audit: type=1400 audit(1519083588.194:8): avc: denied { map } for pid=4151 comm="syz-execprog" path="/root/syzkaller-shm289719666" 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-executor0/4300 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-executor0/4300: #0: ((&idev->mc_dad_timer)){+.-.}, at: [<00000000c5f05dd6>] lockdep_copy_map include/linux/lockdep.h:178 [inline] #0: ((&idev->mc_dad_timer)){+.-.}, at: [<00000000c5f05dd6>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316 #1: (rcu_read_lock){....}, at: [<00000000852b6915>] read_pnet include/net/net_namespace.h:280 [inline] #1: (rcu_read_lock){....}, at: [<00000000852b6915>] dev_net include/linux/netdevice.h:2056 [inline] #1: (rcu_read_lock){....}, at: [<00000000852b6915>] mld_sendpack+0x180/0xe70 net/ipv6/mcast.c:1625 #2: (rcu_read_lock){....}, at: [<000000005ae80585>] nf_hook.constprop.37+0x0/0x830 net/ipv6/mcast.c:2795 stack backtrace: CPU: 1 PID: 4300 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_initial_cr.part.25+0x103/0x150 net/ipv6/mcast.c:2075 mld_send_initial_cr net/ipv6/mcast.c:2059 [inline] mld_dad_timer_expire+0x31/0x100 net/ipv6/mcast.c:2093 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:arch_local_irq_restore arch/x86/include/asm/paravirt.h:777 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x5e/0xba kernel/locking/spinlock.c:184 RSP: 0018:ffff8801b2595f50 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff12 RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 0000000000000000 RDX: 1ffffffff0d592cd RSI: 0000000000000001 RDI: 0000000000000282 RBP: ffff8801b2595f60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff881bdb88 R13: ffff8801b2596118 R14: 0000000000000000 R15: dffffc0000000000 __debug_check_no_obj_freed lib/debugobjects.c:758 [inline] debug_check_no_obj_freed+0x3da/0xf1f lib/debugobjects.c:774 free_pages_prepare mm/page_alloc.c:1065 [inline] __free_pages_ok+0x765/0x31e0 mm/page_alloc.c:1260 free_compound_page+0x5c/0x70 mm/page_alloc.c:601 free_transhuge_page+0x2d2/0x430 mm/huge_memory.c:2732 __put_compound_page+0x88/0xc0 mm/swap.c:95 release_pages+0x64b/0x1230 mm/swap.c:788 free_pages_and_swap_cache+0x2ad/0x400 mm/swap_state.c:322 tlb_flush_mmu_free+0xb4/0x160 mm/memory.c:259 zap_pte_range mm/memory.c:1404 [inline] zap_pmd_range mm/memory.c:1441 [inline] zap_pud_range mm/memory.c:1470 [inline] zap_p4d_range mm/memory.c:1491 [inline] unmap_page_range+0x181e/0x22e0 mm/memory.c:1512 unmap_single_vma+0x15f/0x2d0 mm/memory.c:1557 unmap_vmas+0xf1/0x1b0 mm/memory.c:1587 exit_mmap+0x23a/0x500 mm/mmap.c:3020 __mmput kernel/fork.c:971 [inline] mmput+0x223/0x6c0 kernel/fork.c:992 exit_mm kernel/exit.c:544 [inline] do_exit+0x90a/0x1ad0 kernel/exit.c:852 do_group_exit+0x149/0x400 kernel/exit.c:968 SYSC_exit_group kernel/exit.c:979 [inline] SyS_exit_group+0x1d/0x20 kernel/exit.c:977 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x453da9 RSP: 002b:00007fff341f1088 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000000f RCX: 0000000000453da9 RDX: 00000000000004d5 RSI: 0000000000735638 RDI: 0000000000000000 RBP: 00007fff341f1760 R08: 0000000000000000 R09: 0000000000000003 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000001380