In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: ASSERT when failing to find index by plane/stream id [WHY] finddispcfgidxbyplaneid and finddispcfgidxbystreamid returns an array index and they return -1 when not found; however, -1 is not a valid index number. [HOW] When this happens, call ASSERT(), and return a positive number (which is fewer than callers' array size) instead. This fixes 4 OVERRUN and 2 NEGATIVE_RETURNS issues reported by Coverity.