From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Thu, 29 Oct 2020 10:55:21 +0000 (+0200)
Subject: imap: Fix potential hang if client disconnects with pipelined ambiguous commands
X-Git-Tag: 2.3.14.rc1~302
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6fad5cd6fc3cc2f3082960b31752907e4a82e7ac;p=thirdparty%2Fdovecot%2Fcore.git

imap: Fix potential hang if client disconnects with pipelined ambiguous commands

For example if client pipelines FETCH+LOGOUT commands and disconnects during
a large FETCH output, the LOGOUT command is processed as waiting for
unambiguity. This code path however doesn't detect a client disconnection,
and input IO handler is removed so it can't detect it either. So the imap
process hangs.
---

diff --git a/src/imap/imap-client.c b/src/imap/imap-client.c
index ca5db576b2..2c7681d6d6 100644
--- a/src/imap/imap-client.c
+++ b/src/imap/imap-client.c
@@ -1117,7 +1117,9 @@ void client_continue_pending_input(struct client *client)
 		if (!ret)
 			break;
 	}
-	if (!client->input->closed && !client->output->closed)
+	if (client->input->closed || client->output->closed)
+		client_destroy(client, NULL);
+	else
 		client_check_command_hangs(client);
 }