linux-kernel - [PATCH 3.18 090/104] bonding: fix event handling for stacked bonds

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: <20190424170909.092548995@linuxfoundation.org>
Date:   Wed, 24 Apr 2019 19:09:47 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Sabrina Dubroca <sd@...asysnail.net>,
        "David S. Miller" <davem@...emloft.net>
Subject: [PATCH 3.18 090/104] bonding: fix event handling for stacked bonds

From: Sabrina Dubroca <sd@...asysnail.net>

[ Upstream commit 92480b3977fd3884649d404cbbaf839b70035699 ]

When a bond is enslaved to another bond, bond_netdev_event() only
handles the event as if the bond is a master, and skips treating the
bond as a slave.

This leads to a refcount leak on the slave, since we don't remove the
adjacency to its master and the master holds a reference on the slave.

Reproducer:
  ip link add bondL type bond
  ip link add bondU type bond
  ip link set bondL master bondU
  ip link del bondL

No "Fixes:" tag, this code is older than git history.

Signed-off-by: Sabrina Dubroca <sd@...asysnail.net>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/net/bonding/bond_main.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2958,8 +2958,12 @@ static int bond_netdev_event(struct noti
 		return NOTIFY_DONE;
 
 	if (event_dev->flags & IFF_MASTER) {
+		int ret;
+
 		netdev_dbg(event_dev, "IFF_MASTER\n");
-		return bond_master_netdev_event(event, event_dev);
+		ret = bond_master_netdev_event(event, event_dev);
+		if (ret != NOTIFY_DONE)
+			return ret;
 	}
 
 	if (event_dev->flags & IFF_SLAVE) {