diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index fe72245fb9ca..2ca1f2e9712c 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -880,7 +880,7 @@ static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx
 		goto fail_len;
 	repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx];
 	idx++;
-	if (idx > raw->curlen)
+	if (idx + repmsg->u.remote_dpcd_read_ack.num_bytes > raw->curlen)
 		goto fail_len;
 
 	memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes);
@@ -916,7 +916,9 @@ static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg
 		goto fail_len;
 	repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx];
 	idx++;
-	/* TODO check */
+	if (idx + repmsg->u.remote_i2c_read_ack.num_bytes > raw->curlen)
+		goto fail_len;
+
 	memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes);
 	return true;
 fail_len: