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BUG: KASAN: use-after-free in __write_once_size include/linux/compiler.h:247 [inline]
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:632 [inline]
BUG: KASAN: use-after-free in hlist_del_rcu include/linux/rculist.h:340 [inline]
BUG: KASAN: use-after-free in nf_nat_cleanup_conntrack+0x1ca/0x1e0 net/netfilter/nf_nat_core.c:691
Write of size 8 at addr ffff8801c0b5df58 by task udevd/5387

CPU: 0 PID: 5387 Comm: udevd Not tainted 4.4.174+ #4
 0000000000000000 24c6a0a4ffebc233 ffff8801db607a10 ffffffff81aad1a1
 0000000000000001 ffffea000702d740 ffff8801c0b5df58 0000000000000008
 ffffffff82361100 ffff8801db607a48 ffffffff81490120 0000000000000001
Call Trace:
 <IRQ>  [<ffffffff81aad1a1>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ>  [<ffffffff81aad1a1>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff81490120>] print_address_description+0x6f/0x21b mm/kasan/report.c:252
 [<ffffffff81490358>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff81490358>] kasan_report mm/kasan/report.c:408 [inline]
 [<ffffffff81490358>] kasan_report.cold+0x8c/0x2be mm/kasan/report.c:393
 [<ffffffff81484f77>] __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:434
 [<ffffffff823612ca>] __write_once_size include/linux/compiler.h:247 [inline]
 [<ffffffff823612ca>] __hlist_del include/linux/list.h:632 [inline]
 [<ffffffff823612ca>] hlist_del_rcu include/linux/rculist.h:340 [inline]
 [<ffffffff823612ca>] nf_nat_cleanup_conntrack+0x1ca/0x1e0 net/netfilter/nf_nat_core.c:691
 [<ffffffff8232d7b0>] __nf_ct_ext_destroy+0x140/0x2a0 net/netfilter/nf_conntrack_extend.c:40
 [<ffffffff8230e217>] nf_ct_ext_destroy include/net/netfilter/nf_conntrack_extend.h:80 [inline]
 [<ffffffff8230e217>] nf_conntrack_free+0x77/0x120 net/netfilter/nf_conntrack_core.c:904
 [<ffffffff823116f0>] destroy_conntrack+0x270/0x380 net/netfilter/nf_conntrack_core.c:365
 [<ffffffff822f6cd9>] nf_conntrack_destroy+0x99/0x1a0 net/netfilter/core.c:389
 [<ffffffff821eff3a>] nf_conntrack_put include/linux/skbuff.h:3377 [inline]
 [<ffffffff821eff3a>] skb_release_head_state+0x15a/0x210 net/core/skbuff.c:649
 [<ffffffff821fd0e6>] skb_release_all+0x16/0x60 net/core/skbuff.c:659
 [<ffffffff821fd257>] __kfree_skb net/core/skbuff.c:675 [inline]
 [<ffffffff821fd257>] kfree_skb+0xf7/0x400 net/core/skbuff.c:696
 [<ffffffff823b8e9a>] inet_frag_rbtree_purge+0xaa/0xf0 net/ipv4/ip_fragment.c:761
 [<ffffffff824e152f>] inet_frag_destroy+0x21f/0x2c0 net/ipv4/inet_fragment.c:156
 [<ffffffff823b8f14>] inet_frag_put include/net/inet_frag.h:124 [inline]
 [<ffffffff823b8f14>] ipq_put+0x34/0x40 net/ipv4/ip_fragment.c:164
 [<ffffffff823b954d>] ip_expire+0x14d/0x880 net/ipv4/ip_fragment.c:265
 [<ffffffff812582dd>] call_timer_fn+0x18d/0x850 kernel/time/timer.c:1185
 [<ffffffff81258ebf>] __run_timers kernel/time/timer.c:1261 [inline]
 [<ffffffff81258ebf>] run_timer_softirq+0x51f/0xb70 kernel/time/timer.c:1444
 [<ffffffff8271bb16>] __do_softirq+0x226/0xa3f kernel/softirq.c:273
 [<ffffffff810e1a8a>] invoke_softirq kernel/softirq.c:350 [inline]
 [<ffffffff810e1a8a>] irq_exit+0x10a/0x150 kernel/softirq.c:391
 [<ffffffff8271b24e>] exiting_irq arch/x86/include/asm/apic.h:652 [inline]
 [<ffffffff8271b24e>] smp_apic_timer_interrupt+0x7e/0xb0 arch/x86/kernel/apic/apic.c:926
 [<ffffffff8271a59d>] apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:768
 <EOI>  [<ffffffff8271802f>] ? arch_local_irq_restore arch/x86/include/asm/paravirt.h:812 [inline]
 <EOI>  [<ffffffff8271802f>] ? __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:162 [inline]
 <EOI>  [<ffffffff8271802f>] ? _raw_spin_unlock_irqrestore+0x5f/0x70 kernel/locking/spinlock.c:191
 [<ffffffff8195365c>] spin_unlock_irqrestore include/linux/spinlock.h:362 [inline]
 [<ffffffff8195365c>] avc_reclaim_node security/selinux/avc.c:541 [inline]
 [<ffffffff8195365c>] avc_alloc_node security/selinux/avc.c:559 [inline]
 [<ffffffff8195365c>] avc_alloc_node+0x31c/0x3c0 security/selinux/avc.c:547
 [<ffffffff81954992>] avc_insert security/selinux/avc.c:670 [inline]
 [<ffffffff81954992>] avc_compute_av+0x182/0x610 security/selinux/avc.c:976
 [<ffffffff81956a8e>] avc_has_perm_noaudit security/selinux/avc.c:1112 [inline]
 [<ffffffff81956a8e>] avc_has_perm_flags+0x35e/0x3b0 security/selinux/avc.c:1161
 [<ffffffff81967a2c>] selinux_inode_follow_link+0x1bc/0x260 security/selinux/hooks.c:2850
 [<ffffffff8194d46a>] security_inode_follow_link+0xca/0x110 security/security.c:593
 [<ffffffff814be343>] get_link fs/namei.c:1059 [inline]
 [<ffffffff814be343>] trailing_symlink+0x183/0xad0 fs/namei.c:2168
 [<ffffffff814c56f7>] path_openat+0xc87/0x4470 fs/namei.c:3408
 [<ffffffff814ccab1>] do_filp_open+0x1a1/0x270 fs/namei.c:3440
 [<ffffffff814a7c8c>] do_open_execat+0x10c/0x6e0 fs/exec.c:805
 [<ffffffff814a8297>] open_exec+0x37/0x70 fs/exec.c:837
 [<ffffffff815a2b69>] load_elf_binary+0x789/0x4b80 fs/binfmt_elf.c:755
 [<ffffffff814aba1f>] search_binary_handler fs/exec.c:1475 [inline]
 [<ffffffff814aba1f>] search_binary_handler+0x14f/0x700 fs/exec.c:1453
 [<ffffffff814adc17>] exec_binprm fs/exec.c:1517 [inline]
 [<ffffffff814adc17>] do_execveat_common.isra.0+0x1007/0x1e90 fs/exec.c:1639
 [<ffffffff814af422>] do_execve fs/exec.c:1683 [inline]
 [<ffffffff814af422>] SYSC_execve fs/exec.c:1764 [inline]
 [<ffffffff814af422>] SyS_execve+0x42/0x50 fs/exec.c:1759
 [<ffffffff82718ef5>] stub_execve+0x5/0x5 arch/x86/entry/entry_64.S:440

The buggy address belongs to the page:
page:ffffea000702d740 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c0b5de00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8801c0b5de80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8801c0b5df00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                    ^
 ffff8801c0b5df80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8801c0b5e000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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