netdev - [PATCH v2] sctp: fix missing send up SCTP_SENDER_DRY

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Sun, 03 Jul 2011 03:28:04 +0800
From:	Wei Yongjun <weiyj.lk@...il.com>
To:	David Miller <davem@...emloft.net>
CC:	netdev@...r.kernel.org, linux-sctp@...r.kernel.org,
	Michael Tüxen 
	<Michael.Tuexen@...chi.franken.de>,
	Robin Seggelmann <seggelmann@...muenster.de>
Subject: [PATCH  v2] sctp: fix missing send up SCTP_SENDER_DRY_EVENT when
 subscribe it

From: Wei Yongjun <yjwei@...fujitsu.com>

We forgot to send up SCTP_SENDER_DRY_EVENT notification when
user app subscribes to this event, and there is no data to be
sent or retransmit.

This is required by the Socket API and used by the DTLS/SCTP
implementation.

Reported-by: Michael Tüxen <Michael.Tuexen@...chi.franken.de>
Signed-off-by: Wei Yongjun <yjwei@...fujitsu.com>
Tested-by: Robin Seggelmann <seggelmann@...muenster.de>

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 6766913..99e25de 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -2073,10 +2073,33 @@ static int sctp_setsockopt_disable_fragments(struct sock *sk,
 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
 				  unsigned int optlen)
 {
+	struct sctp_association *asoc;
+	struct sctp_ulpevent *event;
+
 	if (optlen > sizeof(struct sctp_event_subscribe))
 		return -EINVAL;
 	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
 		return -EFAULT;
+
+	/* 
+	 * At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
+	 * if there is no data to be sent or retransmit, the stack will
+	 * immediately send up this notification.
+	 */
+	if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
+				       &sctp_sk(sk)->subscribe)) {
+		asoc = sctp_id2assoc(sk, 0);
+
+		if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
+			event = sctp_ulpevent_make_sender_dry_event(asoc,
+					GFP_ATOMIC);
+			if (!event)
+				return -ENOMEM;
+
+			sctp_ulpq_tail_event(&asoc->ulpq, event);
+		}
+	}
+
 	return 0;
 }
 
-- 
1.7.5.1


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html