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BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:704 [inline]
BUG: KASAN: use-after-free in hlist_del_rcu include/linux/rculist.h:455 [inline]
BUG: KASAN: use-after-free in __xfrm_policy_unlink+0x9ec/0xa00 net/xfrm/xfrm_policy.c:2212
Write of size 8 at addr ffff88808bff2d90 by task syz-executor356/8490

CPU: 0 PID: 8490 Comm: syz-executor356 Not tainted 4.20.0+ #14
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:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/generic_report.c:140
 __hlist_del include/linux/list.h:704 [inline]
 hlist_del_rcu include/linux/rculist.h:455 [inline]
 __xfrm_policy_unlink+0x9ec/0xa00 net/xfrm/xfrm_policy.c:2212
 xfrm_policy_insert+0x223/0x910 net/xfrm/xfrm_policy.c:1587
 pfkey_spdadd+0x111a/0x19a0 net/key/af_key.c:2339
 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: 0033:0x442099
Code: e8 7c e7 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 db 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffcc38cd908 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000442099
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000002124 R09: 0000000000002124
R10: 0000000000002124 R11: 0000000000000246 R12: 000000000000005a
R13: 000000000000cd58 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 8484:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 kasan_kmalloc mm/kasan/common.c:482 [inline]
 kasan_kmalloc+0xcf/0xe0 mm/kasan/common.c:455
 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3607
 kmalloc include/linux/slab.h:545 [inline]
 kzalloc include/linux/slab.h:740 [inline]
 xfrm_policy_alloc+0xfb/0x530 net/xfrm/xfrm_policy.c:383
 pfkey_spdadd+0x24d/0x19a0 net/key/af_key.c:2272
 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

Freed by task 16:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:444
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:452
 __cache_free mm/slab.c:3485 [inline]
 kfree+0xcf/0x230 mm/slab.c:3804
 xfrm_policy_destroy_rcu+0x48/0x60 net/xfrm/xfrm_policy.c:407
 __rcu_reclaim kernel/rcu/rcu.h:240 [inline]
 rcu_do_batch kernel/rcu/tree.c:2452 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline]
 rcu_process_callbacks+0xc4a/0x1680 kernel/rcu/tree.c:2754
 __do_softirq+0x30b/0xb11 kernel/softirq.c:292

The buggy address belongs to the object at ffff88808bff2d80
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 16 bytes inside of
 1024-byte region [ffff88808bff2d80, ffff88808bff3180)
The buggy address belongs to the page:
page:ffffea00022ffc80 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea00022f7008 ffffea000238f108 ffff88812c3f0ac0
raw: 0000000000000000 ffff88808bff2000 0000000100000007 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808bff2c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808bff2d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88808bff2d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88808bff2e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808bff2e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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