Fix OOB write in --print-code.

R=jkummerow@chromium.org
BUG=v8:2624

Review URL: https://chromiumcodereview.appspot.com/14018010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14267 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/disassembler.cc

@@ -107,7 +107,6 @@ static void DumpBuffer(FILE* f, StringBuilder* out) {
 }
 
 
-
 static const int kOutBufferSize = 2048 + String::kMaxShortPrintLength;
 static const int kRelocInfoPosition = 57;
 

src/utils.cc

@@ -46,7 +46,7 @@ void SimpleStringBuilder::AddString(const char* s) {
 
 
 void SimpleStringBuilder::AddSubstring(const char* s, int n) {
-  ASSERT(!is_finalized() && position_ + n < buffer_.length());
+  ASSERT(!is_finalized() && position_ + n <= buffer_.length());
   ASSERT(static_cast<size_t>(n) <= strlen(s));
   memcpy(&buffer_[position_], s, n * kCharSize);
   position_ += n;
@@ -79,7 +79,13 @@ void SimpleStringBuilder::AddDecimalInteger(int32_t value) {
 
 
 char* SimpleStringBuilder::Finalize() {
-  ASSERT(!is_finalized() && position_ < buffer_.length());
+  ASSERT(!is_finalized() && position_ <= buffer_.length());
+  // If there is no space for null termination, overwrite last character.
+  if (position_ == buffer_.length()) {
+    position_--;
+    // Print ellipsis.
+    for (int i = 3; i > 0 && position_ > i; --i) buffer_[position_ - i] = '.';
+  }
   buffer_[position_] = '\0';
   // Make sure nobody managed to add a 0-character to the
   // buffer while building the string.

src/v8utils.cc

@@ -264,7 +264,7 @@ void StringBuilder::AddFormatted(const char* format, ...) {
 
 
 void StringBuilder::AddFormattedList(const char* format, va_list list) {
-  ASSERT(!is_finalized() && position_ < buffer_.length());
+  ASSERT(!is_finalized() && position_ <= buffer_.length());
   int n = OS::VSNPrintF(buffer_ + position_, format, list);
   if (n < 0 || n >= (buffer_.length() - position_)) {
     position_ = buffer_.length();

test/mjsunit/regress/regress-2624.js

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --print-code
+
+var source = '"snowmen invasion " + "';
+for(var i = 0; i < 800; i++) {
+  source += '\u2603';
+}
+source += '"';
+eval(source);
+