Index: usr.bin/bsdiff/bsdiff/bsdiff.c
===================================================================
--- usr.bin/bsdiff/bsdiff/bsdiff.c
+++ usr.bin/bsdiff/bsdiff/bsdiff.c
@@ -212,7 +212,7 @@
 
 		for(scsc=scan+=len;scan<newsize;scan++) {
 			len=search(I,old,oldsize,new+scan,newsize-scan,
-					0,oldsize,&pos);
+					0,oldsize-1,&pos);
 
 			for(;scsc<scan+len;scsc++)
 			if((scsc+lastoffset<oldsize) &&