As the possible failure of the allocation, kmemdup() may return NULL
pointer.
Therefore, it should be better to check the 'props2' in order to prevent
the dereference of NULL pointer.

Fixes: 3a87177eb141 ("drm/amdkfd: Add topology support for dGPUs")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
index c60e82697385..d15380c65c6d 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
@@ -410,6 +410,9 @@ static int kfd_parse_subtype_iolink(struct crat_subtype_iolink *iolink,
 			return -ENODEV;
 		/* same everything but the other direction */
 		props2 = kmemdup(props, sizeof(*props2), GFP_KERNEL);
+		if (!props2)
+			return -ENOMEM;
+
 		props2->node_from = id_to;
 		props2->node_to = id_from;
 		props2->kobj = NULL;
-- 
2.25.1

Am 2022-01-05 um 4:09 a.m. schrieb Jiasheng Jiang:
> As the possible failure of the allocation, kmemdup() may return NULL
> pointer.
> Therefore, it should be better to check the 'props2' in order to prevent
> the dereference of NULL pointer.
>
> Fixes: 3a87177eb141 ("drm/amdkfd: Add topology support for dGPUs")
> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>

Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>


> ---
>  drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
> index c60e82697385..d15380c65c6d 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
> @@ -410,6 +410,9 @@ static int kfd_parse_subtype_iolink(struct crat_subtype_iolink *iolink,
>  			return -ENODEV;
>  		/* same everything but the other direction */
>  		props2 = kmemdup(props, sizeof(*props2), GFP_KERNEL);
> +		if (!props2)
> +			return -ENOMEM;
> +
>  		props2->node_from = id_to;
>  		props2->node_to = id_from;
>  		props2->kobj = NULL;

On 2022-01-05 10:56 a.m., Felix Kuehling wrote:
> Am 2022-01-05 um 4:09 a.m. schrieb Jiasheng Jiang:
>> As the possible failure of the allocation, kmemdup() may return NULL
>> pointer.
>> Therefore, it should be better to check the 'props2' in order to prevent
>> the dereference of NULL pointer.
>>
>> Fixes: 3a87177eb141 ("drm/amdkfd: Add topology support for dGPUs")
>> Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
> Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
I applied the patch to amd-staging-drm-next.

Regards,
   Felix


>
>> ---
>>   drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
>> index c60e82697385..d15380c65c6d 100644
>> --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
>> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
>> @@ -410,6 +410,9 @@ static int kfd_parse_subtype_iolink(struct crat_subtype_iolink *iolink,
>>   			return -ENODEV;
>>   		/* same everything but the other direction */
>>   		props2 = kmemdup(props, sizeof(*props2), GFP_KERNEL);
>> +		if (!props2)
>> +			return -ENOMEM;
>> +
>>   		props2->node_from = id_to;
>>   		props2->node_to = id_from;
>>   		props2->kobj = NULL;