Re: [PATCH 5.10 1/1] drm/amdkfd: Check for null pointer after calling kmemdup

[Greg KH]

On Wed, Jan 04, 2023 at 07:56:33PM +0200, Dragos-Marian Panait wrote:
> From: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
> 
> [ Upstream commit abfaf0eee97925905e742aa3b0b72e04a918fa9e ]
> 
> 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@xxxxxxxxxxx>
> Reviewed-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>
> Signed-off-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>
> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
> Signed-off-by: Dragos-Marian Panait <dragos.panait@xxxxxxxxxxxxx>
> ---
>  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 86b4dadf772e..02e3c650ed1c 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c
> @@ -408,6 +408,9 @@ 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;

Not going to queue this up as this is a bogus CVE.