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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 ffff88803f6a63a8 by task syz-executor3/23542

CPU: 1 PID: 23542 Comm: syz-executor3 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:00007fc16147dc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc16147e6d4
R13: 00000000004c5194 R14: 00000000004d8a28 R15: 00000000ffffffff

Allocated by task 19941:
 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
 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x700 mm/slab.c:3554
 getname_flags fs/namei.c:140 [inline]
 getname_flags+0xd6/0x5b0 fs/namei.c:129
 getname fs/namei.c:211 [inline]
 user_path_create fs/namei.c:3693 [inline]
 do_symlinkat+0xde/0x2c0 fs/namei.c:4146
 __do_sys_symlink fs/namei.c:4172 [inline]
 __se_sys_symlink fs/namei.c:4170 [inline]
 __x64_sys_symlink+0x59/0x80 fs/namei.c:4170
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 19941:
 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]
 kmem_cache_free+0x86/0x260 mm/slab.c:3760
 putname+0xef/0x130 fs/namei.c:261
 filename_create+0x29d/0x5a0 fs/namei.c:3658
 user_path_create fs/namei.c:3693 [inline]
 do_symlinkat+0xf3/0x2c0 fs/namei.c:4146
 __do_sys_symlink fs/namei.c:4172 [inline]
 __se_sys_symlink fs/namei.c:4170 [inline]
 __x64_sys_symlink+0x59/0x80 fs/namei.c:4170
 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 ffff88803f6a63c0
 which belongs to the cache names_cache of size 4096
The buggy address is located 24 bytes to the left of
 4096-byte region [ffff88803f6a63c0, ffff88803f6a73c0)
The buggy address belongs to the page:
page:ffffea0000fda980 count:1 mapcount:0 mapping:ffff88812c2bec40 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea00020ca008 ffffea000166a488 ffff88812c2bec40
raw: 0000000000000000 ffff88803f6a63c0 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88803f6a6280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88803f6a6300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803f6a6380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                  ^
 ffff88803f6a6400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803f6a6480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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