syzbot

======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc6-syzkaller-01313-g23c9ff659140 #0 Not tainted
------------------------------------------------------
syz.3.696/8344 is trying to acquire lock:
ffff888079afcd28 (&dev_instance_lock_key#12){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
ffff888079afcd28 (&dev_instance_lock_key#12){+.+.}-{4:4}, at: dev_set_mac_address+0x2a/0x50 net/core/dev_api.c:302

but task is already holding lock:
ffff88805ec8cd28 (&dev_instance_lock_key#2){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
ffff88805ec8cd28 (&dev_instance_lock_key#2){+.+.}-{4:4}, at: do_setlink+0xa94/0x40f0 net/core/rtnetlink.c:3094

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&dev_instance_lock_key#2){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       netdev_lock include/linux/netdevice.h:2731 [inline]
       netif_set_up net/core/dev.h:143 [inline]
       __dev_open+0x5cb/0x8a0 net/core/dev.c:1651
       netif_open+0xae/0x1b0 net/core/dev.c:1667
       dev_open+0x13e/0x260 net/core/dev_api.c:191
       team_port_add drivers/net/team/team_core.c:1230 [inline]
       team_add_slave+0xabe/0x28a0 drivers/net/team/team_core.c:1989
       do_set_master+0x579/0x730 net/core/rtnetlink.c:2943
       rtnl_newlink_create+0x6e6/0xbd0 net/core/rtnetlink.c:3837
       __rtnl_newlink net/core/rtnetlink.c:3940 [inline]
       rtnl_newlink+0x167a/0x1d90 net/core/rtnetlink.c:4055
       rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
       netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
       netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
       netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
       netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:709 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:724
       ____sys_sendmsg+0x53a/0x860 net/socket.c:2564
       ___sys_sendmsg net/socket.c:2618 [inline]
       __sys_sendmsg+0x269/0x350 net/socket.c:2650
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (team->team_lock_key#5){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       team_set_mac_address+0x122/0x280 drivers/net/team/team_core.c:1817
       netif_set_mac_address+0x327/0x510 net/core/dev.c:9590
       do_setlink+0xaa6/0x40f0 net/core/rtnetlink.c:3095
       rtnl_changelink net/core/rtnetlink.c:3759 [inline]
       __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
       rtnl_newlink+0x15a6/0x1d90 net/core/rtnetlink.c:4055
       rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
       netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
       netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
       netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
       netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:709 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:724
       __sys_sendto+0x363/0x4c0 net/socket.c:2178
       __do_sys_sendto net/socket.c:2185 [inline]
       __se_sys_sendto net/socket.c:2181 [inline]
       __x64_sys_sendto+0xde/0x100 net/socket.c:2181
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&dev_instance_lock_key#12){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       netdev_lock include/linux/netdevice.h:2731 [inline]
       dev_set_mac_address+0x2a/0x50 net/core/dev_api.c:302
       bond_set_mac_address+0x28e/0x830 drivers/net/bonding/bond_main.c:4903
       netif_set_mac_address+0x327/0x510 net/core/dev.c:9590
       do_setlink+0xaa6/0x40f0 net/core/rtnetlink.c:3095
       rtnl_changelink net/core/rtnetlink.c:3759 [inline]
       __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
       rtnl_newlink+0x15a6/0x1d90 net/core/rtnetlink.c:4055
       rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
       netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
       netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
       netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
       netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
       sock_sendmsg_nosec net/socket.c:709 [inline]
       __sock_sendmsg+0x221/0x270 net/socket.c:724
       ____sys_sendmsg+0x53a/0x860 net/socket.c:2564
       ___sys_sendmsg net/socket.c:2618 [inline]
       __sys_sendmsg+0x269/0x350 net/socket.c:2650
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &dev_instance_lock_key#12 --> team->team_lock_key#5 --> &dev_instance_lock_key#2

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&dev_instance_lock_key#2);
                               lock(team->team_lock_key#5);
                               lock(&dev_instance_lock_key#2);
  lock(&dev_instance_lock_key#12);

 *** DEADLOCK ***

2 locks held by syz.3.696/8344:
 #0: ffffffff8fed6e08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8fed6e08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8fed6e08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc4c/0x1d90 net/core/rtnetlink.c:4054
 #1: ffff88805ec8cd28 (&dev_instance_lock_key#2){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2731 [inline]
 #1: ffff88805ec8cd28 (&dev_instance_lock_key#2){+.+.}-{4:4}, at: do_setlink+0xa94/0x40f0 net/core/rtnetlink.c:3094

stack backtrace:
CPU: 1 UID: 0 PID: 8344 Comm: syz.3.696 Not tainted 6.14.0-rc6-syzkaller-01313-g23c9ff659140 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
 netdev_lock include/linux/netdevice.h:2731 [inline]
 dev_set_mac_address+0x2a/0x50 net/core/dev_api.c:302
 bond_set_mac_address+0x28e/0x830 drivers/net/bonding/bond_main.c:4903
 netif_set_mac_address+0x327/0x510 net/core/dev.c:9590
 do_setlink+0xaa6/0x40f0 net/core/rtnetlink.c:3095
 rtnl_changelink net/core/rtnetlink.c:3759 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3918 [inline]
 rtnl_newlink+0x15a6/0x1d90 net/core/rtnetlink.c:4055
 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6945
 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:709 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:724
 ____sys_sendmsg+0x53a/0x860 net/socket.c:2564
 ___sys_sendmsg net/socket.c:2618 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2650
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f623ed8d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f623cbd5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f623efa6080 RCX: 00007f623ed8d169
RDX: 0000000000040880 RSI: 0000400000000000 RDI: 0000000000000006
RBP: 00007f623ee0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f623efa6080 R15: 00007ffe205ae068
 </TASK>
bond0: entered promiscuous mode
bond_slave_0: entered promiscuous mode
bond_slave_1: entered promiscuous mode
team0: entered promiscuous mode
team_slave_0: entered promiscuous mode
team_slave_1: entered promiscuous mode