Bug 1554411 - Make sure to deregister each HTTP/2 tunnel with the same key as used for its registration, r=dragana

Differential Revision: https://phabricator.services.mozilla.com/D40406

--HG--
extra : moz-landing-system : lando

netwerk/protocol/http/Http2Session.cpp

@@ -4149,33 +4149,36 @@ void Http2Session::ConnectSlowConsumer(Http2Stream* stream) {
 }
 
 uint32_t Http2Session::FindTunnelCount(nsHttpConnectionInfo* aConnInfo) {
+  return FindTunnelCount(aConnInfo->HashKey());
+}
+uint32_t Http2Session::FindTunnelCount(nsCString const& aHashKey) {
   MOZ_ASSERT(OnSocketThread(), "not on socket thread");
   uint32_t rv = 0;
-  mTunnelHash.Get(aConnInfo->HashKey(), &rv);
+  mTunnelHash.Get(aHashKey, &rv);
   return rv;
 }
 
 void Http2Session::RegisterTunnel(Http2Stream* aTunnel) {
   MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-  nsHttpConnectionInfo* ci = aTunnel->Transaction()->ConnectionInfo();
-  uint32_t newcount = FindTunnelCount(ci) + 1;
-  mTunnelHash.Remove(ci->HashKey());
-  mTunnelHash.Put(ci->HashKey(), newcount);
+  nsCString const& regKey = aTunnel->RegistrationKey();
+  uint32_t newcount = FindTunnelCount(regKey) + 1;
+  mTunnelHash.Remove(regKey);
+  mTunnelHash.Put(regKey, newcount);
   LOG3(("Http2Stream::RegisterTunnel %p stream=%p tunnels=%d [%s]", this,
-        aTunnel, newcount, ci->HashKey().get()));
+        aTunnel, newcount, regKey.get()));
 }
 
 void Http2Session::UnRegisterTunnel(Http2Stream* aTunnel) {
   MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-  nsHttpConnectionInfo* ci = aTunnel->Transaction()->ConnectionInfo();
-  MOZ_ASSERT(FindTunnelCount(ci));
-  uint32_t newcount = FindTunnelCount(ci) - 1;
-  mTunnelHash.Remove(ci->HashKey());
+  nsCString const& regKey = aTunnel->RegistrationKey();
+  MOZ_ASSERT(FindTunnelCount(regKey));
+  uint32_t newcount = FindTunnelCount(regKey) - 1;
+  mTunnelHash.Remove(regKey);
   if (newcount) {
-    mTunnelHash.Put(ci->HashKey(), newcount);
+    mTunnelHash.Put(regKey, newcount);
   }
   LOG3(("Http2Session::UnRegisterTunnel %p stream=%p tunnels=%d [%s]", this,
-        aTunnel, newcount, ci->HashKey().get()));
+        aTunnel, newcount, regKey.get()));
 }
 
 void Http2Session::CreateTunnel(nsHttpTransaction* trans,

netwerk/protocol/http/Http2Session.h

@@ -596,6 +596,7 @@ class Http2Session final : public ASpdySession,
   void RegisterTunnel(Http2Stream*);
   void UnRegisterTunnel(Http2Stream*);
   uint32_t FindTunnelCount(nsHttpConnectionInfo*);
+  uint32_t FindTunnelCount(nsCString const&);
   nsDataHashtable<nsCStringHashKey, uint32_t> mTunnelHash;
   uint32_t mTrrStreams;
 

netwerk/protocol/http/Http2Stream.cpp

@@ -1592,6 +1592,17 @@ nsresult Http2Stream::OnWriteSegment(char* buf, uint32_t count,
 
 /// connect tunnels
 
+nsCString& Http2Stream::RegistrationKey() {
+  if (mRegistrationKey.IsEmpty()) {
+    MOZ_ASSERT(Transaction());
+    MOZ_ASSERT(Transaction()->ConnectionInfo());
+
+    mRegistrationKey = Transaction()->ConnectionInfo()->HashKey();
+  }
+
+  return mRegistrationKey;
+}
+
 void Http2Stream::ClearTransactionsBlockedOnTunnel() {
   MOZ_ASSERT(OnSocketThread(), "not on socket thread");
 

netwerk/protocol/http/Http2Stream.h

@@ -365,6 +365,11 @@ class Http2Stream : public nsAHttpSegmentReader,
   /// connect tunnels
  public:
   bool IsTunnel() { return mIsTunnel; }
+  // TODO - remove as part of bug 1564120 fix?
+  // This method saves the key the tunnel was registered under, so that when the
+  // associated transaction connection info hash key changes, we still find it
+  // and decrement the correct item in the session's tunnel hash table.
+  nsCString& RegistrationKey();
 
  private:
   void ClearTransactionsBlockedOnTunnel();
@@ -373,6 +378,7 @@ class Http2Stream : public nsAHttpSegmentReader,
 
   bool mIsTunnel;
   bool mPlainTextTunnel;
+  nsCString mRegistrationKey;
 
   /// websockets
  public: