From: Ido Schimmel idosch@nvidia.com
[ Upstream commit c484fcc058bada604d7e4e5228d4affb646ddbc2 ]
When a net device is put administratively up, its 'IFF_UP' flag is set (if not set already) and a 'NETDEV_UP' notification is emitted, which causes the 8021q driver to add VLAN ID 0 on the device. The reverse happens when a net device is put administratively down.
When changing the type of a bond to Ethernet, its 'IFF_UP' flag is incorrectly cleared, resulting in the kernel skipping the above process and VLAN ID 0 being leaked [1].
Fix by restoring the flag when changing the type to Ethernet, in a similar fashion to the restoration of the 'IFF_SLAVE' flag.
The issue can be reproduced using the script in [2], with example out before and after the fix in [3].
[1] unreferenced object 0xffff888103479900 (size 256): comm "ip", pid 329, jiffies 4294775225 (age 28.561s) hex dump (first 32 bytes): 00 a0 0c 15 81 88 ff ff 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81a6051a>] kmalloc_trace+0x2a/0xe0 [<ffffffff8406426c>] vlan_vid_add+0x30c/0x790 [<ffffffff84068e21>] vlan_device_event+0x1491/0x21a0 [<ffffffff81440c8e>] notifier_call_chain+0xbe/0x1f0 [<ffffffff8372383a>] call_netdevice_notifiers_info+0xba/0x150 [<ffffffff837590f2>] __dev_notify_flags+0x132/0x2e0 [<ffffffff8375ad9f>] dev_change_flags+0x11f/0x180 [<ffffffff8379af36>] do_setlink+0xb96/0x4060 [<ffffffff837adf6a>] __rtnl_newlink+0xc0a/0x18a0 [<ffffffff837aec6c>] rtnl_newlink+0x6c/0xa0 [<ffffffff837ac64e>] rtnetlink_rcv_msg+0x43e/0xe00 [<ffffffff839a99e0>] netlink_rcv_skb+0x170/0x440 [<ffffffff839a738f>] netlink_unicast+0x53f/0x810 [<ffffffff839a7fcb>] netlink_sendmsg+0x96b/0xe90 [<ffffffff8369d12f>] ____sys_sendmsg+0x30f/0xa70 [<ffffffff836a6d7a>] ___sys_sendmsg+0x13a/0x1e0 unreferenced object 0xffff88810f6a83e0 (size 32): comm "ip", pid 329, jiffies 4294775225 (age 28.561s) hex dump (first 32 bytes): a0 99 47 03 81 88 ff ff a0 99 47 03 81 88 ff ff ..G.......G..... 81 00 00 00 01 00 00 00 cc cc cc cc cc cc cc cc ................ backtrace: [<ffffffff81a6051a>] kmalloc_trace+0x2a/0xe0 [<ffffffff84064369>] vlan_vid_add+0x409/0x790 [<ffffffff84068e21>] vlan_device_event+0x1491/0x21a0 [<ffffffff81440c8e>] notifier_call_chain+0xbe/0x1f0 [<ffffffff8372383a>] call_netdevice_notifiers_info+0xba/0x150 [<ffffffff837590f2>] __dev_notify_flags+0x132/0x2e0 [<ffffffff8375ad9f>] dev_change_flags+0x11f/0x180 [<ffffffff8379af36>] do_setlink+0xb96/0x4060 [<ffffffff837adf6a>] __rtnl_newlink+0xc0a/0x18a0 [<ffffffff837aec6c>] rtnl_newlink+0x6c/0xa0 [<ffffffff837ac64e>] rtnetlink_rcv_msg+0x43e/0xe00 [<ffffffff839a99e0>] netlink_rcv_skb+0x170/0x440 [<ffffffff839a738f>] netlink_unicast+0x53f/0x810 [<ffffffff839a7fcb>] netlink_sendmsg+0x96b/0xe90 [<ffffffff8369d12f>] ____sys_sendmsg+0x30f/0xa70 [<ffffffff836a6d7a>] ___sys_sendmsg+0x13a/0x1e0
[2] ip link add name t-nlmon type nlmon ip link add name t-dummy type dummy ip link add name t-bond type bond mode active-backup
ip link set dev t-bond up ip link set dev t-nlmon master t-bond ip link set dev t-nlmon nomaster ip link show dev t-bond ip link set dev t-dummy master t-bond ip link show dev t-bond
ip link del dev t-bond ip link del dev t-dummy ip link del dev t-nlmon
[3] Before:
12: t-bond: <NO-CARRIER,BROADCAST,MULTICAST,MASTER,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default qlen 1000 link/netlink 12: t-bond: <BROADCAST,MULTICAST,MASTER,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 46:57:39:a4:46:a2 brd ff:ff:ff:ff:ff:ff
After:
12: t-bond: <NO-CARRIER,BROADCAST,MULTICAST,MASTER,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default qlen 1000 link/netlink 12: t-bond: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000 link/ether 66:48:7b:74:b6:8a brd ff:ff:ff:ff:ff:ff
Fixes: e36b9d16c6a6 ("bonding: clean muticast addresses when device changes type") Fixes: 75c78500ddad ("bonding: remap muticast addresses without using dev_close() and dev_open()") Fixes: 9ec7eb60dcbc ("bonding: restore IFF_MASTER/SLAVE flags on bond enslave ether type change") Reported-by: Mirsad Goran Todorovac mirsad.todorovac@alu.unizg.hr Link: https://lore.kernel.org/netdev/78a8a03b-6070-3e6b-5042-f848dab16fb8@alu.uniz... Tested-by: Mirsad Goran Todorovac mirsad.todorovac@alu.unizg.hr Signed-off-by: Ido Schimmel idosch@nvidia.com Acked-by: Jay Vosburgh jay.vosburgh@canonical.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/bonding/bond_main.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index e1dc94f01cb5a..2816b6fc17392 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1746,14 +1746,15 @@ void bond_lower_state_changed(struct slave *slave)
/* The bonding driver uses ether_setup() to convert a master bond device * to ARPHRD_ETHER, that resets the target netdevice's flags so we always - * have to restore the IFF_MASTER flag, and only restore IFF_SLAVE if it was set + * have to restore the IFF_MASTER flag, and only restore IFF_SLAVE and IFF_UP + * if they were set */ static void bond_ether_setup(struct net_device *bond_dev) { - unsigned int slave_flag = bond_dev->flags & IFF_SLAVE; + unsigned int flags = bond_dev->flags & (IFF_SLAVE | IFF_UP);
ether_setup(bond_dev); - bond_dev->flags |= IFF_MASTER | slave_flag; + bond_dev->flags |= IFF_MASTER | flags; bond_dev->priv_flags &= ~IFF_TX_SKB_SHARING; }