From 98e37a5c822bdfed2343e6ab9d03680e85783aef Mon Sep 17 00:00:00 2001
From: Thomas Bernard <miniupnp@free.fr>
Date: Mon, 11 Feb 2019 10:05:33 +0100
Subject: [PATCH] (CVE-2018-12900) check that (Tile Width)*(Samples/Pixel) do
 no overflow

fixes bug 2833

(cherry picked from commit 2b0d0e699730d1f26bbeba8397bfdf0e9e01e59d)
---
 tools/tiffcp.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/tiffcp.c b/tools/tiffcp.c
index 489459a7..96f14728 100644
--- a/tools/tiffcp.c
+++ b/tools/tiffcp.c
@@ -43,6 +43,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <limits.h>
 
 #include <ctype.h>
 
@@ -1391,7 +1392,7 @@ DECLAREreadFunc(readSeparateTilesIntoBuffer)
 	int status = 1;
 	uint32 imagew = TIFFRasterScanlineSize(in);
 	uint32 tilew = TIFFTileRowSize(in);
-	int iskew  = imagew - tilew*spp;
+	int iskew;
 	tsize_t tilesize = TIFFTileSize(in);
 	tdata_t tilebuf;
 	uint8* bufp = (uint8*) buf;
@@ -1399,6 +1400,12 @@ DECLAREreadFunc(readSeparateTilesIntoBuffer)
 	uint32 row;
 	uint16 bps = 0, bytes_per_sample;
 
+	if (tilew && spp > (INT_MAX / tilew))
+	{
+		TIFFError(TIFFFileName(in), "Error, cannot handle that much samples per tile row (Tile Width * Samples/Pixel)");
+		return 0;
+	}
+	iskew = imagew - tilew*spp;
 	tilebuf = _TIFFmalloc(tilesize);
 	if (tilebuf == 0)
 		return 0;