[PATCH v2] platform/mellanox: Add some null/error pointer checks to mlxbf-pmc.c

[PATCH v2] platform/mellanox: Add some null/error pointer checks to mlxbf-pmc.c

[Kunwu Chan]

devm_kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.
devm_hwmon_device_register_with_groups return a error pointer upon failure.

Compile-tested only.

Fixes: 1a218d312e65 ("platform/mellanox: mlxbf-pmc: Add Mellanox BlueField PMC driver")
Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Suggested-by: Vadim Pasternak <vadimp@nvidia.com>
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
---
 drivers/platform/mellanox/mlxbf-pmc.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/platform/mellanox/mlxbf-pmc.c b/drivers/platform/mellanox/mlxbf-pmc.c
index 0b427fc24a96..1dd84c7a79de 100644
--- a/drivers/platform/mellanox/mlxbf-pmc.c
+++ b/drivers/platform/mellanox/mlxbf-pmc.c
@@ -1771,6 +1771,8 @@ static int mlxbf_pmc_init_perftype_counter(struct device *dev, int blk_num)
 	attr->dev_attr.show = mlxbf_pmc_event_list_show;
 	attr->nr = blk_num;
 	attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL, "event_list");
+	if (!attr->dev_attr.attr.name)
+		return -ENOMEM;
 	pmc->block[blk_num].block_attr[i] = &attr->dev_attr.attr;
 	attr = NULL;
 
@@ -1784,6 +1786,8 @@ static int mlxbf_pmc_init_perftype_counter(struct device *dev, int blk_num)
 		attr->nr = blk_num;
 		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
 							  "enable");
+		if (!attr->dev_attr.attr.name)
+			return -ENOMEM;
 		pmc->block[blk_num].block_attr[++i] = &attr->dev_attr.attr;
 		attr = NULL;
 	}
@@ -1810,6 +1814,8 @@ static int mlxbf_pmc_init_perftype_counter(struct device *dev, int blk_num)
 		attr->nr = blk_num;
 		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
 							  "counter%d", j);
+		if (!attr->dev_attr.attr.name)
+			return -ENOMEM;
 		pmc->block[blk_num].block_attr[++i] = &attr->dev_attr.attr;
 		attr = NULL;
 
@@ -1821,6 +1827,8 @@ static int mlxbf_pmc_init_perftype_counter(struct device *dev, int blk_num)
 		attr->nr = blk_num;
 		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
 							  "event%d", j);
+		if (!attr->dev_attr.attr.name)
+			return -ENOMEM;
 		pmc->block[blk_num].block_attr[++i] = &attr->dev_attr.attr;
 		attr = NULL;
 	}
@@ -1853,6 +1861,8 @@ static int mlxbf_pmc_init_perftype_reg(struct device *dev, int blk_num)
 		attr->nr = blk_num;
 		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
 							  events[j].evt_name);
+		if (!attr->dev_attr.attr.name)
+			return -ENOMEM;
 		pmc->block[blk_num].block_attr[i] = &attr->dev_attr.attr;
 		attr = NULL;
 		i++;
@@ -1882,6 +1892,8 @@ static int mlxbf_pmc_create_groups(struct device *dev, int blk_num)
 	pmc->block[blk_num].block_attr_grp.attrs = pmc->block[blk_num].block_attr;
 	pmc->block[blk_num].block_attr_grp.name = devm_kasprintf(
 		dev, GFP_KERNEL, pmc->block_name[blk_num]);
+	if (!pmc->block[blk_num].block_attr_grp.name)
+		return -ENOMEM;
 	pmc->groups[pmc->group_num] = &pmc->block[blk_num].block_attr_grp;
 	pmc->group_num++;
 
@@ -2063,6 +2075,8 @@ static int mlxbf_pmc_probe(struct platform_device *pdev)
 
 	pmc->hwmon_dev = devm_hwmon_device_register_with_groups(
 		dev, "bfperf", pmc, pmc->groups);
+	if (IS_ERR(pmc->hwmon_dev))
+		return PTR_ERR(pmc->hwmon_dev);
 	platform_set_drvdata(pdev, pmc);
 
 	return 0;
-- 
2.34.1

RE: [PATCH v2] platform/mellanox: Add some null/error pointer checks to mlxbf-pmc.c

[Vadim Pasternak]

> -----Original Message-----
> From: Kunwu Chan <chentao@kylinos.cn>
> Sent: Friday, 1 December 2023 7:55
> To: hdegoede@redhat.com; ilpo.jarvinen@linux.intel.com; Vadim Pasternak
> <vadimp@nvidia.com>; jdelvare@suse.com; linux@roeck-us.net; Shravan
> Ramani <shravankr@nvidia.com>; jiri@resnulli.us
> Cc: kunwu.chan@hotmail.com; platform-driver-x86@vger.kernel.org; linux-
> kernel@vger.kernel.org; linux-hwmon@vger.kernel.org; Kunwu Chan
> <chentao@kylinos.cn>
> Subject: [PATCH v2] platform/mellanox: Add some null/error pointer checks to
> mlxbf-pmc.c
> 
> devm_kasprintf() returns a pointer to dynamically allocated memory which
> can be NULL upon failure.
> devm_hwmon_device_register_with_groups return a error pointer upon
> failure.
> 
> Compile-tested only.
> 
> Fixes: 1a218d312e65 ("platform/mellanox: mlxbf-pmc: Add Mellanox
> BlueField PMC driver")
> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Suggested-by: Vadim Pasternak <vadimp@nvidia.com>
> Signed-off-by: Kunwu Chan <chentao@kylinos.cn>

Reviewed-by: Vadim Pasternak <vadimp@nvidia.com>

> ---
>  drivers/platform/mellanox/mlxbf-pmc.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/platform/mellanox/mlxbf-pmc.c
> b/drivers/platform/mellanox/mlxbf-pmc.c
> index 0b427fc24a96..1dd84c7a79de 100644
> --- a/drivers/platform/mellanox/mlxbf-pmc.c
> +++ b/drivers/platform/mellanox/mlxbf-pmc.c
> @@ -1771,6 +1771,8 @@ static int mlxbf_pmc_init_perftype_counter(struct
> device *dev, int blk_num)
>  	attr->dev_attr.show = mlxbf_pmc_event_list_show;
>  	attr->nr = blk_num;
>  	attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
> "event_list");
> +	if (!attr->dev_attr.attr.name)
> +		return -ENOMEM;
>  	pmc->block[blk_num].block_attr[i] = &attr->dev_attr.attr;
>  	attr = NULL;
> 
> @@ -1784,6 +1786,8 @@ static int mlxbf_pmc_init_perftype_counter(struct
> device *dev, int blk_num)
>  		attr->nr = blk_num;
>  		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
>  							  "enable");
> +		if (!attr->dev_attr.attr.name)
> +			return -ENOMEM;
>  		pmc->block[blk_num].block_attr[++i] = &attr->dev_attr.attr;
>  		attr = NULL;
>  	}
> @@ -1810,6 +1814,8 @@ static int mlxbf_pmc_init_perftype_counter(struct
> device *dev, int blk_num)
>  		attr->nr = blk_num;
>  		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
>  							  "counter%d", j);
> +		if (!attr->dev_attr.attr.name)
> +			return -ENOMEM;
>  		pmc->block[blk_num].block_attr[++i] = &attr->dev_attr.attr;
>  		attr = NULL;
> 
> @@ -1821,6 +1827,8 @@ static int mlxbf_pmc_init_perftype_counter(struct
> device *dev, int blk_num)
>  		attr->nr = blk_num;
>  		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
>  							  "event%d", j);
> +		if (!attr->dev_attr.attr.name)
> +			return -ENOMEM;
>  		pmc->block[blk_num].block_attr[++i] = &attr->dev_attr.attr;
>  		attr = NULL;
>  	}
> @@ -1853,6 +1861,8 @@ static int mlxbf_pmc_init_perftype_reg(struct
> device *dev, int blk_num)
>  		attr->nr = blk_num;
>  		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
>  							  events[j].evt_name);
> +		if (!attr->dev_attr.attr.name)
> +			return -ENOMEM;
>  		pmc->block[blk_num].block_attr[i] = &attr->dev_attr.attr;
>  		attr = NULL;
>  		i++;
> @@ -1882,6 +1892,8 @@ static int mlxbf_pmc_create_groups(struct device
> *dev, int blk_num)
>  	pmc->block[blk_num].block_attr_grp.attrs = pmc-
> >block[blk_num].block_attr;
>  	pmc->block[blk_num].block_attr_grp.name = devm_kasprintf(
>  		dev, GFP_KERNEL, pmc->block_name[blk_num]);
> +	if (!pmc->block[blk_num].block_attr_grp.name)
> +		return -ENOMEM;
>  	pmc->groups[pmc->group_num] = &pmc-
> >block[blk_num].block_attr_grp;
>  	pmc->group_num++;
> 
> @@ -2063,6 +2075,8 @@ static int mlxbf_pmc_probe(struct platform_device
> *pdev)
> 
>  	pmc->hwmon_dev = devm_hwmon_device_register_with_groups(
>  		dev, "bfperf", pmc, pmc->groups);
> +	if (IS_ERR(pmc->hwmon_dev))
> +		return PTR_ERR(pmc->hwmon_dev);
>  	platform_set_drvdata(pdev, pmc);
> 
>  	return 0;
> --
> 2.34.1

RE: [PATCH v2] platform/mellanox: Add some null/error pointer checks to mlxbf-pmc.c

[Ilpo Järvinen]

[-- Attachment #1: Type: text/plain, Size: 1233 bytes --]

> > Subject: [PATCH v2] platform/mellanox: Add some null/error pointer checks to
> > mlxbf-pmc.c
> > 
> > devm_kasprintf() returns a pointer to dynamically allocated memory which
> > can be NULL upon failure.
> > devm_hwmon_device_register_with_groups return a error pointer upon
> > failure.
> > 
> > Compile-tested only.
> > 
> > Fixes: 1a218d312e65 ("platform/mellanox: mlxbf-pmc: Add Mellanox
> > BlueField PMC driver")
> > Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> > Suggested-by: Vadim Pasternak <vadimp@nvidia.com>
> > Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
> 
> Reviewed-by: Vadim Pasternak <vadimp@nvidia.com>

> >  		attr->dev_attr.attr.name = devm_kasprintf(dev, GFP_KERNEL,
> >  							  "enable");
> > +		if (!attr->dev_attr.attr.name)
> > +			return -ENOMEM;

> >  	pmc->hwmon_dev = devm_hwmon_device_register_with_groups(
> >  		dev, "bfperf", pmc, pmc->groups);
> > +	if (IS_ERR(pmc->hwmon_dev))
> > +		return PTR_ERR(pmc->hwmon_dev);

Thank you both, applied to review-ilpo and will go into fixes branch once 
LKP has had its chance to build this.

In the end, I decided to split the devm_kasprintf() and 
devm_hwmon_device_register_with_groups() changes into separate commits.

-- 
 i.