commit e70028e43fded41310d41cc93b90f2e689c04725
author Joachim Bauch <jbauch@webrtc.org> Fri May 29 01:20:52 2015 +0200
committer Joachim Bauch <jbauch@webrtc.org> Thu May 28 23:21:00 2015 +0000
tree a45620379dcd38dc5c8dba0d329a9047bd64605d
parent 9e3cb336d4c62d4632552293eddd59612829ece1

Protect access to shared list of SRTP sessions.

This is a follow up to https://webrtc-codereview.appspot.com/47319004/
and locks access to the static list of SRTP sessions to prevent potential
race conditions.

BUG=4042
R=juberti@google.com

Review URL: https://webrtc-codereview.appspot.com/52609004

Cr-Commit-Position: refs/heads/master@{#9326}

talk/session/media/srtpfilter.cc

diff --git a/talk/session/media/srtpfilter.cc b/talk/session/media/srtpfilter.cc
index 5fc6946..33e42c0 100644
--- a/talk/session/media/srtpfilter.cc
+++ b/talk/session/media/srtpfilter.cc
@@ -474,6 +474,8 @@
 #ifdef HAVE_SRTP
 
 bool SrtpSession::inited_ = false;
+
+// This lock protects SrtpSession::inited_ and SrtpSession::sessions_.
 rtc::GlobalLockPod SrtpSession::lock_;
 
 SrtpSession::SrtpSession()
@@ -482,12 +484,18 @@
       rtcp_auth_tag_len_(0),
       srtp_stat_(new SrtpStat()),
       last_send_seq_num_(-1) {
-  sessions()->push_back(this);
+  {
+    rtc::GlobalLockScope ls(&lock_);
+    sessions()->push_back(this);
+  }
   SignalSrtpError.repeat(srtp_stat_->SignalSrtpError);
 }
 
 SrtpSession::~SrtpSession() {
-  sessions()->erase(std::find(sessions()->begin(), sessions()->end(), this));
+  {
+    rtc::GlobalLockScope ls(&lock_);
+    sessions()->erase(std::find(sessions()->begin(), sessions()->end(), this));
+  }
   if (session_) {
     srtp_dealloc(session_);
   }
@@ -766,6 +774,8 @@
 }
 
 void SrtpSession::HandleEventThunk(srtp_event_data_t* ev) {
+  rtc::GlobalLockScope ls(&lock_);
+
   for (std::list<SrtpSession*>::iterator it = sessions()->begin();
        it != sessions()->end(); ++it) {
     if ((*it)->session_ == ev->session) {