERO(base);
 }
 
 static int mvpp2_probe(struct platform_device *pdev)
-- 
2.17.1

[PATCH net v4] net: mvpp2: fix possible invalid pointer dereference

[Hui Tang]

It will cause invalid pointer dereference to priv->cm3_base behind,
if PTR_ERR(priv->cm3_base) in mvpp2_get_sram().

Fixes: a59d354208a7 ("net: mvpp2: enable global flow control")
Signed-off-by: Hui Tang <tanghui20@huawei.com>
---
v1 -> v2: patch title include target
v2 -> v3: keep priv->cm3_base NULL if devm_ioremap_resource() failed
v3 -> v4: change if (priv->cm3_base) to if (base)
---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index d98f7e9a480e..efb582b63640 100644
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -7349,6 +7349,7 @@ static int mvpp2_get_sram(struct platform_device *pdev,
 			  struct mvpp2 *priv)
 {
 	struct resource *res;
+	void __iomem *base;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
 	if (!res) {
@@ -7359,9 +7360,11 @@ static int mvpp2_get_sram(struct platform_device *pdev,
 		return 0;
 	}
 
-	priv->cm3_base = devm_ioremap_resource(&pdev->dev, res);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (!IS_ERR(base))
+		priv->cm3_base = base;
 
-	return PTR_ERR_OR_ZERO(priv->cm3_base);
+	return PTR_ERR_OR_ZERO(base);
 }
 
 static int mvpp2_probe(struct platform_device *pdev)
-- 
2.17.1

Re: [PATCH net v4] net: mvpp2: fix possible invalid pointer dereference

[Jakub Kicinski]

On Wed, 16 Nov 2022 10:14:37 +0800 Hui Tang wrote:
> It will cause invalid pointer dereference to priv->cm3_base behind,
> if PTR_ERR(priv->cm3_base) in mvpp2_get_sram().
> 
> Fixes: a59d354208a7 ("net: mvpp2: enable global flow control")
> Signed-off-by: Hui Tang <tanghui20@huawei.com>

Please do not repost new versions so often:

https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#tl-dr

do not use --in-reply-to

> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> index d98f7e9a480e..efb582b63640 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> @@ -7349,6 +7349,7 @@ static int mvpp2_get_sram(struct platform_device *pdev,
>  			  struct mvpp2 *priv)
>  {
>  	struct resource *res;
> +	void __iomem *base;
>  
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
>  	if (!res) {
> @@ -7359,9 +7360,11 @@ static int mvpp2_get_sram(struct platform_device *pdev,
>  		return 0;
>  	}
>  
> -	priv->cm3_base = devm_ioremap_resource(&pdev->dev, res);
> +	base = devm_ioremap_resource(&pdev->dev, res);
> +	if (!IS_ERR(base))
> +		priv->cm3_base = base;
>  
> -	return PTR_ERR_OR_ZERO(priv->cm3_base);
> +	return PTR_ERR_OR_ZERO(base);

Use the idiomatic error handling, keep success path un-indented:

	ptr = function();
	if (IS_ERR(ptr))
		return PTR_ERR(ptr);

	priv->bla = ptr;
	return 0;
	

Re: [PATCH net v4] net: mvpp2: fix possible invalid pointer dereference

[Hui Tang]

On 2022/11/16 12:28, Jakub Kicinski wrote:
> On Wed, 16 Nov 2022 10:14:37 +0800 Hui Tang wrote:
>> It will cause invalid pointer dereference to priv->cm3_base behind,
>> if PTR_ERR(priv->cm3_base) in mvpp2_get_sram().
>>
>> Fixes: a59d354208a7 ("net: mvpp2: enable global flow control")
>> Signed-off-by: Hui Tang <tanghui20@huawei.com>
>
> Please do not repost new versions so often:
>
> https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#tl-dr
>
> do not use --in-reply-to

Thanks for pointing out, but should I resend it with [PATCH net v3]  or [PATCH net v5]?

>> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
>> index d98f7e9a480e..efb582b63640 100644
>> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
>> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
>> @@ -7349,6 +7349,7 @@ static int mvpp2_get_sram(struct platform_device *pdev,
>>  			  struct mvpp2 *priv)
>>  {
>>  	struct resource *res;
>> +	void __iomem *base;
>>
>>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
>>  	if (!res) {
>> @@ -7359,9 +7360,11 @@ static int mvpp2_get_sram(struct platform_device *pdev,
>>  		return 0;
>>  	}
>>
>> -	priv->cm3_base = devm_ioremap_resource(&pdev->dev, res);
>> +	base = devm_ioremap_resource(&pdev->dev, res);
>> +	if (!IS_ERR(base))
>> +		priv->cm3_base = base;
>>
>> -	return PTR_ERR_OR_ZERO(priv->cm3_base);
>> +	return PTR_ERR_OR_ZERO(base);
>
> Use the idiomatic error handling, keep success path un-indented:
>
> 	ptr = function();
> 	if (IS_ERR(ptr))
> 		return PTR_ERR(ptr);
>
> 	priv->bla = ptr;
> 	return 0;
> 	
>
Ok, I will fix it in next version

Re: [PATCH net v4] net: mvpp2: fix possible invalid pointer dereference

[Andrew Lunn]

> Thanks for pointing out, but should I resend it with [PATCH net v3]
> or [PATCH net v5]?

The number should always increment. It is how we tell older versions
from newer versions.

     Andrew