fix: srtpWriteFuture would block in read if read after close

peerconnection.go

@@ -1515,11 +1515,15 @@ func (pc *PeerConnection) undeclaredMediaProcessor() {
 				return
 			}
 
-			_, ssrc, err := srtcpSession.AcceptStream()
+			s, ssrc, err := srtcpSession.AcceptStream()
 			if err != nil {
 				pc.log.Warnf("Failed to accept RTCP %v", err)
 				return
 			}
+			time.AfterFunc(5*time.Minute, func() {
+				s.Close()
+			})
+
 			pc.log.Warnf("Incoming unhandled RTCP ssrc(%d), OnTrack will not be fired", ssrc)
 		}
 	}()

rtpreceiver.go

@@ -335,9 +335,11 @@ func (r *RTPReceiver) Stop() error {
 			}
 			if fec := r.tracks[i].fecTrack; fec != nil {
 				errs = append(errs, closefunc(fec)...)
+				r.api.interceptor.UnbindRemoteStream(&fec.streamInfo)
 			}
 			if rtx := r.tracks[i].rtxTrack; rtx != nil {
 				errs = append(errs, closefunc(rtx)...)
+				r.api.interceptor.UnbindRemoteStream(&rtx.streamInfo)
 			}
 
 			err = util.FlattenErrs(errs)

srtp_writer_future.go

@@ -4,6 +4,7 @@ package webrtc
 
 import (
 	"io"
+	"sync"
 	"sync/atomic"
 	"time"
 
@@ -17,6 +18,8 @@ type srtpWriterFuture struct {
 	rtpSender      *RTPSender
 	rtcpReadStream atomic.Value // *srtp.ReadStreamSRTCP
 	rtpWriteStream atomic.Value // *srtp.WriteStreamSRTP
+	mu             sync.Mutex
+	closed         bool
 }
 
 func (s *srtpWriterFuture) init(returnWhenNoSRTP bool) error {
@@ -36,6 +39,12 @@ func (s *srtpWriterFuture) init(returnWhenNoSRTP bool) error {
 		}
 	}
 
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.closed {
+		return io.ErrClosedPipe
+	}
+
 	srtcpSession, err := s.rtpSender.transport.getSRTCPSession()
 	if err != nil {
 		return err
@@ -62,6 +71,13 @@ func (s *srtpWriterFuture) init(returnWhenNoSRTP bool) error {
 }
 
 func (s *srtpWriterFuture) Close() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.closed {
+		return nil
+	}
+
+	s.closed = true
 	if value := s.rtcpReadStream.Load(); value != nil {
 		return value.(*srtp.ReadStreamSRTCP).Close()
 	}