diff --git a/changelog.d/15348.misc b/changelog.d/15348.misc
new file mode 100644
index 0000000000..f9bfc581ad
--- /dev/null
+++ b/changelog.d/15348.misc
@@ -0,0 +1 @@
+Prune user's old devices on login if they have too many.
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index bb1df1e60f..7e9d065f50 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -946,6 +946,8 @@ class RegistrationHandler:
if not device_ids:
return
+ logger.info("Pruning %d stale devices for %s", len(device_ids), user_id)
+
# Now spawn a background loop that deletes said devices.
async def _prune_too_many_devices_loop() -> None:
if user_id in self._currently_pruning_devices_for_users:
diff --git a/synapse/storage/databases/main/devices.py b/synapse/storage/databases/main/devices.py
index 7647cda2c6..f61b7bc96e 100644
--- a/synapse/storage/databases/main/devices.py
+++ b/synapse/storage/databases/main/devices.py
@@ -1638,19 +1638,22 @@ class DeviceBackgroundUpdateStore(SQLBaseStore):
"""
rows = await self.db_pool.execute(
- "check_too_many_devices_for_user_last_seen", None, sql, (user_id,)
+ "check_too_many_devices_for_user_last_seen",
+ None,
+ sql,
+ user_id,
)
if rows:
max_last_seen = max(rows[0][0], max_last_seen)
# Fetch the devices to delete.
sql = """
- SELECT DISTINCT device_id FROM devices
+ SELECT device_id FROM devices
LEFT JOIN e2e_device_keys_json USING (user_id, device_id)
WHERE
user_id = ?
AND NOT hidden
- AND last_seen < ?
+ AND last_seen <= ?
AND key_json IS NULL
ORDER BY last_seen
"""
diff --git a/tests/rest/client/test_register.py b/tests/rest/client/test_register.py
index b228dba861..7ae84e3139 100644
--- a/tests/rest/client/test_register.py
+++ b/tests/rest/client/test_register.py
@@ -794,6 +794,53 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
ApprovalNoticeMedium.NONE, channel.json_body["approval_notice_medium"]
)
+ def test_check_stale_devices_get_pruned(self) -> None:
+ """Check that if a user has some stale devices we log them out when they
+ log in a new device."""
+
+ # Register some devices, but not too many that we go over the threshold
+ # where we prune more aggressively.
+ user_id = self.register_user("user", "pass")
+ for _ in range(0, 50):
+ self.login(user_id, "pass")
+
+ store = self.hs.get_datastores().main
+
+ res = self.get_success(store.get_devices_by_user(user_id))
+ self.assertEqual(len(res), 50)
+
+ # Advance time so that the above devices are considered "old".
+ self.reactor.advance(30 * 24 * 60 * 60 * 1000)
+
+ self.login(user_id, "pass")
+
+ self.reactor.pump([60] * 10) # Ensure background job runs
+
+ # We expect all old devices to have been logged out
+ res = self.get_success(store.get_devices_by_user(user_id))
+ self.assertEqual(len(res), 1)
+
+ def test_check_recent_devices_get_pruned(self) -> None:
+ """Check that if a user has many devices we log out the last oldest
+ ones.
+
+ Note: this is similar to above, except if we lots of devices we prune
+ devices even if they're not old.
+ """
+
+ # Register a lot of devices in a short amount of time
+ user_id = self.register_user("user", "pass")
+ for _ in range(0, 100):
+ self.login(user_id, "pass")
+ self.reactor.advance(100)
+
+ store = self.hs.get_datastores().main
+
+ # We keep up to 50 devices that have been used in the last week, plus
+ # the device that was last logged in.
+ res = self.get_success(store.get_devices_by_user(user_id))
+ self.assertEqual(len(res), 51)
+
class AccountValidityTestCase(unittest.HomeserverTestCase):
servlets = [
|
