EXT4-fs (loop4): mounted filesystem without journal. Opts: ,errors=continue ====================================================== WARNING: possible circular locking dependency detected 4.14.262-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:3/896 is trying to acquire lock: (&table[i].mutex){+.+.}, at: [] nf_tables_netdev_event+0x10d/0x4d0 net/netfilter/nf_tables_netdev.c:122 but task is already holding lock: (rtnl_mutex){+.+.}, at: [] ip6gre_exit_net+0x70/0x570 net/ipv6/ip6_gre.c:1207 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (rtnl_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 unregister_netdevice_notifier+0x5e/0x2b0 net/core/dev.c:1630 tee_tg_destroy+0x5c/0xb0 net/netfilter/xt_TEE.c:123 cleanup_entry+0x1fd/0x2d0 net/ipv4/netfilter/ip_tables.c:666 __do_replace+0x38d/0x570 net/ipv4/netfilter/ip_tables.c:1086 do_replace net/ipv4/netfilter/ip_tables.c:1142 [inline] do_ipt_set_ctl+0x256/0x3a0 net/ipv4/netfilter/ip_tables.c:1676 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x5f/0xb0 net/netfilter/nf_sockopt.c:115 ip_setsockopt net/ipv4/ip_sockglue.c:1255 [inline] ip_setsockopt+0x94/0xb0 net/ipv4/ip_sockglue.c:1240 tcp_setsockopt+0x7b/0xc0 net/ipv4/tcp.c:2828 SYSC_setsockopt net/socket.c:1865 [inline] SyS_setsockopt+0x110/0x1e0 net/socket.c:1844 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #1 (&xt[i].mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 target_revfn+0x43/0x210 net/netfilter/x_tables.c:354 xt_find_revision+0x15e/0x1d0 net/netfilter/x_tables.c:378 nfnl_compat_get+0x1f7/0x870 net/netfilter/nft_compat.c:678 nfnetlink_rcv_msg+0x9bb/0xc00 net/netfilter/nfnetlink.c:214 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2446 nfnetlink_rcv+0x1ab/0x1da0 net/netfilter/nfnetlink.c:515 netlink_unicast_kernel net/netlink/af_netlink.c:1294 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1320 netlink_sendmsg+0x648/0xbc0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062 __sys_sendmsg+0xa3/0x120 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x27/0x40 net/socket.c:2103 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #0 (&table[i].mutex){+.+.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 nf_tables_netdev_event+0x10d/0x4d0 net/netfilter/nf_tables_netdev.c:122 notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93 call_netdevice_notifiers_info net/core/dev.c:1667 [inline] call_netdevice_notifiers net/core/dev.c:1683 [inline] rollback_registered_many+0x765/0xba0 net/core/dev.c:7211 unregister_netdevice_many.part.0+0x18/0x2e0 net/core/dev.c:8293 unregister_netdevice_many+0x36/0x50 net/core/dev.c:8292 ip6gre_exit_net+0x41e/0x570 net/ipv6/ip6_gre.c:1209 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:142 cleanup_net+0x3b3/0x840 net/core/net_namespace.c:485 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 other info that might help us debug this: Chain exists of: &table[i].mutex --> &xt[i].mutex --> rtnl_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(&xt[i].mutex); lock(rtnl_mutex); lock(&table[i].mutex); *** DEADLOCK *** 4 locks held by kworker/u4:3/896: #0: ("%s""netns"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088 #1: (net_cleanup_work){+.+.}, at: [] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092 #2: (net_mutex){+.+.}, at: [] cleanup_net+0x110/0x840 net/core/net_namespace.c:451 #3: (rtnl_mutex){+.+.}, at: [] ip6gre_exit_net+0x70/0x570 net/ipv6/ip6_gre.c:1207 stack backtrace: CPU: 1 PID: 896 Comm: kworker/u4:3 Not tainted 4.14.262-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 nf_tables_netdev_event+0x10d/0x4d0 net/netfilter/nf_tables_netdev.c:122 notifier_call_chain+0x108/0x1a0 kernel/notifier.c:93 call_netdevice_notifiers_info net/core/dev.c:1667 [inline] call_netdevice_notifiers net/core/dev.c:1683 [inline] rollback_registered_many+0x765/0xba0 net/core/dev.c:7211 unregister_netdevice_many.part.0+0x18/0x2e0 net/core/dev.c:8293 unregister_netdevice_many+0x36/0x50 net/core/dev.c:8292 ip6gre_exit_net+0x41e/0x570 net/ipv6/ip6_gre.c:1209 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:142 cleanup_net+0x3b3/0x840 net/core/net_namespace.c:485 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. syz-executor.2 (10281) used greatest stack depth: 24200 bytes left IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready netlink: 14 bytes leftover after parsing attributes in process `syz-executor.1'. bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state device bridge0 entered promiscuous mode netlink: 14 bytes leftover after parsing attributes in process `syz-executor.1'. bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state audit: type=1800 audit(1641928037.754:10): pid=10577 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="loop0" ino=3 res=0 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered forwarding state bridge0: port 1(bridge_slave_0) entered blocking state bridge0: port 1(bridge_slave_0) entered forwarding state bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state audit: type=1800 audit(1641928038.884:11): pid=10674 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="loop0" ino=4 res=0 audit: type=1800 audit(1641928040.264:12): pid=10724 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="loop0" ino=5 res=0 nla_parse: 5 callbacks suppressed netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. audit: type=1800 audit(1641928041.934:13): pid=10763 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.0" name="bus" dev="loop0" ino=6 res=0 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'.