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BUG: KASAN: slab-out-of-bounds in __write_once_size include/linux/compiler.h:218 [inline]
BUG: KASAN: slab-out-of-bounds in __hlist_del include/linux/list.h:702 [inline]
BUG: KASAN: slab-out-of-bounds in hlist_del_init include/linux/list.h:717 [inline]
BUG: KASAN: slab-out-of-bounds in __xfrm_policy_unlink+0x977/0xa00 net/xfrm/xfrm_policy.c:2213
Write of size 8 at addr ffff8880910035e8 by task syz-executor2/30623

CPU: 1 PID: 30623 Comm: syz-executor2 Not tainted 4.20.0+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1db/0x2d0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:438
 __write_once_size include/linux/compiler.h:218 [inline]
 __hlist_del include/linux/list.h:702 [inline]
 hlist_del_init include/linux/list.h:717 [inline]
 __xfrm_policy_unlink+0x977/0xa00 net/xfrm/xfrm_policy.c:2213
 xfrm_policy_flush+0x331/0x460 net/xfrm/xfrm_policy.c:1789
 pfkey_spdflush+0xaf/0x3c0 net/key/af_key.c:2785
 pfkey_process+0x6d2/0x810 net/key/af_key.c:2844
 pfkey_sendmsg+0x5bb/0xfc0 net/key/af_key.c:3683
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x7ec/0x910 net/socket.c:2116
 __sys_sendmsg+0x112/0x270 net/socket.c:2154
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg net/socket.c:2161 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457ec9
Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1390148c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000004
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f13901496d4
R13: 00000000004c5194 R14: 00000000004d8a28 R15: 00000000ffffffff

Allocated by task 21230:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc mm/kasan/kasan.c:553 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531
 kmem_cache_alloc_trace+0x152/0x760 mm/slab.c:3620
 kmalloc include/linux/slab.h:546 [inline]
 kzalloc include/linux/slab.h:741 [inline]
 ipv6_add_dev net/ipv6/addrconf.c:376 [inline]
 ipv6_add_dev+0x189/0x12c0 net/ipv6/addrconf.c:366
 addrconf_notify+0xa12/0x25f0 net/ipv6/addrconf.c:3452
 notifier_call_chain+0x179/0x380 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
 call_netdevice_notifiers net/core/dev.c:1765 [inline]
 register_netdevice+0xae0/0x10b0 net/core/dev.c:8658
 veth_newlink+0x47b/0xa60 drivers/net/veth.c:1271
 __rtnl_newlink+0x1281/0x1a70 net/core/rtnetlink.c:3182
 rtnl_newlink+0x69/0xa0 net/core/rtnetlink.c:3240
 rtnetlink_rcv_msg+0x481/0xc30 net/core/rtnetlink.c:5125
 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5143
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 __sys_sendto+0x387/0x5f0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto net/socket.c:1796 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 19437:
 save_stack+0x45/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xcf/0x230 mm/slab.c:3817
 skb_free_head+0x93/0xb0 net/core/skbuff.c:553
 skb_release_data+0x6ea/0x970 net/core/skbuff.c:573
 skb_release_all+0x4d/0x60 net/core/skbuff.c:627
 __kfree_skb net/core/skbuff.c:641 [inline]
 kfree_skb net/core/skbuff.c:659 [inline]
 kfree_skb+0x199/0x580 net/core/skbuff.c:653
 vti_xmit net/ipv4/ip_vti.c:232 [inline]
 vti_tunnel_xmit+0x891/0x1730 net/ipv4/ip_vti.c:264
 __netdev_start_xmit include/linux/netdevice.h:4382 [inline]
 netdev_start_xmit include/linux/netdevice.h:4391 [inline]
 xmit_one net/core/dev.c:3278 [inline]
 dev_hard_start_xmit+0x261/0xc70 net/core/dev.c:3294
 __dev_queue_xmit+0x2f8a/0x3a60 net/core/dev.c:3864
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3897
 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1511
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0xc56/0x28e0 net/ipv6/ip6_output.c:120
 ip6_finish_output+0x577/0xc30 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x23c/0xa00 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:444 [inline]
 ip6_local_out+0xc4/0x1b0 net/ipv6/output_core.c:176
 ip6_send_skb+0xbb/0x350 net/ipv6/ip6_output.c:1727
 udp_v6_send_skb.isra.0+0x834/0x14b0 net/ipv6/udp.c:1169
 udpv6_sendmsg+0x2baa/0x3550 net/ipv6/udp.c:1466
 inet_sendmsg+0x1af/0x740 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 ___sys_sendmsg+0x409/0x910 net/socket.c:2116
 __sys_sendmmsg+0x246/0x6f0 net/socket.c:2211
 __do_sys_sendmmsg net/socket.c:2240 [inline]
 __se_sys_sendmmsg net/socket.c:2237 [inline]
 __x64_sys_sendmmsg+0x9d/0x100 net/socket.c:2237
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff888091003240
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 936 bytes inside of
 1024-byte region [ffff888091003240, ffff888091003640)
The buggy address belongs to the page:
page:ffffea0002440080 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0xffff888091003b40 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea00027bc788 ffffea0002147608 ffff88812c3f0ac0
raw: ffff888091003b40 ffff888091002040 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888091003480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888091003500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888091003580: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                          ^
 ffff888091003600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888091003680: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
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