audit: type=1400 audit(1519111509.499:8): avc: denied { map } for pid=4168 comm="syz-execprog" path="/root/syzkaller-shm436274392" 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-executor0/4177 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-executor0/4177: #0: ((&idev->mc_ifc_timer)){+.-.}, at: [<00000000c908501e>] lockdep_copy_map include/linux/lockdep.h:178 [inline] #0: ((&idev->mc_ifc_timer)){+.-.}, at: [<00000000c908501e>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316 #1: (rcu_read_lock){....}, at: [<00000000d61b63e8>] read_pnet include/net/net_namespace.h:280 [inline] #1: (rcu_read_lock){....}, at: [<00000000d61b63e8>] dev_net include/linux/netdevice.h:2050 [inline] #1: (rcu_read_lock){....}, at: [<00000000d61b63e8>] mld_sendpack+0x180/0xe70 net/ipv6/mcast.c:1625 #2: (rcu_read_lock){....}, at: [<00000000caaf6436>] nf_hook.constprop.37+0x0/0x830 net/ipv6/mcast.c:2795 stack backtrace: CPU: 0 PID: 4177 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:percpu_counter_add_batch+0x49/0x130 lib/percpu_counter.c:88 RSP: 0018:ffff8801b245f7e8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff12 RAX: 000000000002fd04 RBX: ffff8801ae3fcc80 RCX: ffffffff8264893f RDX: 1ffffffff0d424c2 RSI: 0000000000000001 RDI: ffffffff86a125c0 RBP: ffff8801b245f818 R08: 000000000000000b R09: ffff8801b245f540 R10: 000000007686e333 R11: 000000009c8fbb98 R12: 0000000000000001 R13: ffffffff86a12610 R14: 0000000000000020 R15: ffffffff86a125c0 percpu_counter_add include/linux/percpu_counter.h:55 [inline] percpu_counter_inc include/linux/percpu_counter.h:179 [inline] get_empty_filp+0x154/0x4f0 fs/file_table.c:126 path_openat+0xed/0x3530 fs/namei.c:3495 do_filp_open+0x25b/0x3b0 fs/namei.c:3553 do_sys_open+0x502/0x6d0 fs/open.c:1059 SYSC_open fs/open.c:1077 [inline] SyS_open+0x2d/0x40 fs/open.c:1072 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x451f10 RSP: 002b:00007ffc05a75520 EFLAGS: 00000202 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000000001d RCX: 0000000000451f10 RDX: 000000000000000c RSI: 0000000000090800 RDI: 00007ffc05a77380 RBP: 00007ffc05a77380 R08: 0000000000000001 R09: 0000000000d92940 R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000009d R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000d92914