On 2018-03-13 02:28 AM, Shirish S wrote:
> This patch adds an essential check related to the size of the
> payload to be transferred via aux channel.
>
> Without this check dal_ddc_service_read_dpcd_data() is fed with
> inappropriate payload size leading to deadlocks.
>
> Signed-off-by: Shirish S <shirish.s at amd.com>
Reviewed-by: Harry Wentland <harry.wentland at amd.com>
Harry
> ---
> drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> index 39cfe0f..8291d74 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> @@ -85,6 +85,9 @@ static ssize_t dm_dp_aux_transfer(struct drm_dp_aux *aux,
> enum ddc_result res;
> ssize_t read_bytes;
>
> + if (WARN_ON(msg->size > 16))
> + return -E2BIG;
> +
> switch (msg->request & ~DP_AUX_I2C_MOT) {
> case DP_AUX_NATIVE_READ:
> read_bytes = dal_ddc_service_read_dpcd_data(
>
