From c850dd9a8e4e4f78fbe0b44686f3824b901236f6 Mon Sep 17 00:00:00 2001 From: Erik Johnston Date: Fri, 23 Oct 2020 17:12:59 +0100 Subject: Fix handling of User-Agent headers with bad utf-8. (#8632) --- synapse/http/site.py | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'synapse/http') diff --git a/synapse/http/site.py b/synapse/http/site.py index 6e79b47828..ca673028e4 100644 --- a/synapse/http/site.py +++ b/synapse/http/site.py @@ -109,8 +109,14 @@ class SynapseRequest(Request): method = self.method.decode("ascii") return method - def get_user_agent(self): - return self.requestHeaders.getRawHeaders(b"User-Agent", [None])[-1] + def get_user_agent(self, default: str) -> str: + """Return the last User-Agent header, or the given default. + """ + user_agent = self.requestHeaders.getRawHeaders(b"User-Agent", [None])[-1] + if user_agent is None: + return default + + return user_agent.decode("ascii", "replace") def render(self, resrc): # this is called once a Resource has been found to serve the request; in our @@ -274,11 +280,7 @@ class SynapseRequest(Request): # with maximum recursion trying to log errors about # the charset problem. # c.f. https://github.com/matrix-org/synapse/issues/3471 - user_agent = self.get_user_agent() - if user_agent is not None: - user_agent = user_agent.decode("utf-8", "replace") - else: - user_agent = "-" + user_agent = self.get_user_agent("-") code = str(self.code) if not self.finished: -- cgit 1.5.1