diff --git a/third_party/agg23/agg_clip_liang_barsky.h b/third_party/agg23/agg_clip_liang_barsky.h index db6ca97..5b1261f 100644 --- a/third_party/agg23/agg_clip_liang_barsky.h +++ b/third_party/agg23/agg_clip_liang_barsky.h @@ -20,6 +20,7 @@ #ifndef AGG_CLIP_LIANG_BARSKY_INCLUDED #define AGG_CLIP_LIANG_BARSKY_INCLUDED #include "agg_basics.h" +#include "third_party/base/numerics/safe_math.h" namespace agg { template<class T> @@ -36,8 +37,18 @@ inline unsigned clip_liang_barsky(T x1, T y1, T x2, T y2, T* x, T* y) { const FX_FLOAT nearzero = 1e-30f; - FX_FLOAT deltax = (FX_FLOAT)(x2 - x1); - FX_FLOAT deltay = (FX_FLOAT)(y2 - y1); + + pdfium::base::CheckedNumeric<FX_FLOAT> width = x2; + width -= x1; + if (!width.IsValid()) + return 0; + pdfium::base::CheckedNumeric<FX_FLOAT> height = y2; + height -= y1; + if (!height.IsValid()) + return 0; + + FX_FLOAT deltax = width.ValueOrDefault(0); + FX_FLOAT deltay = height.ValueOrDefault(0); unsigned np = 0; if(deltax == 0) { deltax = (x1 > clip_box.x1) ? -nearzero : nearzero;