From b4baf102bc6ee641f7f1946174f432feaf3f0836 Mon Sep 17 00:00:00 2001
From: Danil Chapovalov <danilchap@webrtc.org>
Date: Fri, 15 May 2020 16:49:37 +0200
Subject: [PATCH] in DependencyDescriptor writer do not leave remaing bits
 uninitialized

Bug: b/156462854
Change-Id: Iaceadb9cebdf5c4a34ff794966535cc873a53399
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/175109
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Erik Varga <erikvarga@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31282}
---
 modules/rtp_rtcp/source/rtp_dependency_descriptor_writer.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/modules/rtp_rtcp/source/rtp_dependency_descriptor_writer.cc b/modules/rtp_rtcp/source/rtp_dependency_descriptor_writer.cc
index 9e1a425666..d933a94128 100644
--- a/modules/rtp_rtcp/source/rtp_dependency_descriptor_writer.cc
+++ b/modules/rtp_rtcp/source/rtp_dependency_descriptor_writer.cc
@@ -74,6 +74,11 @@ bool RtpDependencyDescriptorWriter::Write() {
     WriteExtendedFields();
     WriteFrameDependencyDefinition();
   }
+  size_t remaining_bits = bit_writer_.RemainingBitCount();
+  if (remaining_bits > 0) {
+    // Zero remaining memory to avoid leaving it uninitialized.
+    WriteBits(/*val=*/0, remaining_bits);
+  }
   return !build_failed_;
 }