[PATCHv3] drm: zynqmp_dp: Fix integer overflow in zynqmp_dp_rate_get()

[Tomi Valkeinen]

Hi,

On 15/12/2024 14:53, Karol Przybylski wrote:
> This patch fixes a potential integer overflow in the zynqmp_dp_rate_get()
> 
> The issue comes up when the expression
> drm_dp_bw_code_to_link_rate(dp->test.bw_code) * 10000 is evaluated using 32-bit
> Now the constant is a compatible 64-bit type.
> 
> Resolves coverity issues: CID 1636340 and CID 1635811
> 
> Cc: stable at vger.kernel.org
> Fixes: 28edaacb821c6 ("drm: zynqmp_dp: Add debugfs interface for compliance testing")
> Signed-off-by: Karol Przybylski <karprzy7 at gmail.com>
> ---
> Changes from previous versions:
> Added Fixes tag
> Added Cc for stable kernel version
> Fixed formatting
> 
>   drivers/gpu/drm/xlnx/zynqmp_dp.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c b/drivers/gpu/drm/xlnx/zynqmp_dp.c
> index 25c5dc61ee88..56a261a40ea3 100644
> --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c
> +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c
> @@ -2190,7 +2190,7 @@ static int zynqmp_dp_rate_get(void *data, u64 *val)
>   	struct zynqmp_dp *dp = data;
>   
>   	mutex_lock(&dp->lock);
> -	*val = drm_dp_bw_code_to_link_rate(dp->test.bw_code) * 10000;
> +	*val = drm_dp_bw_code_to_link_rate(dp->test.bw_code) * 10000ULL;
>   	mutex_unlock(&dp->lock);
>   	return 0;
>   }

Thanks, pushed to drm-misc-next.

  Tomi