Fix panic when OnReadCompleted receives negative bytesRead

Author: nekohasekai

bidirectional_conn.go

@@ -143,12 +143,16 @@ func (c *BidirectionalConn) Read(p []byte) (n int, err error) {
 
 	select {
 	case bytesRead := <-c.read:
+		if bytesRead < 0 {
+			return 0, net.ErrClosed
+		}
+		if bytesRead == 0 {
+			return 0, io.EOF
+		}
 		if bytesRead > len(p) {
 			bytesRead = len(p)
 		}
-		if bytesRead > 0 {
-			copy(p, readBuffer[:bytesRead])
-		}
+		copy(p, readBuffer[:bytesRead])
 		return bytesRead, nil
 	case <-c.done:
 		// Wait for Cronet to finish using the buffer before returning.
@@ -364,6 +368,15 @@ func (c *bidirectionalHandler) OnReadCompleted(stream BidirectionalStream, bytes
 		return
 	}
 
+	if bytesRead < 0 {
+		c.access.Unlock()
+		c.signalReadDone()
+		c.signalWriteDone()
+		c.cancelOnce.Do(func() {})
+		c.Close(net.ErrClosed)
+		return
+	}
+
 	if bytesRead == 0 {
 		c.access.Unlock()
 		c.signalReadDone()