diff --git a/src/lazy/SkLazyPixelRef.cpp b/src/lazy/SkLazyPixelRef.cpp
index c0d5d90..c262884 100644
--- a/src/lazy/SkLazyPixelRef.cpp
+++ b/src/lazy/SkLazyPixelRef.cpp
@@ -49,7 +49,7 @@
     Sk64 safeSize;
     safeSize.setZero();
     if (info.fHeight > 0) {
-        safeSize.setMul(info.fHeight, *rowBytes);
+        safeSize.setMul(info.fHeight, SkToS32(*rowBytes));
     }
     SkASSERT(!safeSize.isNeg());
     return safeSize.is32() ? safeSize.get32() : 0;