From: Stephan Bosch <stephan.bosch@dovecot.fi>
Date: Wed, 26 Sep 2018 10:25:59 +0000 (+0200)
Subject: lib-smtp: client: Make the initialization of the connection after SSL handshake reliable.
X-Git-Tag: 2.3.4~171
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c4f8ab0368c5dc5cfe3a7f018761c31c0033ab7f;p=thirdparty%2Fdovecot%2Fcore.git

lib-smtp: client: Make the initialization of the connection after SSL handshake reliable.

Before, the connection was not guaranteed to be fully initialized after the SSL
handshake. The problem would occur when the handshake finished while writing the
SSL output stream. In a similar HTTP client issue, this caused a segfault.
---

diff --git a/src/lib-smtp/smtp-client-connection.c b/src/lib-smtp/smtp-client-connection.c
index bbb67e2a1a..3b5e0af28e 100644
--- a/src/lib-smtp/smtp-client-connection.c
+++ b/src/lib-smtp/smtp-client-connection.c
@@ -1003,8 +1003,10 @@ static void smtp_client_connection_input(struct connection *_conn)
 			i_assert(ret == 0);
 			return;
 		}
+	}
 
-		/* ready for SMTP handshake */
+	if (!conn->connect_succeeded) {
+		/* just got ready for SMTP handshake */
 		smtp_client_connection_established(conn);
 	}
 
@@ -1137,6 +1139,9 @@ static void smtp_client_connection_destroy(struct connection *_conn)
 static void
 smtp_client_connection_established(struct smtp_client_connection *conn)
 {
+	i_assert(!conn->connect_succeeded);
+	conn->connect_succeeded = TRUE;
+
 	if (conn->to_connect != NULL)
 		timeout_reset(conn->to_connect);
 
diff --git a/src/lib-smtp/smtp-client-private.h b/src/lib-smtp/smtp-client-private.h
index f70b2fd684..b0cbb5eeeb 100644
--- a/src/lib-smtp/smtp-client-private.h
+++ b/src/lib-smtp/smtp-client-private.h
@@ -163,6 +163,7 @@ struct smtp_client_connection {
 	bool authenticated:1;
 	bool initial_xclient_sent:1;
 	bool connect_failed:1;
+	bool connect_succeeded:1;
 	bool handshake_failed:1;
 	bool corked:1;
 	bool sent_quit:1;