audit: type=1400 audit(1519113947.864:8): avc: denied { map } for pid=4170 comm="syz-execprog" path="/root/syzkaller-shm743089636" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1 IPVS: ftp: loaded support on port[0] = 21 IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready ===================================== WARNING: bad unlock balance detected! 4.16.0-rc1+ #232 Not tainted ------------------------------------- syz-executor0/4178 is trying to release lock (rcu_read_lock_bh) at: [] rcu_read_unlock_bh include/linux/rcupdate.h:722 [inline] [] hashlimit_mt_common.isra.10+0x1beb/0x2610 net/netfilter/xt_hashlimit.c:777 but there are no more locks to release! other info that might help us debug this: 3 locks held by syz-executor0/4178: #0: ((&idev->mc_ifc_timer)){+.-.}, at: [<00000000f05bd828>] lockdep_copy_map include/linux/lockdep.h:178 [inline] #0: ((&idev->mc_ifc_timer)){+.-.}, at: [<00000000f05bd828>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316 #1: (rcu_read_lock){....}, at: [<0000000095ada7a8>] read_pnet include/net/net_namespace.h:280 [inline] #1: (rcu_read_lock){....}, at: [<0000000095ada7a8>] dev_net include/linux/netdevice.h:2056 [inline] #1: (rcu_read_lock){....}, at: [<0000000095ada7a8>] mld_sendpack+0x180/0xe70 net/ipv6/mcast.c:1625 #2: (rcu_read_lock){....}, at: [<00000000f23a3bb0>] nf_hook.constprop.37+0x0/0x830 net/ipv6/mcast.c:2795 stack backtrace: CPU: 1 PID: 4178 Comm: syz-executor0 Not tainted 4.16.0-rc1+ #232 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_unlock_imbalance_bug+0x12f/0x140 kernel/locking/lockdep.c:3484 __lock_release kernel/locking/lockdep.c:3691 [inline] lock_release+0x6fe/0xa40 kernel/locking/lockdep.c:3939 rcu_lock_release include/linux/rcupdate.h:249 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:724 [inline] hashlimit_mt_common.isra.10+0x1c08/0x2610 net/netfilter/xt_hashlimit.c:777 hashlimit_mt+0x78/0x90 net/netfilter/xt_hashlimit.c:846 ip6t_do_table+0x98d/0x1a30 net/ipv6/netfilter/ip6_tables.c:319 ip6table_raw_hook+0x65/0x80 net/ipv6/netfilter/ip6table_raw.c:42 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0xba/0x1a0 net/netfilter/core.c:483 nf_hook.constprop.37+0x3f6/0x830 include/linux/netfilter.h:243 NF_HOOK include/linux/netfilter.h:286 [inline] mld_sendpack+0x6c2/0xe70 net/ipv6/mcast.c:1658 mld_send_cr net/ipv6/mcast.c:1954 [inline] mld_ifc_timer_expire+0x3d9/0x770 net/ipv6/mcast.c:2451 call_timer_fn+0x228/0x820 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:541 [inline] smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:829 RIP: 0010:lock_is_held_type+0x197/0x210 kernel/locking/lockdep.c:3963 RSP: 0018:ffff8801af7cfaf0 EFLAGS: 00000296 ORIG_RAX: ffffffffffffff12 RAX: 0000000000000000 RBX: 0000000000000282 RCX: ffffffff81b85edc RDX: 1ffffffff0d592cd RSI: 00000000ffffffff RDI: 0000000000000282 RBP: ffff8801af7cfb08 R08: 0000000000000000 R09: 1ffff10035ef9f70 R10: ffff8801af7cfa10 R11: 0000000000000000 R12: ffff8801aec12200 R13: 0000000000000000 R14: 000000000000031a R15: ffff8801b9ac32c0 lock_is_held include/linux/lockdep.h:344 [inline] rcu_preempt_sleep_check include/linux/rcupdate.h:301 [inline] ___might_sleep+0x35e/0x470 kernel/sched/core.c:6093 __might_sleep+0x95/0x190 kernel/sched/core.c:6081 dput.part.21+0x8f/0x830 fs/dcache.c:794 dput+0x1f/0x30 fs/dcache.c:790 path_put fs/namei.c:481 [inline] do_rmdir+0x1bd/0x5f0 fs/namei.c:3925 SYSC_rmdir fs/namei.c:3936 [inline] SyS_rmdir+0x1a/0x20 fs/namei.c:3934 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x453b37 RSP: 002b:00007ffd67041918 EFLAGS: 00000206 ORIG_RAX: 0000000000000054 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 0000000000453b37 RDX: 0000000000000000 RSI: 00007ffd670436d0 RDI: 00007ffd670436d0 RBP: 00007ffd670436d0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000001a0b940 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000001a0a914