diff --git a/libtiff/tif_getimage.c b/libtiff/tif_getimage.c
index 0c47564..6db0a4b 100644
--- a/libtiff/tif_getimage.c
+++ b/libtiff/tif_getimage.c
@@ -673,18 +673,24 @@ gtTileSeparate(TIFFRGBAImage* img, uint32* raster, uint32 w, uint32 h)
 	unsigned char* p2;
 	unsigned char* pa;
 	tsize_t tilesize;
+	tsize_t bufsize;
 	int32 fromskew, toskew;
 	int alpha = img->alpha;
 	uint32 nrow;
 	int ret = 1, flip;
 
 	tilesize = TIFFTileSize(tif);
-	buf = (unsigned char*) _TIFFmalloc((alpha?4:3)*tilesize);
+	bufsize = TIFFSafeMultiply(tsize_t,alpha?4:3,tilesize);
+	if (bufsize == 0) {
+		TIFFErrorExt(tif->tif_clientdata, TIFFFileName(tif), "Integer overflow in %s", "gtTileSeparate");
+		return (0);
+	}
+	buf = (unsigned char*) _TIFFmalloc(bufsize);
 	if (buf == 0) {
 		TIFFErrorExt(tif->tif_clientdata, TIFFFileName(tif), "No space for tile buffer");
 		return (0);
 	}
-	_TIFFmemset(buf, 0, (alpha?4:3)*tilesize);
+	_TIFFmemset(buf, 0, bufsize);
 	p0 = buf;
 	p1 = p0 + tilesize;
 	p2 = p1 + tilesize;
@@ -880,17 +886,23 @@ gtStripSeparate(TIFFRGBAImage* img, uint32* raster, uint32 w, uint32 h)
 	uint32 rowsperstrip, offset_row;
 	uint32 imagewidth = img->width;
 	tsize_t stripsize;
+	tsize_t bufsize;
 	int32 fromskew, toskew;
 	int alpha = img->alpha;
 	int ret = 1, flip;
 
 	stripsize = TIFFStripSize(tif);
-	p0 = buf = (unsigned char *)_TIFFmalloc((alpha?4:3)*stripsize);
+	bufsize = TIFFSafeMultiply(tsize_t,alpha?4:3,stripsize);
+	if (bufsize == 0) {
+		TIFFErrorExt(tif->tif_clientdata, TIFFFileName(tif), "Integer overflow in %s", "gtStripSeparate");
+		return (0);
+	}
+	p0 = buf = (unsigned char *)_TIFFmalloc(bufsize);
 	if (buf == 0) {
 		TIFFErrorExt(tif->tif_clientdata, TIFFFileName(tif), "No space for tile buffer");
 		return (0);
 	}
-	_TIFFmemset(buf, 0, (alpha?4:3)*stripsize);
+	_TIFFmemset(buf, 0, bufsize);
 	p1 = p0 + stripsize;
 	p2 = p1 + stripsize;
 	pa = (alpha?(p2+stripsize):NULL);
diff --git a/libtiff/tiffiop.h b/libtiff/tiffiop.h
index a064039..b8fa5c4 100644
--- a/libtiff/tiffiop.h
+++ b/libtiff/tiffiop.h
@@ -243,7 +243,7 @@ struct tiff {
 #define	TIFFroundup(x, y) (TIFFhowmany(x,y)*(y))
 
 /* Safe multiply which returns zero if there is an integer overflow */
-#define TIFFSafeMultiply(t,v,m) ((((t)m != (t)0) && (((t)((v*m)/m)) == (t)v)) ? (t)(v*m) : (t)0)
+#define TIFFSafeMultiply(t,v,m) ((((t)(m) != (t)0) && (((t)(((v)*(m))/(m))) == (t)(v))) ? (t)((v)*(m)) : (t)0)
 
 #define TIFFmax(A,B) ((A)>(B)?(A):(B))
 #define TIFFmin(A,B) ((A)<(B)?(A):(B))