audit: type=1400 audit(1519118447.377:8): avc: denied { map } for pid=4101 comm="syz-execprog" path="/root/syzkaller-shm754023049" 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-executor0/4109 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: 6 locks held by syz-executor0/4109: #0: (sb_writers#4){.+.+}, at: [<00000000d32dbed3>] sb_start_write include/linux/fs.h:1547 [inline] #0: (sb_writers#4){.+.+}, at: [<00000000d32dbed3>] mnt_want_write+0x3f/0xb0 fs/namespace.c:386 #1: (&type->i_mutex_dir_key/1){+.+.}, at: [<00000000c7b44eef>] inode_lock_nested include/linux/fs.h:748 [inline] #1: (&type->i_mutex_dir_key/1){+.+.}, at: [<00000000c7b44eef>] do_rmdir+0x380/0x5f0 fs/namei.c:3906 #2: (sb_internal){.+.+}, at: [<00000000e0df12a5>] sb_start_intwrite include/linux/fs.h:1594 [inline] #2: (sb_internal){.+.+}, at: [<00000000e0df12a5>] ext4_evict_inode+0x5e3/0x17d0 fs/ext4/inode.c:250 #3: ((&idev->mc_ifc_timer)){+.-.}, at: [<000000008de23c89>] lockdep_copy_map include/linux/lockdep.h:178 [inline] #3: ((&idev->mc_ifc_timer)){+.-.}, at: [<000000008de23c89>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316 #4: (rcu_read_lock){....}, at: [<000000001b46c3f8>] read_pnet include/net/net_namespace.h:280 [inline] #4: (rcu_read_lock){....}, at: [<000000001b46c3f8>] dev_net include/linux/netdevice.h:2056 [inline] #4: (rcu_read_lock){....}, at: [<000000001b46c3f8>] mld_sendpack+0x180/0xe70 net/ipv6/mcast.c:1625 #5: (rcu_read_lock){....}, at: [<0000000007e38dd3>] nf_hook.constprop.37+0x0/0x830 net/ipv6/mcast.c:2795 stack backtrace: CPU: 0 PID: 4109 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:arch_local_irq_restore arch/x86/include/asm/paravirt.h:777 [inline] RIP: 0010:kmem_cache_free+0xf2/0x2a0 mm/slab.c:3744 RSP: 0018:ffff8801befff2c8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff12 RAX: 0000000000000007 RBX: ffff8801d50eb800 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 1ffff10037b8ed65 RDI: 0000000000000282 RBP: ffff8801befff2e8 R08: 1ffff10037dffe27 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801b07d67c0 R13: 0000000000000282 R14: ffffffff81f0f2a2 R15: ffff8801bdc76240 jbd2_free_handle include/linux/jbd2.h:1426 [inline] jbd2_journal_stop+0x482/0x1490 fs/jbd2/transaction.c:1781 __ext4_journal_stop+0x12c/0x1c0 fs/ext4/ext4_jbd2.c:103 ext4_evict_inode+0xc2b/0x17d0 fs/ext4/inode.c:334 evict+0x481/0x920 fs/inode.c:553 iput_final fs/inode.c:1515 [inline] iput+0x7b9/0xaf0 fs/inode.c:1542 dentry_unlink_inode+0x4b0/0x5e0 fs/dcache.c:371 d_delete+0x1ca/0x280 fs/dcache.c:2393 vfs_rmdir+0x32d/0x410 fs/namei.c:3870 do_rmdir+0x4c8/0x5f0 fs/namei.c:3918 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:00007ffe1da37098 EFLAGS: 00000202 ORIG_RAX: 0000000000000054 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 0000000000453b37 RDX: 0000000000000000 RSI: 00007ffe1da38e50 RDI: 00007ffe1da38e50 RBP: 00007ffe1da38e50 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000027e1940 R13: 0000000000000000 R14: 0000000000000003 R15: 00000000027e0914