Fix invalid end handling for SlowBuffer#hexSlice

lib/buffer.js

@@ -42,7 +42,7 @@ SlowBuffer.prototype.hexSlice = function(start, end) {
   var len = this.length;
 
   if (!start || start < 0) start = 0;
-  if (end < 0) end = len - start;
+  if (!end || end < 0 || end > len) end = len - 1;
 
   var out = '';
   for (var i = start; i < end; i ++) {

test/simple/test-buffer.js

@@ -462,3 +462,12 @@ var hexb2 = new Buffer(hexStr, 'hex');
 for (var i = 0; i < 256; i ++) {
   assert.equal(hexb2[i], hexb[i]);
 }
+
+// test an invalid slice end.
+console.log('Try to slice off the end of the buffer');
+var b = new Buffer([1,2,3,4,5]);
+var b2 = b.toString('hex', 1, 10000);
+var b3 = b.toString('hex', 1, 5);
+var b4 = b.toString('hex', 1);
+assert.equal(b2, b3);
+assert.equal(b2, b4);