Merge branch 'master' into develop

5 files changed, 98 insertions, 16 deletions

diff --git a/CHANGES.md b/CHANGES.md
index d6567e24d2..361fd1fc6c 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,14 @@
+Synapse 1.7.3 (2019-12-31)
+==========================
+
+This release fixes a long-standing bug in the state resolution algorithm.
+
+Bugfixes
+--------
+
+- Fix exceptions caused by state resolution choking on malformed events. ([\#6608](https://github.com/matrix-org/synapse/issues/6608))
+
+
 Synapse 1.7.2 (2019-12-20)
 ==========================
 
diff --git a/debian/changelog b/debian/changelog
index 2492b5db92..31791c127c 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.7.3) stable; urgency=medium
+
+  * New synapse release 1.7.3.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 31 Dec 2019 10:45:04 +0000
+
 matrix-synapse-py3 (1.7.2) stable; urgency=medium
 
   * New synapse release 1.7.2.
diff --git a/docs/sample_log_config.yaml b/docs/sample_log_config.yaml
new file mode 100644
index 0000000000..11e8f35f41
--- /dev/null
+++ b/docs/sample_log_config.yaml
@@ -0,0 +1,43 @@
+# Example log config file for synapse.
+#
+# This is a YAML file containing a standard Python logging configuration
+# dictionary. See [1] for details on the valid settings.
+#
+# [1]: https://docs.python.org/3.7/library/logging.config.html#configuration-dictionary-schema
+
+version: 1
+
+formatters:
+    precise:
+        format: '%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s - %(message)s'
+
+filters:
+    context:
+        (): synapse.logging.context.LoggingContextFilter
+        request: ""
+
+handlers:
+    file:
+        class: logging.handlers.RotatingFileHandler
+        formatter: precise
+        filename: /home/rav/work/synapse/homeserver.log
+        maxBytes: 104857600
+        backupCount: 10
+        filters: [context]
+        encoding: utf8
+    console:
+        class: logging.StreamHandler
+        formatter: precise
+        filters: [context]
+
+loggers:
+    synapse.storage.SQL:
+        # beware: increasing this to DEBUG will make synapse log sensitive
+        # information such as access tokens.
+        level: INFO
+
+root:
+    level: INFO
+    handlers: [file, console]
+
+disable_existing_loggers: false
diff --git a/synapse/__init__.py b/synapse/__init__.py
index 996101cf09..71cb611820 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -36,7 +36,7 @@ try:
 except ImportError:
     pass
 
-__version__ = "1.7.2"
+__version__ = "1.7.3"
 
 if bool(os.environ.get("SYNAPSE_TEST_PATCH_LOG_CONTEXTS", False)):
     # We import here so that we don't have to install a bunch of deps when
diff --git a/synapse/state/v2.py b/synapse/state/v2.py
index cb77ed5b78..72fb8a6317 100644
--- a/synapse/state/v2.py
+++ b/synapse/state/v2.py
@@ -183,16 +183,20 @@ def _get_power_level_for_sender(room_id, event_id, event_map, state_res_store):
 
     pl = None
     for aid in event.auth_event_ids():
-        aev = yield _get_event(room_id, aid, event_map, state_res_store)
-        if (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""):
+        aev = yield _get_event(
+            room_id, aid, event_map, state_res_store, allow_none=True
+        )
+        if aev and (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""):
             pl = aev
             break
 
     if pl is None:
         # Couldn't find power level. Check if they're the creator of the room
         for aid in event.auth_event_ids():
-            aev = yield _get_event(room_id, aid, event_map, state_res_store)
-            if (aev.type, aev.state_key) == (EventTypes.Create, ""):
+            aev = yield _get_event(
+                room_id, aid, event_map, state_res_store, allow_none=True
+            )
+            if aev and (aev.type, aev.state_key) == (EventTypes.Create, ""):
                 if aev.content.get("creator") == event.sender:
                     return 100
                 break
@@ -403,10 +407,17 @@ def _iterative_auth_checks(
 
         auth_events = {}
         for aid in event.auth_event_ids():
-            ev = yield _get_event(room_id, aid, event_map, state_res_store)
+            ev = yield _get_event(
+                room_id, aid, event_map, state_res_store, allow_none=True
+            )
 
-            if ev.rejected_reason is None:
-                auth_events[(ev.type, ev.state_key)] = ev
+            if not ev:
+                logger.warning(
+                    "auth_event id %s for event %s is missing", aid, event_id
+                )
+            else:
+                if ev.rejected_reason is None:
+                    auth_events[(ev.type, ev.state_key)] = ev
 
         for key in event_auth.auth_types_for_event(event):
             if key in resolved_state:
@@ -457,8 +468,10 @@ def _mainline_sort(
         auth_events = pl_ev.auth_event_ids()
         pl = None
         for aid in auth_events:
-            ev = yield _get_event(room_id, aid, event_map, state_res_store)
-            if (ev.type, ev.state_key) == (EventTypes.PowerLevels, ""):
+            ev = yield _get_event(
+                room_id, aid, event_map, state_res_store, allow_none=True
+            )
+            if ev and (ev.type, ev.state_key) == (EventTypes.PowerLevels, ""):
                 pl = aid
                 break
 
@@ -506,8 +519,10 @@ def _get_mainline_depth_for_event(event, mainline_map, event_map, state_res_stor
         event = None
 
         for aid in auth_events:
-            aev = yield _get_event(room_id, aid, event_map, state_res_store)
-            if (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""):
+            aev = yield _get_event(
+                room_id, aid, event_map, state_res_store, allow_none=True
+            )
+            if aev and (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""):
                 event = aev
                 break
 
@@ -516,7 +531,7 @@ def _get_mainline_depth_for_event(event, mainline_map, event_map, state_res_stor
 
 
 @defer.inlineCallbacks
-def _get_event(room_id, event_id, event_map, state_res_store):
+def _get_event(room_id, event_id, event_map, state_res_store, allow_none=False):
     """Helper function to look up event in event_map, falling back to looking
     it up in the store
 
@@ -525,15 +540,22 @@ def _get_event(room_id, event_id, event_map, state_res_store):
         event_id (str)
         event_map (dict[str,FrozenEvent])
         state_res_store (StateResolutionStore)
+        allow_none (bool): if the event is not found, return None rather than raising
+            an exception
 
     Returns:
-        Deferred[FrozenEvent]
+        Deferred[Optional[FrozenEvent]]
     """
     if event_id not in event_map:
         events = yield state_res_store.get_events([event_id], allow_rejected=True)
         event_map.update(events)
-    event = event_map[event_id]
-    assert event is not None
+    event = event_map.get(event_id)
+
+    if event is None:
+        if allow_none:
+            return None
+        raise Exception("Unknown event %s" % (event_id,))
+
     if event.room_id != room_id:
         raise Exception(
             "In state res for room %s, event %s is in %s"