Re: [PATCH V1] accel/amdxdna: Fix an integer overflow in aie2_query_ctx_status_array()

["Falkowski, Maciej" <maciej.falkowski@linux.intel.com>]

Reviewed-by: Maciej Falkowski <maciej.falkowski@linux.intel.com>

On 9/9/2025 5:45 PM, Lizhi Hou wrote:
> The unpublished smatch static checker reported a warning.
>
> drivers/accel/amdxdna/aie2_pci.c:904 aie2_query_ctx_status_array()
> warn: potential user controlled sizeof overflow
> 'args->num_element * args->element_size' '1-u32max(user) * 1-u32max(user)'
>
> Even this will not cause a real issue, it is better to put a reasonable
> limitation for element_size and num_element. Add condition to make sure
> the input element_size <= 4K and num_element <= 1K.
>
> Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> Closes: https://lore.kernel.org/dri-devel/aL56ZCLyl3tLQM1e@stanley.mountain/
> Fixes: 2f509fe6a42c ("accel/amdxdna: Add ioctl DRM_IOCTL_AMDXDNA_GET_ARRAY")
> Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
> ---
>   drivers/accel/amdxdna/aie2_pci.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/drivers/accel/amdxdna/aie2_pci.c b/drivers/accel/amdxdna/aie2_pci.c
> index 87c425e3d2b9..6e39c769bb6d 100644
> --- a/drivers/accel/amdxdna/aie2_pci.c
> +++ b/drivers/accel/amdxdna/aie2_pci.c
> @@ -898,6 +898,12 @@ static int aie2_query_ctx_status_array(struct amdxdna_client *client,
>   
>   	drm_WARN_ON(&xdna->ddev, !mutex_is_locked(&xdna->dev_lock));
>   
> +	if (args->element_size > SZ_4K || args->num_element > SZ_1K) {
> +		XDNA_DBG(xdna, "Invalid element size %d or number of element %d",
> +			 args->element_size, args->num_element);
> +		return -EINVAL;
> +	}
> +
>   	array_args.element_size = min(args->element_size,
>   				      sizeof(struct amdxdna_drm_hwctx_entry));
>   	array_args.buffer = args->buffer;