From 967d2ab9df89570da856e61dc0d92455e33428e9 Mon Sep 17 00:00:00 2001
From: Till Faelligen <2353100+S7evinK@users.noreply.github.com>
Date: Fri, 7 Oct 2022 15:07:18 +0200
Subject: [PATCH] Comments, guard against marshaling nil values

---
 federationapi/internal/perform.go           | 10 ++++++----
 roomserver/internal/perform/perform_join.go |  2 +-
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/federationapi/internal/perform.go b/federationapi/internal/perform.go
index ae200f617..28ec48d7b 100644
--- a/federationapi/internal/perform.go
+++ b/federationapi/internal/perform.go
@@ -270,10 +270,12 @@ func (r *FederationInternalAPI) performJoinUsingServer(
 	// If we successfully performed a send_join above then the other
 	// server now thinks we're a part of the room. Send the newly
 	// returned state to the roomserver to update our local view.
-	event, err = event.SetUnsigned(unsigned)
-	if err != nil {
-		// non-fatal, log and continue
-		logrus.WithError(err).Errorf("Failed to set prev content")
+	if unsigned != nil {
+		event, err = event.SetUnsigned(unsigned)
+		if err != nil {
+			// non-fatal, log and continue
+			logrus.WithError(err).Errorf("Failed to set unsigned content")
+		}
 	}
 
 	if err = roomserverAPI.SendEventWithState(
diff --git a/roomserver/internal/perform/perform_join.go b/roomserver/internal/perform/perform_join.go
index 10b01d623..262273ff5 100644
--- a/roomserver/internal/perform/perform_join.go
+++ b/roomserver/internal/perform/perform_join.go
@@ -361,7 +361,7 @@ func (r *Joiner) performFederatedJoinRoomByID(
 		UserID:      req.UserID,        // the user ID joining the room
 		ServerNames: req.ServerNames,   // the server to try joining with
 		Content:     req.Content,       // the membership event content
-		Unsigned:    req.Unsigned,
+		Unsigned:    req.Unsigned,      // the unsigned event content, if any
 	}
 	fedRes := fsAPI.PerformJoinResponse{}
 	r.FSAPI.PerformJoin(ctx, &fedReq, &fedRes)