Don't allow the error_logger mailbox to grow unbounded when flooded with connection attempts.bug22340

1 files changed, 7 insertions, 0 deletions

diff --git a/src/tcp_acceptor.erl b/src/tcp_acceptor.erl
index 3b23daa5..cc4982c9 100644
--- a/src/tcp_acceptor.erl
+++ b/src/tcp_acceptor.erl
@@ -75,6 +75,13 @@ handle_info({inet_async, LSock, Ref, {ok, Sock}},
         error_logger:info_msg("accepted TCP connection on ~s:~p from ~s:~p~n",
                               [inet_parse:ntoa(Address), Port,
                                inet_parse:ntoa(PeerAddress), PeerPort]),
+        %% In the event that somebody floods us with connections we can spew
+        %% the above message at error_logger faster than it can keep up.
+        %% So error_logger's mailbox grows unbounded until we eat all the
+        %% memory available and crash. So here's a meaningless synchronous call
+        %% to the underlying gen_event mechanism - when it returns the mailbox
+        %% is drained.
+        gen_event:which_handlers(error_logger),
         %% handle
         file_handle_cache:release_on_death(apply(M, F, A ++ [Sock]))
     catch {inet_error, Reason} ->