netdev - [PATCH net-next] bonding: don't permit slaves to change their mtu

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-next>] [day] [month] [year] [list]

Message-ID: <52D4A8A7.60100@huawei.com>
Date:	Tue, 14 Jan 2014 11:01:59 +0800
From:	Ding Tianhong <dingtianhong@...wei.com>
To:	Jay Vosburgh <fubar@...ibm.com>,
	Veaceslav Falico <vfalico@...hat.com>,
	"David S. Miller" <davem@...emloft.net>,
	Netdev <netdev@...r.kernel.org>
Subject: [PATCH net-next] bonding: don't permit slaves to change their mtu

The commit 2315dc91a5059d7da9a8b9b9daf78d695c11383e
(net: make dev_set_mtu() honor notification return code)
will deal with the return value for NETDEV_CHANGEMTU notification,
and the slaves should not change their mtu, so add return value
to prevent doing it.

Suggested-by: Veaceslav Falico <vfalico@...hat.com>
Signed-off-by: Ding Tianhong <dingtianhong@...wei.com>
---
 drivers/net/bonding/bond_main.c | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index e06c445..af4e678 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2846,19 +2846,11 @@ static int bond_slave_netdev_event(unsigned long event,
 		 */
 		break;
 	case NETDEV_CHANGEMTU:
-		/*
-		 * TODO: Should slaves be allowed to
-		 * independently alter their MTU?  For
-		 * an active-backup bond, slaves need
-		 * not be the same type of device, so
-		 * MTUs may vary.  For other modes,
-		 * slaves arguably should have the
-		 * same MTUs. To do this, we'd need to
-		 * take over the slave's change_mtu
-		 * function for the duration of their
-		 * servitude.
+		/* The master and slaves should have the
+		 * the same mtu, so do't permit slaves
+		 * to change their mtu independently.
 		 */
-		break;
+		return NOTIFY_BAD;
 	case NETDEV_CHANGENAME:
 		/*
 		 * TODO: handle changing the primary's name
-- 
1.8.0


--
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