audit: type=1400 audit(1519108361.287:8): avc: denied { map } for pid=4112 comm="syz-execprog" path="/root/syzkaller-shm612365918" 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-rc2+ #320 Not tainted ------------------------------------- syz-executor0/4120 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-executor0/4120: #0: ((&idev->mc_ifc_timer)){+.-.}, at: [<00000000e1876ce8>] lockdep_copy_map include/linux/lockdep.h:178 [inline] #0: ((&idev->mc_ifc_timer)){+.-.}, at: [<00000000e1876ce8>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316 #1: (rcu_read_lock){....}, at: [<00000000c55beb3f>] read_pnet include/net/net_namespace.h:280 [inline] #1: (rcu_read_lock){....}, at: [<00000000c55beb3f>] dev_net include/linux/netdevice.h:2050 [inline] #1: (rcu_read_lock){....}, at: [<00000000c55beb3f>] mld_sendpack+0x180/0xe70 net/ipv6/mcast.c:1625 #2: (rcu_read_lock){....}, at: [<000000007ad3646d>] nf_hook.constprop.37+0x0/0x830 net/ipv6/mcast.c:2795 stack backtrace: CPU: 1 PID: 4120 Comm: syz-executor0 Not tainted 4.16.0-rc2+ #320 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+0x8e/0xa0 arch/x86/entry/entry_64.S:796 RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:787 [inline] RIP: 0010:__raw_write_unlock_irq include/linux/rwlock_api_smp.h:267 [inline] RIP: 0010:_raw_write_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:336 RSP: 0018:ffff8801bd1d73b8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff12 RAX: dffffc0000000000 RBX: ffffffff86a090c0 RCX: 0000000000000000 RDX: 1ffffffff0d592d7 RSI: 0000000000000001 RDI: ffffffff86ac96b8 RBP: ffff8801bd1d73c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801b9d6abd8 R13: dffffc0000000000 R14: ffff8801b9d6a640 R15: ffff8801b9d6a640 release_task+0xe9e/0x1a40 kernel/exit.c:220 wait_task_zombie kernel/exit.c:1161 [inline] wait_consider_task+0x2a10/0x3420 kernel/exit.c:1388 do_wait_thread kernel/exit.c:1451 [inline] do_wait+0x427/0xa70 kernel/exit.c:1522 kernel_wait4+0x1f5/0x370 kernel/exit.c:1665 SYSC_wait4+0x134/0x140 kernel/exit.c:1677 SyS_wait4+0x2c/0x40 kernel/exit.c:1673 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x40e0ea RSP: 002b:00007ffc43616db8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000040e0ea RDX: 0000000040000001 RSI: 00007ffc43616de4 RDI: ffffffffffffffff RBP: 00007ffc43617470 R08: 0000000000000001 R09: 0000000002939940 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000084 R13: 0000000000000000 R14: 0000000000000003 R15: 0000000002939914