3.16.62-rc1 review patch. If anyone has any objections, please let me know.
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From: Ido Schimmel idosch@mellanox.com
commit 471b83bd8bbe4e89743683ef8ecb78f7029d8288 upstream.
team's ndo_add_slave() acquires 'team->lock' and later tries to open the newly enslaved device via dev_open(). This emits a 'NETDEV_UP' event that causes the VLAN driver to add VLAN 0 on the team device. team's ndo_vlan_rx_add_vid() will also try to acquire 'team->lock' and deadlock.
Fix this by checking early at the enslavement function that a team device is not being enslaved to itself.
A similar check was added to the bond driver in commit 09a89c219baf ("bonding: disallow enslaving a bond to itself").
WARNING: possible recursive locking detected 4.18.0-rc7+ #176 Not tainted -------------------------------------------- syz-executor4/6391 is trying to acquire lock: (____ptrval____) (&team->lock){+.+.}, at: team_vlan_rx_add_vid+0x3b/0x1e0 drivers/net/team/team.c:1868
but task is already holding lock: (____ptrval____) (&team->lock){+.+.}, at: team_add_slave+0xdb/0x1c30 drivers/net/team/team.c:1947
other info that might help us debug this: Possible unsafe locking scenario:
CPU0 ---- lock(&team->lock); lock(&team->lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
2 locks held by syz-executor4/6391: #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x412/0xc30 net/core/rtnetlink.c:4662 #1: (____ptrval____) (&team->lock){+.+.}, at: team_add_slave+0xdb/0x1c30 drivers/net/team/team.c:1947
stack backtrace: CPU: 1 PID: 6391 Comm: syz-executor4 Not tainted 4.18.0-rc7+ #176 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 print_deadlock_bug kernel/locking/lockdep.c:1765 [inline] check_deadlock kernel/locking/lockdep.c:1809 [inline] validate_chain kernel/locking/lockdep.c:2405 [inline] __lock_acquire.cold.64+0x1fb/0x486 kernel/locking/lockdep.c:3435 lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924 __mutex_lock_common kernel/locking/mutex.c:757 [inline] __mutex_lock+0x176/0x1820 kernel/locking/mutex.c:894 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:909 team_vlan_rx_add_vid+0x3b/0x1e0 drivers/net/team/team.c:1868 vlan_add_rx_filter_info+0x14a/0x1d0 net/8021q/vlan_core.c:210 __vlan_vid_add net/8021q/vlan_core.c:278 [inline] vlan_vid_add+0x63e/0x9d0 net/8021q/vlan_core.c:308 vlan_device_event.cold.12+0x2a/0x2f net/8021q/vlan.c:381 notifier_call_chain+0x180/0x390 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735 call_netdevice_notifiers net/core/dev.c:1753 [inline] dev_open+0x173/0x1b0 net/core/dev.c:1433 team_port_add drivers/net/team/team.c:1219 [inline] team_add_slave+0xa8b/0x1c30 drivers/net/team/team.c:1948 do_set_master+0x1c9/0x220 net/core/rtnetlink.c:2248 do_setlink+0xba4/0x3e10 net/core/rtnetlink.c:2382 rtnl_setlink+0x2a9/0x400 net/core/rtnetlink.c:2636 rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4665 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2455 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4683 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline] netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1343 netlink_sendmsg+0xa18/0xfd0 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:642 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:652 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2126 __sys_sendmsg+0x11d/0x290 net/socket.c:2164 __do_sys_sendmsg net/socket.c:2173 [inline] __se_sys_sendmsg net/socket.c:2171 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2171 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456b29 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f9706bf8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f9706bf96d4 RCX: 0000000000456b29 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000004 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d3548 R14: 00000000004c8227 R15: 0000000000000000
Fixes: 87002b03baab ("net: introduce vlan_vid_[add/del] and use them instead of direct [add/kill]_vid ndo calls") Signed-off-by: Ido Schimmel idosch@mellanox.com Reported-and-tested-by: syzbot+bd051aba086537515cdb@syzkaller.appspotmail.com Signed-off-by: David S. Miller davem@davemloft.net [bwh: Backported to 3.16: drop the extack message] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -1124,6 +1124,11 @@ static int team_port_add(struct team *te return -EBUSY; }
+ if (dev == port_dev) { + netdev_err(dev, "Cannot enslave team device to itself\n"); + return -EINVAL; + } + if (port_dev->features & NETIF_F_VLAN_CHALLENGED && vlan_uses_dev(dev)) { netdev_err(dev, "Device %s is VLAN challenged and team device has VLAN set up\n",