From edc244eec429d587eee28e336e0baae9f9de0e0a Mon Sep 17 00:00:00 2001
From: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>
Date: Wed, 15 Jan 2020 18:05:18 +0000
Subject: [PATCH] Remove duplicate session check in web fallback servlet
 (#6702)

---
 changelog.d/6702.misc                | 1 +
 synapse/rest/client/v2_alpha/auth.py | 4 ----
 2 files changed, 1 insertion(+), 4 deletions(-)
 create mode 100644 changelog.d/6702.misc

diff --git a/changelog.d/6702.misc b/changelog.d/6702.misc
new file mode 100644
index 0000000000..f7bc98409c
--- /dev/null
+++ b/changelog.d/6702.misc
@@ -0,0 +1 @@
+Remove duplicate check for the `session` query parameter on the `/auth/xxx/fallback/web` Client-Server endpoint.
\ No newline at end of file
diff --git a/synapse/rest/client/v2_alpha/auth.py b/synapse/rest/client/v2_alpha/auth.py
index 7a256b6ecb..50e080673b 100644
--- a/synapse/rest/client/v2_alpha/auth.py
+++ b/synapse/rest/client/v2_alpha/auth.py
@@ -206,10 +206,6 @@ class AuthRestServlet(RestServlet):
 
             return None
         elif stagetype == LoginType.TERMS:
-            if ("session" not in request.args or len(request.args["session"])) == 0:
-                raise SynapseError(400, "No session supplied")
-
-            session = request.args["session"][0]
             authdict = {"session": session}
 
             success = await self.auth_handler.add_oob_auth(