|  | diff --git a/third_party/libopenjpeg20/j2k.c b/third_party/libopenjpeg20/j2k.c | 
|  | index b20f219..9056feb 100644 | 
|  | --- a/third_party/libopenjpeg20/j2k.c | 
|  | +++ b/third_party/libopenjpeg20/j2k.c | 
|  | @@ -8211,6 +8211,12 @@ static OPJ_BOOL opj_j2k_update_image_data (opj_tcd_t * p_tcd, OPJ_BYTE * p_data, | 
|  | * */ | 
|  | assert( l_res->x0 >= 0); | 
|  | assert( l_res->x1 >= 0); | 
|  | + | 
|  | +                /* Prevent bad casting to unsigned values in the subsequent lines. */ | 
|  | +                if ( l_res->x0 < 0 || l_res->x1 < 0 || l_res->y0 < 0 || l_res->y1 < 0 ) { | 
|  | +                        return OPJ_FALSE; | 
|  | +                } | 
|  | + | 
|  | if ( l_x0_dest < (OPJ_UINT32)l_res->x0 ) { | 
|  | l_start_x_dest = (OPJ_UINT32)l_res->x0 - l_x0_dest; | 
|  | l_offset_x0_src = 0; |