From 0d0ca85ad4241c83abd10a61070353f53dd8023f Mon Sep 17 00:00:00 2001 From: Taehee Yoo Date: Mon, 21 Oct 2019 18:47:52 +0000 Subject: [PATCH] bonding: fix unexpected IFF_BONDING bit unset [ Upstream commit 65de65d9033750d2cf1b336c9d6e9da3a8b5cc6e ] The IFF_BONDING means bonding master or bonding slave device. ->ndo_add_slave() sets IFF_BONDING flag and ->ndo_del_slave() unsets IFF_BONDING flag. bond0<--bond1 Both bond0 and bond1 are bonding device and these should keep having IFF_BONDING flag until they are removed. But bond1 would lose IFF_BONDING at ->ndo_del_slave() because that routine do not check whether the slave device is the bonding type or not. This patch adds the interface type check routine before removing IFF_BONDING flag. Test commands: ip link add bond0 type bond ip link add bond1 type bond ip link set bond1 master bond0 ip link set bond1 nomaster ip link del bond1 type bond ip link add bond1 type bond Splat looks like: [ 226.665555] proc_dir_entry 'bonding/bond1' already registered [ 226.666440] WARNING: CPU: 0 PID: 737 at fs/proc/generic.c:361 proc_register+0x2a9/0x3e0 [ 226.667571] Modules linked in: bonding af_packet sch_fq_codel ip_tables x_tables unix [ 226.668662] CPU: 0 PID: 737 Comm: ip Not tainted 5.4.0-rc3+ #96 [ 226.669508] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 226.670652] RIP: 0010:proc_register+0x2a9/0x3e0 [ 226.671612] Code: 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 39 01 00 00 48 8b 04 24 48 89 ea 48 c7 c7 a0 0b 14 9f 48 8b b0 e 0 00 00 00 e8 07 e7 88 ff <0f> 0b 48 c7 c7 40 2d a5 9f e8 59 d6 23 01 48 8b 4c 24 10 48 b8 00 [ 226.675007] RSP: 0018:ffff888050e17078 EFLAGS: 00010282 [ 226.675761] RAX: dffffc0000000008 RBX: ffff88805fdd0f10 RCX: ffffffff9dd344e2 [ 226.676757] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88806c9f6b8c [ 226.677751] RBP: ffff8880507160f3 R08: ffffed100d940019 R09: ffffed100d940019 [ 226.678761] R10: 0000000000000001 R11: ffffed100d940018 R12: ffff888050716008 [ 226.679757] R13: ffff8880507160f2 R14: dffffc0000000000 R15: ffffed100a0e2c1e [ 226.680758] FS: 00007fdc217cc0c0(0000) GS:ffff88806c800000(0000) knlGS:0000000000000000 [ 226.681886] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 226.682719] CR2: 00007f49313424d0 CR3: 0000000050e46001 CR4: 00000000000606f0 [ 226.683727] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 226.684725] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 226.685681] Call Trace: [ 226.687089] proc_create_seq_private+0xb3/0xf0 [ 226.687778] bond_create_proc_entry+0x1b3/0x3f0 [bonding] [ 226.691458] bond_netdev_event+0x433/0x970 [bonding] [ 226.692139] ? __module_text_address+0x13/0x140 [ 226.692779] notifier_call_chain+0x90/0x160 [ 226.693401] register_netdevice+0x9b3/0xd80 [ 226.694010] ? alloc_netdev_mqs+0x854/0xc10 [ 226.694629] ? netdev_change_features+0xa0/0xa0 [ 226.695278] ? rtnl_create_link+0x2ed/0xad0 [ 226.695849] bond_newlink+0x2a/0x60 [bonding] [ 226.696422] __rtnl_newlink+0xb9f/0x11b0 [ 226.696968] ? rtnl_link_unregister+0x220/0x220 [ ... ] Fixes: 0b680e753724 ("[PATCH] bonding: Add priv_flag to avoid event mishandling") Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/bonding/bond_main.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 136a972ea903..9b8143dca512 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1798,7 +1798,8 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev, slave_disable_netpoll(new_slave); err_close: - slave_dev->priv_flags &= ~IFF_BONDING; + if (!netif_is_bond_master(slave_dev)) + slave_dev->priv_flags &= ~IFF_BONDING; dev_close(slave_dev); err_restore_mac: @@ -2004,7 +2005,8 @@ static int __bond_release_one(struct net_device *bond_dev, else dev_set_mtu(slave_dev, slave->original_mtu); - slave_dev->priv_flags &= ~IFF_BONDING; + if (!netif_is_bond_master(slave_dev)) + slave_dev->priv_flags &= ~IFF_BONDING; bond_free_slave(slave); -- GitLab