====================================================== WARNING: possible circular locking dependency detected 4.16.0-rc2+ #326 Not tainted ------------------------------------------------------ syz-executor4/6230 is trying to acquire lock: (sk_lock-AF_INET){+.+.}, at: [<0000000046142be2>] lock_sock include/net/sock.h:1463 [inline] (sk_lock-AF_INET){+.+.}, at: [<0000000046142be2>] do_ip_getsockopt+0x1b3/0x2170 net/ipv4/ip_sockglue.c:1329 but task is already holding lock: (rtnl_mutex){+.+.}, at: [<00000000fedb31d3>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 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+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 tee_tg_destroy+0x61/0xc0 net/netfilter/xt_TEE.c:123 cleanup_entry+0x242/0x380 net/ipv6/netfilter/ip6_tables.c:673 __do_replace+0x7ac/0xa70 net/ipv6/netfilter/ip6_tables.c:1108 do_replace net/ipv6/netfilter/ip6_tables.c:1164 [inline] do_ip6t_set_ctl+0x40f/0x5f0 net/ipv6/netfilter/ip6_tables.c:1686 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt+0x10b/0x130 net/ipv6/ipv6_sockglue.c:927 dccp_setsockopt+0x85/0xd0 net/dccp/proto.c:576 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975 SYSC_setsockopt net/socket.c:1849 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1828 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #1 (&xt[i].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 xt_find_table_lock+0x3e/0x3e0 net/netfilter/x_tables.c:1046 xt_request_find_table_lock+0x28/0xc0 net/netfilter/x_tables.c:1093 get_info+0x154/0x690 net/ipv6/netfilter/ip6_tables.c:989 do_arpt_get_ctl+0x2a9/0xa00 net/ipv4/netfilter/arp_tables.c:1481 nf_sockopt net/netfilter/nf_sockopt.c:104 [inline] nf_getsockopt+0x6a/0xc0 net/netfilter/nf_sockopt.c:122 ip_getsockopt+0x15c/0x220 net/ipv4/ip_sockglue.c:1571 tcp_getsockopt+0x82/0xd0 net/ipv4/tcp.c:3359 sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2934 SYSC_getsockopt net/socket.c:1880 [inline] SyS_getsockopt+0x178/0x340 net/socket.c:1862 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #0 (sk_lock-AF_INET){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 lock_sock_nested+0xc2/0x110 net/core/sock.c:2777 lock_sock include/net/sock.h:1463 [inline] do_ip_getsockopt+0x1b3/0x2170 net/ipv4/ip_sockglue.c:1329 ip_getsockopt+0x90/0x220 net/ipv4/ip_sockglue.c:1560 tcp_getsockopt+0x82/0xd0 net/ipv4/tcp.c:3359 sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2934 SYSC_getsockopt net/socket.c:1880 [inline] SyS_getsockopt+0x178/0x340 net/socket.c:1862 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Chain exists of: sk_lock-AF_INET --> &xt[i].mutex --> rtnl_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(&xt[i].mutex); lock(rtnl_mutex); lock(sk_lock-AF_INET); *** DEADLOCK *** 1 lock held by syz-executor4/6230: #0: (rtnl_mutex){+.+.}, at: [<00000000fedb31d3>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74 stack backtrace: CPU: 1 PID: 6230 Comm: syz-executor4 Not tainted 4.16.0-rc2+ #326 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+0x194/0x24d lib/dump_stack.c:53 print_circular_bug.isra.38+0x2cd/0x2dc kernel/locking/lockdep.c:1223 check_prev_add kernel/locking/lockdep.c:1863 [inline] check_prevs_add kernel/locking/lockdep.c:1976 [inline] validate_chain kernel/locking/lockdep.c:2417 [inline] __lock_acquire+0x30a8/0x3e00 kernel/locking/lockdep.c:3431 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920 lock_sock_nested+0xc2/0x110 net/core/sock.c:2777 lock_sock include/net/sock.h:1463 [inline] do_ip_getsockopt+0x1b3/0x2170 net/ipv4/ip_sockglue.c:1329 ip_getsockopt+0x90/0x220 net/ipv4/ip_sockglue.c:1560 tcp_getsockopt+0x82/0xd0 net/ipv4/tcp.c:3359 sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2934 SYSC_getsockopt net/socket.c:1880 [inline] SyS_getsockopt+0x178/0x340 net/socket.c:1862 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x453de9 RSP: 002b:00007f470c7eec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007f470c7ef6d4 RCX: 0000000000453de9 RDX: 0000000000000029 RSI: 0000000000000000 RDI: 0000000000000015 RBP: 000000000072bea0 R08: 0000000020745000 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000000f2 R14: 00000000006f1750 R15: 0000000000000000 ipt_ECN: unsupported ECN operation 2 ipt_ECN: unsupported ECN operation 2 kauditd_printk_skb: 9 callbacks suppressed audit: type=1400 audit(1519465931.384:31): avc: denied { prog_run } for pid=6284 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=bpf permissive=1 audit: type=1400 audit(1519465931.415:32): avc: denied { map } for pid=6286 comm="syz-executor2" path=2F616E6F6E5F6875676570616765202864656C6574656429 dev="hugetlbfs" ino=15966 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:hugetlbfs_t:s0 tclass=file permissive=1 audit: type=1400 audit(1519465931.477:33): avc: denied { map } for pid=6301 comm="syz-executor4" path="/dev/binder0" dev="devtmpfs" ino=9536 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 netlink: 3 bytes leftover after parsing attributes in process `syz-executor5'. netlink: 3 bytes leftover after parsing attributes in process `syz-executor5'. netlink: 3 bytes leftover after parsing attributes in process `syz-executor5'. audit: type=1400 audit(1519465931.647:34): avc: denied { setuid } for pid=6375 comm="syz-executor0" capability=7 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 netlink: 3 bytes leftover after parsing attributes in process `syz-executor5'. devpts: called with bogus options devpts: called with bogus options