====================================================== WARNING: possible circular locking dependency detected 4.14.171-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/1357 is trying to acquire lock: (rtnl_mutex){+.+.}, at: [] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 but task is already holding lock: (&xt[i].mutex){+.+.}, at: [] xt_find_table_lock+0x3c/0x3d0 net/netfilter/x_tables.c:1092 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&xt[i].mutex){+.+.}: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 xt_find_revision+0x82/0x200 net/netfilter/x_tables.c:373 nfnl_compat_get+0x229/0x950 net/netfilter/nft_compat.c:678 nfnetlink_rcv_msg+0xa08/0xc00 net/netfilter/nfnetlink.c:214 netlink_rcv_skb+0x14f/0x3c0 net/netlink/af_netlink.c:2432 nfnetlink_rcv+0x1ab/0x1650 net/netfilter/nfnetlink.c:515 netlink_unicast_kernel net/netlink/af_netlink.c:1286 [inline] netlink_unicast+0x44d/0x650 net/netlink/af_netlink.c:1312 netlink_sendmsg+0x7c4/0xc60 net/netlink/af_netlink.c:1877 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xce/0x110 net/socket.c:656 ___sys_sendmsg+0x70a/0x840 net/socket.c:2062 __sys_sendmsg+0xb9/0x140 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x2d/0x50 net/socket.c:2103 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #1 (&table[i].mutex){+.+.}: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 nfnl_lock+0x24/0x30 net/netfilter/nfnetlink.c:61 nf_tables_netdev_event+0x13f/0x580 net/netfilter/nf_tables_netdev.c:122 notifier_call_chain+0x111/0x1b0 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x56/0x70 net/core/dev.c:1671 call_netdevice_notifiers net/core/dev.c:1687 [inline] rollback_registered_many+0x70d/0xb60 net/core/dev.c:7205 rollback_registered+0xdd/0x180 net/core/dev.c:7247 unregister_netdevice_queue net/core/dev.c:8259 [inline] unregister_netdevice_queue+0x1ae/0x230 net/core/dev.c:8252 unregister_netdevice include/linux/netdevice.h:2442 [inline] unregister_netdev+0x1d/0x30 net/core/dev.c:8300 sixpack_close+0x158/0x1c0 drivers/net/hamradio/6pack.c:695 tty_ldisc_close.isra.0+0x99/0xd0 drivers/tty/tty_ldisc.c:505 tty_ldisc_kill+0x4b/0xc0 drivers/tty/tty_ldisc.c:651 tty_ldisc_hangup+0x29a/0x5e0 drivers/tty/tty_ldisc.c:769 __tty_hangup.part.0+0x2d3/0x6d0 drivers/tty/tty_io.c:622 __tty_hangup drivers/tty/tty_io.c:572 [inline] tty_vhangup+0x22/0x30 drivers/tty/tty_io.c:695 pty_close+0x365/0x4c0 drivers/tty/pty.c:79 tty_release+0x373/0xd60 drivers/tty/tty_io.c:1670 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #0 (rtnl_mutex){+.+.}: check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2cb3/0x4620 kernel/locking/lockdep.c:3487 lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 unregister_netdevice_notifier+0x5f/0x2c0 net/core/dev.c:1634 tee_tg_destroy+0x61/0xc0 net/netfilter/xt_TEE.c:123 cleanup_entry+0x1a6/0x260 net/ipv6/netfilter/ip6_tables.c:684 __do_replace+0x3c5/0x5c0 net/ipv6/netfilter/ip6_tables.c:1105 do_replace net/ipv6/netfilter/ip6_tables.c:1161 [inline] do_ip6t_set_ctl+0x296/0x3f4 net/ipv6/netfilter/ip6_tables.c:1685 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt net/ipv6/ipv6_sockglue.c:930 [inline] ipv6_setsockopt+0x105/0x130 net/ipv6/ipv6_sockglue.c:914 tcp_setsockopt net/ipv4/tcp.c:2826 [inline] tcp_setsockopt+0x84/0xd0 net/ipv4/tcp.c:2820 sock_common_setsockopt+0x94/0xd0 net/core/sock.c:2968 SYSC_setsockopt net/socket.c:1865 [inline] SyS_setsockopt+0x13c/0x210 net/socket.c:1844 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Chain exists of: rtnl_mutex --> &table[i].mutex --> &xt[i].mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&xt[i].mutex); lock(&table[i].mutex); lock(&xt[i].mutex); lock(rtnl_mutex); *** DEADLOCK *** 1 lock held by syz-executor.2/1357: #0: (&xt[i].mutex){+.+.}, at: [] xt_find_table_lock+0x3c/0x3d0 net/netfilter/x_tables.c:1092 stack backtrace: CPU: 1 PID: 1357 Comm: syz-executor.2 Not tainted 4.14.171-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x142/0x197 lib/dump_stack.c:58 print_circular_bug.isra.0.cold+0x1cc/0x28f kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2cb3/0x4620 kernel/locking/lockdep.c:3487 lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 unregister_netdevice_notifier+0x5f/0x2c0 net/core/dev.c:1634 tee_tg_destroy+0x61/0xc0 net/netfilter/xt_TEE.c:123 cleanup_entry+0x1a6/0x260 net/ipv6/netfilter/ip6_tables.c:684 __do_replace+0x3c5/0x5c0 net/ipv6/netfilter/ip6_tables.c:1105 do_replace net/ipv6/netfilter/ip6_tables.c:1161 [inline] do_ip6t_set_ctl+0x296/0x3f4 net/ipv6/netfilter/ip6_tables.c:1685 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt net/ipv6/ipv6_sockglue.c:930 [inline] ipv6_setsockopt+0x105/0x130 net/ipv6/ipv6_sockglue.c:914 tcp_setsockopt net/ipv4/tcp.c:2826 [inline] tcp_setsockopt+0x84/0xd0 net/ipv4/tcp.c:2820 sock_common_setsockopt+0x94/0xd0 net/core/sock.c:2968 SYSC_setsockopt net/socket.c:1865 [inline] SyS_setsockopt+0x13c/0x210 net/socket.c:1844 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c429 RSP: 002b:00007f36bec63c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f36bec646d4 RCX: 000000000045c429 RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000400 R09: 0000000000000000 R10: 0000000020000880 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000a32 R14: 00000000004d5b90 R15: 000000000076bf2c ip6_tables: ip6tables: counters copy to user failed while replacing table nla_parse: 38 callbacks suppressed netlink: 40795 bytes leftover after parsing attributes in process `syz-executor.4'. ip6_tables: ip6tables: counters copy to user failed while replacing table ip6_tables: ip6tables: counters copy to user failed while replacing table netlink: 40795 bytes leftover after parsing attributes in process `syz-executor.4'. ip6_tables: ip6tables: counters copy to user failed while replacing table ip6_tables: ip6tables: counters copy to user failed while replacing table ip6_tables: ip6tables: counters copy to user failed while replacing table netlink: 40795 bytes leftover after parsing attributes in process `syz-executor.4'. ip6_tables: ip6tables: counters copy to user failed while replacing table netlink: 40795 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 208 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 208 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 208 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 208 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 208 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 208 bytes leftover after parsing attributes in process `syz-executor.2'. device bond8 entered promiscuous mode device bridge1 entered promiscuous mode bond8: Enslaving bridge1 as an active interface with an up link device bond9 entered promiscuous mode device bond10 entered promiscuous mode device bond9 entered promiscuous mode device bridge4 entered promiscuous mode bond10: Enslaving bridge4 as an active interface with an up link device bridge1 entered promiscuous mode bond9: Enslaving bridge1 as an active interface with an up link device bond1 entered promiscuous mode device bridge1 entered promiscuous mode bond1: Enslaving bridge1 as an active interface with an up link device bond11 entered promiscuous mode device bridge5 entered promiscuous mode bond11: Enslaving bridge5 as an active interface with an up link device bond10 entered promiscuous mode device bridge2 entered promiscuous mode bond10: Enslaving bridge2 as an active interface with an up link device bond2 entered promiscuous mode device bond12 entered promiscuous mode device bridge2 entered promiscuous mode bond2: Enslaving bridge2 as an active interface with an up link device bridge6 entered promiscuous mode bond12: Enslaving bridge6 as an active interface with an up link device bond11 entered promiscuous mode device bridge3 entered promiscuous mode bond11: Enslaving bridge3 as an active interface with an up link sched: RT throttling activated