Fix crash parsing malformed rtp packet

webrtc/modules/rtp_rtcp/source/rtp_packet.cc

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 398 matching lines @@
   payload_size_ = size - payload_offset_ - padding_size_;
   return true;
 }
 
 bool Packet::FindExtension(ExtensionType type,
                            uint8_t length,
                            uint16_t* offset) const {
   RTC_DCHECK(offset);
   for (size_t i = 0; i < num_extensions_; ++i) {
     if (extension_entries_[i].type == type) {
-      RTC_CHECK_EQ(length, extension_entries_[i].length)
-          << "Length mismatch for extension '" << type << "'"
-          << "should be " << length << ", received "
-          << extension_entries_[i].length;
+      if (length != extension_entries_[i].length) {
+        LOG(LS_WARNING) << "Length mismatch for extension '" << type
+                        << "': expected " << static_cast<int>(length)
+                        << ", received "
+                        << static_cast<int>(extension_entries_[i].length);
+        return false;
+      }
       *offset = extension_entries_[i].offset;
       return true;
     }
   }
   return false;
 }
 
 bool Packet::AllocateExtension(ExtensionType type,
                                uint8_t length,
                                uint16_t* offset) {
@@ skipping 67 matching lines @@
 uint8_t* Packet::WriteAt(size_t offset) {
   return buffer_.data() + offset;
 }
 
 void Packet::WriteAt(size_t offset, uint8_t byte) {
   buffer_.data()[offset] = byte;
 }
 
 }  // namespace rtp
 }  // namespace webrtc