goobspatch: Improve sanity checks for invalid patches.

chrome/installer/mac/third_party/bsdiff/goobspatch.c

Index: chrome/installer/mac/third_party/bsdiff/goobspatch.c
diff --git a/chrome/installer/mac/third_party/bsdiff/goobspatch.c b/chrome/installer/mac/third_party/bsdiff/goobspatch.c
index 418f666200735b203e837e29e0d24b4ea887094d..6d7bff4cd8c90fab4a626a978ac19d455f9b1560 100644
--- a/chrome/installer/mac/third_party/bsdiff/goobspatch.c
+++ b/chrome/installer/mac/third_party/bsdiff/goobspatch.c
@@ -3,7 +3,7 @@
  * All rights reserved
  *
  * Redistribution and use in source and binary forms, with or without
- * modification, are permitted providing that the following conditions 
+ * modification, are permitted providing that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ -470,6 +470,10 @@ int main(int argc,char * argv[])
 		};
 
 		/* Sanity-check */
+		if((ctrl[0]<0) || (ctrl[1]<0))
+			errx(1,"corrupt patch (diff): negative chunk size");
+
+		/* Sanity-check */
 		if(newpos+ctrl[0]>newsize)
 			errx(1,"corrupt patch (diff): overrun");