====================================================== WARNING: possible circular locking dependency detected 4.15.0-rc9+ #212 Not tainted ------------------------------------------------------ syz-executor2/5879 is trying to acquire lock: (&xt[i].mutex){+.+.}, at: [<00000000c212eaa7>] xt_find_target+0x44/0x1e0 net/netfilter/x_tables.c:229 but task is already holding lock: (sk_lock-AF_INET6){+.+.}, at: [<000000001f69abdb>] lock_sock include/net/sock.h:1463 [inline] (sk_lock-AF_INET6){+.+.}, at: [<000000001f69abdb>] ipv6_setsockopt+0xff/0x150 net/ipv6/ipv6_sockglue.c:927 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sk_lock-AF_INET6){+.+.}: lock_sock_nested+0xc2/0x110 net/core/sock.c:2780 lock_sock include/net/sock.h:1463 [inline] do_ipv6_setsockopt.isra.8+0x3c5/0x39d0 net/ipv6/ipv6_sockglue.c:167 ipv6_setsockopt+0xd7/0x150 net/ipv6/ipv6_sockglue.c:922 sctp_setsockopt+0x2b6/0x61d0 net/sctp/socket.c:4141 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2978 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 entry_SYSCALL_64_fastpath+0x29/0xa0 -> #1 (rtnl_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 unregister_netdevice_notifier+0x91/0x4e0 net/core/dev.c:1673 clusterip_config_entry_put net/ipv4/netfilter/ipt_CLUSTERIP.c:114 [inline] clusterip_tg_destroy+0x389/0x6e0 net/ipv4/netfilter/ipt_CLUSTERIP.c:508 cleanup_entry+0x218/0x350 net/ipv4/netfilter/ip_tables.c:659 __do_replace+0x79d/0xa50 net/ipv4/netfilter/ip_tables.c:1094 do_replace net/ipv4/netfilter/ip_tables.c:1150 [inline] do_ipt_set_ctl+0x40f/0x5f0 net/ipv4/netfilter/ip_tables.c:1680 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ip_setsockopt+0xa1/0xb0 net/ipv4/ip_sockglue.c:1260 sctp_setsockopt+0x2b6/0x61d0 net/sctp/socket.c:4141 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2978 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 entry_SYSCALL_64_fastpath+0x29/0xa0 -> #0 (&xt[i].mutex){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3914 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 xt_find_target+0x44/0x1e0 net/netfilter/x_tables.c:229 xt_request_find_target+0x2c/0xb0 net/netfilter/x_tables.c:255 find_check_entry.isra.7+0x669/0xcf0 net/ipv6/netfilter/ip6_tables.c:572 translate_table+0xf52/0x1690 net/ipv6/netfilter/ip6_tables.c:749 do_replace net/ipv6/netfilter/ip6_tables.c:1165 [inline] do_ip6t_set_ctl+0x370/0x5f0 net/ipv6/netfilter/ip6_tables.c:1691 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt+0x115/0x150 net/ipv6/ipv6_sockglue.c:928 tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2872 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2978 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 entry_SYSCALL_64_fastpath+0x29/0xa0 other info that might help us debug this: Chain exists of: &xt[i].mutex --> rtnl_mutex --> sk_lock-AF_INET6 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_INET6); lock(rtnl_mutex); lock(sk_lock-AF_INET6); lock(&xt[i].mutex); *** DEADLOCK *** 1 lock held by syz-executor2/5879: #0: (sk_lock-AF_INET6){+.+.}, at: [<000000001f69abdb>] lock_sock include/net/sock.h:1463 [inline] #0: (sk_lock-AF_INET6){+.+.}, at: [<000000001f69abdb>] ipv6_setsockopt+0xff/0x150 net/ipv6/ipv6_sockglue.c:927 stack backtrace: CPU: 1 PID: 5879 Comm: syz-executor2 Not tainted 4.15.0-rc9+ #212 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+0x194/0x257 lib/dump_stack.c:53 print_circular_bug.isra.37+0x2cd/0x2dc kernel/locking/lockdep.c:1218 check_prev_add kernel/locking/lockdep.c:1858 [inline] check_prevs_add kernel/locking/lockdep.c:1971 [inline] validate_chain kernel/locking/lockdep.c:2412 [inline] __lock_acquire+0x30a8/0x3e00 kernel/locking/lockdep.c:3426 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3914 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 xt_find_target+0x44/0x1e0 net/netfilter/x_tables.c:229 xt_request_find_target+0x2c/0xb0 net/netfilter/x_tables.c:255 find_check_entry.isra.7+0x669/0xcf0 net/ipv6/netfilter/ip6_tables.c:572 translate_table+0xf52/0x1690 net/ipv6/netfilter/ip6_tables.c:749 do_replace net/ipv6/netfilter/ip6_tables.c:1165 [inline] do_ip6t_set_ctl+0x370/0x5f0 net/ipv6/netfilter/ip6_tables.c:1691 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt+0x115/0x150 net/ipv6/ipv6_sockglue.c:928 tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2872 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2978 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 entry_SYSCALL_64_fastpath+0x29/0xa0 RIP: 0033:0x453299 RSP: 002b:00007f9b48924c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000453299 RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000013 RBP: 00000000000005c5 R08: 00000000000003e0 R09: 0000000000000000 R10: 0000000020002000 R11: 0000000000000212 R12: 00000000006f7b18 R13: 00000000ffffffff R14: 00007f9b489256d4 R15: 0000000000000000 xt_CT: netfilter: NOTRACK target is deprecated, use CT instead or upgrade iptables xt_CT: No such helper "snmp" can: request_module (can-proto-0) failed. can: request_module (can-proto-0) failed. netlink: 10 bytes leftover after parsing attributes in process `syz-executor0'. xt_CT: netfilter: NOTRACK target is deprecated, use CT instead or upgrade iptables xt_CT: No such timeout policy "syz1" xt_CT: No such timeout policy "syz1" netlink: 10 bytes leftover after parsing attributes in process `syz-executor0'. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=17328 sclass=netlink_route_socket pig=6044 comm=syz-executor7 sock: sock_set_timeout: `syz-executor5' (pid 6041) tries to set negative timeout SELinux: unrecognized netlink message: protocol=0 nlmsg_type=17328 sclass=netlink_route_socket pig=6044 comm=syz-executor7 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=11553 sclass=netlink_route_socket pig=6168 comm=syz-executor2 Protocol error: SET target dimension is over the limit! SELinux: unrecognized netlink message: protocol=0 nlmsg_type=11553 sclass=netlink_route_socket pig=6173 comm=syz-executor2 Protocol error: SET target dimension is over the limit! KCM: Hard failure on kcm_write_msgs -2147483648 kauditd_printk_skb: 10 callbacks suppressed audit: type=1400 audit(1517093323.555:39): avc: denied { bind } for pid=6327 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1 ip_tunnel: non-ECT from 0.0.0.0 with TOS=0x3 ip_tunnel: non-ECT from 0.0.0.0 with TOS=0x3 sctp: [Deprecated]: syz-executor2 (pid 6456) Use of struct sctp_assoc_value in delayed_ack socket option. Use struct sctp_sack_info instead sctp: [Deprecated]: syz-executor2 (pid 6456) Use of struct sctp_assoc_value in delayed_ack socket option. Use struct sctp_sack_info instead l2tp_core: tunl 59: sockfd_lookup(fd=0) returned -88 l2tp_core: tunl 59: sockfd_lookup(fd=0) returned -88 netlink: 'syz-executor3': attribute type 1 has an invalid length. netlink: 'syz-executor3': attribute type 1 has an invalid length. syz1: Invalid MTU 1 requested, hw min 68 syz1: Invalid MTU 1 requested, hw min 68 device lo entered promiscuous mode audit: type=1400 audit(1517093324.634:40): avc: denied { create } for pid=6751 comm="syz-executor5" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_fib_lookup_socket permissive=1 audit: type=1400 audit(1517093324.670:41): avc: denied { write } for pid=6751 comm="syz-executor5" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_fib_lookup_socket permissive=1 audit: type=1400 audit(1517093324.751:42): avc: denied { setopt } for pid=6786 comm="syz-executor5" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:unlabeled_t:s0 tclass=socket permissive=1 netlink: 'syz-executor1': attribute type 1 has an invalid length. netlink: 'syz-executor1': attribute type 1 has an invalid length. audit: type=1400 audit(1517093325.118:43): avc: denied { setopt } for pid=6946 comm="syz-executor1" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1 xt_cgroup: no path or classid specified xt_cgroup: no path or classid specified audit: type=1400 audit(1517093325.441:44): avc: denied { net_broadcast } for pid=7074 comm="syz-executor4" capability=11 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1517093325.840:45): avc: denied { setopt } for pid=7236 comm="syz-executor0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 audit: type=1400 audit(1517093325.840:46): avc: denied { getattr } for pid=7236 comm="syz-executor0" path="socket:[16990]" dev="sockfs" ino=16990 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 netlink: 2 bytes leftover after parsing attributes in process `syz-executor2'. audit: type=1400 audit(1517093325.903:47): avc: denied { write } for pid=7264 comm="syz-executor2" path="socket:[17019]" dev="sockfs" ino=17019 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_connector_socket permissive=1