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>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20171213015455.6455-51-alexander.levin@verizon.com>
Date:   Wed, 13 Dec 2017 01:55:24 +0000
From:   alexander.levin@...izon.com
To:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "stable@...r.kernel.org" <stable@...r.kernel.org>
Cc:     Mike Manning <mmanning@...cade.com>,
        "David S . Miller" <davem@...emloft.net>,
        alexander.levin@...izon.com
Subject: [PATCH AUTOSEL for 4.14 51/60] net: ipv6: send NS for DAD when link
 operationally up

From: Mike Manning <mmanning@...cade.com>

[ Upstream commit 1f372c7bfb23286d2bf4ce0423ab488e86b74bb2 ]

The NS for DAD are sent on admin up as long as a valid qdisc is found.
A race condition exists by which these packets will not egress the
interface if the operational state of the lower device is not yet up.
The solution is to delay DAD until the link is operationally up
according to RFC2863. Rather than only doing this, follow the existing
code checks by deferring IPv6 device initialization altogether. The fix
allows DAD on devices like tunnels that are controlled by userspace
control plane. The fix has no impact on regular deployments, but means
that there is no IPv6 connectivity until the port has been opened in
the case of port-based network access control, which should be
desirable.

Signed-off-by: Mike Manning <mmanning@...cade.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Sasha Levin <alexander.levin@...izon.com>
---
 net/ipv6/addrconf.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 8a1c846d3df9..2ec39404c449 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -303,10 +303,10 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
 	.disable_policy		= 0,
 };
 
-/* Check if a valid qdisc is available */
-static inline bool addrconf_qdisc_ok(const struct net_device *dev)
+/* Check if link is ready: is it up and is a valid qdisc available */
+static inline bool addrconf_link_ready(const struct net_device *dev)
 {
-	return !qdisc_tx_is_noop(dev);
+	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
 }
 
 static void addrconf_del_rs_timer(struct inet6_dev *idev)
@@ -451,7 +451,7 @@ static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
 
 	ndev->token = in6addr_any;
 
-	if (netif_running(dev) && addrconf_qdisc_ok(dev))
+	if (netif_running(dev) && addrconf_link_ready(dev))
 		ndev->if_flags |= IF_READY;
 
 	ipv6_mc_init_dev(ndev);
@@ -3404,7 +3404,7 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event,
 			/* restore routes for permanent addresses */
 			addrconf_permanent_addr(dev);
 
-			if (!addrconf_qdisc_ok(dev)) {
+			if (!addrconf_link_ready(dev)) {
 				/* device is not ready yet. */
 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
 					dev->name);
@@ -3419,7 +3419,7 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event,
 				run_pending = 1;
 			}
 		} else if (event == NETDEV_CHANGE) {
-			if (!addrconf_qdisc_ok(dev)) {
+			if (!addrconf_link_ready(dev)) {
 				/* device is still not ready. */
 				break;
 			}
-- 
2.11.0

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ