quic: fix data race caused by aliased DCID

The initServer function was retaining a reference to a []byte that aliases a packet buffer, which is subsequently recycled. Make a copy of the data before retaining it. Fixes golang/go#63783 Change-Id: I3dbb0cdfd78681014dec97ff9909ff6c7dbf82ba Reviewed-on: https://go-review.googlesource.com/c/net/+/538615 LUCI-TryBot-Result: Go LUCI <[email protected]> Auto-Submit: Damien Neil <[email protected]> Reviewed-by: Jonathan Amsterdam <[email protected]>
golang · Oct 30, 2023 · 0526b49 · 0526b49
1 parent 6d267b1
commit 0526b49
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/internal/quic/conn_id.go b/internal/quic/conn_id.go
@@ -97,12 +97,13 @@ func (s *connIDState) initClient(c *Conn) error {
 }
 
 func (s *connIDState) initServer(c *Conn, dstConnID []byte) error {
+	dstConnID = cloneBytes(dstConnID)
 	// Client-chosen, transient connection ID received in the first Initial packet.
 	// The server will not use this as the Source Connection ID of packets it sends,
 	// but remembers it because it may receive packets sent to this destination.
 	s.local = append(s.local, connID{
 		seq: -1,
-		cid: cloneBytes(dstConnID),
+		cid: dstConnID,
 	})
 
 	// Server chooses a connection ID, and sends it in the Source Connection ID of