Fix null-pointer dereference in RTPSenderVideo.

webrtc/modules/rtp_rtcp/source/rtp_sender_video.cc

 /*
  *  Copyright (c) 2012 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 212 matching lines @@
 }
 
 int32_t RTPSenderVideo::SendVideo(const RtpVideoCodecTypes videoType,
                                   const FrameType frameType,
                                   const int8_t payloadType,
                                   const uint32_t captureTimeStamp,
                                   int64_t capture_time_ms,
                                   const uint8_t* payloadData,
                                   const size_t payloadSize,
                                   const RTPFragmentationHeader* fragmentation,
-                                  const RTPVideoHeader* rtpHdr) {
+                                  const RTPVideoHeader* video_header) {
   if (payloadSize == 0) {
     return -1;
   }
 
-  rtc::scoped_ptr<RtpPacketizer> packetizer(
-      RtpPacketizer::Create(videoType, _rtpSender.MaxDataPayloadLength(),
-                            &(rtpHdr->codecHeader), frameType));
+  rtc::scoped_ptr<RtpPacketizer> packetizer(RtpPacketizer::Create(
+      videoType, _rtpSender.MaxDataPayloadLength(),
+      video_header ? &(video_header->codecHeader) : nullptr, frameType));
 
   StorageType storage;
   bool fec_enabled;
   {
     CriticalSectionScoped cs(crit_.get());
     FecProtectionParams* fec_params =
         frameType == kVideoFrameKey ? &key_fec_params_ : &delta_fec_params_;
     producer_fec_.SetFecParameters(fec_params, 0);
     storage = packetizer->GetStorageType(_retransmissionSettings);
     fec_enabled = fec_enabled_;
   }
 
   // Register CVO rtp header extension at the first time when we receive a frame
   // with pending rotation.
   RTPSenderInterface::CVOMode cvo_mode = RTPSenderInterface::kCVONone;
-  if (rtpHdr && rtpHdr->rotation != kVideoRotation_0) {
+  if (video_header && video_header->rotation != kVideoRotation_0) {
     cvo_mode = _rtpSender.ActivateCVORtpHeaderExtension();
   }
 
   uint16_t rtp_header_length = _rtpSender.RTPHeaderLength();
   size_t payload_bytes_to_send = payloadSize;
   const uint8_t* data = payloadData;
 
   // TODO(changbin): we currently don't support to configure the codec to
   // output multiple partitions for VP8. Should remove below check after the
   // issue is fixed.
@@ skipping 18 matching lines @@
     // http://www.etsi.org/deliver/etsi_ts/126100_126199/126114/12.07.00_60/
     // ts_126114v120700p.pdf Section 7.4.5:
     // The MTSI client shall add the payload bytes as defined in this clause
     // onto the last RTP packet in each group of packets which make up a key
     // frame (I-frame or IDR frame in H.264 (AVC), or an IRAP picture in H.265
     // (HEVC)). The MTSI client may also add the payload bytes onto the last RTP
     // packet in each group of packets which make up another type of frame
     // (e.g. a P-Frame) only if the current value is different from the previous
     // value sent.
     // Here we are adding it to every packet of every frame at this point.
-    if (!rtpHdr) {
+    if (!video_header) {
       RTC_DCHECK(!_rtpSender.IsRtpHeaderExtensionRegistered(
           kRtpExtensionVideoRotation));
     } else if (cvo_mode == RTPSenderInterface::kCVOActivated) {
       // Checking whether CVO header extension is registered will require taking
       // a lock. It'll be a no-op if it's not registered.
       // TODO(guoweis): For now, all packets sent will carry the CVO such that
       // the RTP header length is consistent, although the receiver side will
       // only exam the packets with marker bit set.
       size_t packetSize = payloadSize + rtp_header_length;
       RtpUtility::RtpHeaderParser rtp_parser(dataBuffer, packetSize);
       RTPHeader rtp_header;
       rtp_parser.Parse(&rtp_header);
       _rtpSender.UpdateVideoRotation(dataBuffer, packetSize, rtp_header,
-                                     rtpHdr->rotation);
+                                     video_header->rotation);
     }
     if (fec_enabled) {
       SendVideoPacketAsRed(dataBuffer, payload_bytes_in_packet,
                            rtp_header_length, _rtpSender.SequenceNumber(),
                            captureTimeStamp, capture_time_ms, storage,
                            packetizer->GetProtectionType() == kProtectedPacket);
     } else {
       SendVideoPacket(dataBuffer, payload_bytes_in_packet, rtp_header_length,
                       _rtpSender.SequenceNumber(), captureTimeStamp,
                       capture_time_ms, storage);
@@ skipping 30 matching lines @@
   CriticalSectionScoped cs(crit_.get());
   return _retransmissionSettings;
 }
 
 void RTPSenderVideo::SetSelectiveRetransmissions(uint8_t settings) {
   CriticalSectionScoped cs(crit_.get());
   _retransmissionSettings = settings;
 }
 
 }  // namespace webrtc