From d7198dfb950ad4b2b1c65ff1b22026782d231f3c Mon Sep 17 00:00:00 2001
From: Erik Johnston <erikj@element.io>
Date: Wed, 29 May 2024 11:52:48 +0100
Subject: [PATCH] Ignore attempts to send to-device messages to bad users
(#17240)
Currently sending a to-device message to a user ID with a dodgy
destination is accepted, but then ends up spamming the logs when we try
and send to the destination.
An alternative would be to reject the request, but I'm slightly nervous
that could break things.
---
changelog.d/17240.bugfix | 1 +
synapse/handlers/devicemessage.py | 7 +++++++
2 files changed, 8 insertions(+)
create mode 100644 changelog.d/17240.bugfix
diff --git a/changelog.d/17240.bugfix b/changelog.d/17240.bugfix
new file mode 100644
index 0000000000..c596d270ce
--- /dev/null
+++ b/changelog.d/17240.bugfix
@@ -0,0 +1 @@
+Ignore attempts to send to-device messages to bad users, to avoid log spam when we try to connect to the bad server.
diff --git a/synapse/handlers/devicemessage.py b/synapse/handlers/devicemessage.py
index 79be7c97c8..e56bdb4072 100644
--- a/synapse/handlers/devicemessage.py
+++ b/synapse/handlers/devicemessage.py
@@ -236,6 +236,13 @@ class DeviceMessageHandler:
local_messages = {}
remote_messages: Dict[str, Dict[str, Dict[str, JsonDict]]] = {}
for user_id, by_device in messages.items():
+ if not UserID.is_valid(user_id):
+ logger.warning(
+ "Ignoring attempt to send device message to invalid user: %r",
+ user_id,
+ )
+ continue
+
# add an opentracing log entry for each message
for device_id, message_content in by_device.items():
log_kv(
--
GitLab