Fix parsing padding byte in rtp header extension

webrtc/modules/rtp_rtcp/source/rtp_utility.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 300 matching lines @@
     // +-+-+-+-+-+-+-+-+
     // |  ID   |  len  |
     // +-+-+-+-+-+-+-+-+
 
     // Note that 'len' is the header extension element length, which is the
     // number of bytes - 1.
     const int id = (*ptr & 0xf0) >> 4;
     const int len = (*ptr & 0x0f);
     ptr++;
 
+    if (id == 0) {
+      // Padding byte, skip ignoring len.
+      continue;
+    }
+
     if (id == 15) {
-      LOG(LS_WARNING)
+      LOG(LS_VERBOSE)
           << "RTP extension header 15 encountered. Terminate parsing.";
       return;
     }
 
     if (ptrRTPDataExtensionEnd - ptr < (len + 1)) {
       LOG(LS_WARNING) << "Incorrect one-byte extension len: " << (len + 1)
                       << ", bytes left in buffer: "
                       << (ptrRTPDataExtensionEnd - ptr);
       return;
     }
@@ skipping 106 matching lines @@
               max_playout_delay * kPlayoutDelayGranularityMs;
           break;
         }
         default: {
           LOG(LS_WARNING) << "Extension type not implemented: " << type;
           return;
         }
       }
     }
     ptr += (len + 1);
-    uint8_t num_bytes = ParsePaddingBytes(ptrRTPDataExtensionEnd, ptr);
-    ptr += num_bytes;
   }
 }
 
-uint8_t RtpHeaderParser::ParsePaddingBytes(
-    const uint8_t* ptrRTPDataExtensionEnd,
-    const uint8_t* ptr) const {
-  uint8_t num_zero_bytes = 0;
-  while (ptrRTPDataExtensionEnd - ptr > 0) {
-    if (*ptr != 0) {
-      return num_zero_bytes;
-    }
-    ptr++;
-    num_zero_bytes++;
-  }
-  return num_zero_bytes;
-}
 }  // namespace RtpUtility
 }  // namespace webrtc