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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 ffff8880a4297a28 by task syz-executor3/16852

CPU: 1 PID: 16852 Comm: syz-executor3 Not tainted 5.0.0-rc2+ #8
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
 __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
 xfrm_flush_policy+0x166/0x470 net/xfrm/xfrm_user.c:2129
 xfrm_user_rcv_msg+0x458/0x8d0 net/xfrm/xfrm_user.c:2663
 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477
 xfrm_netlink_rcv+0x70/0x90 net/xfrm/xfrm_user.c:2671
 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_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: 0033:0x458099
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:00007f64f609fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458099
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000004
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f64f60a06d4
R13: 00000000004c562b R14: 00000000004d9298 R15: 00000000ffffffff

Allocated by task 0:
(stack is not available)

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8880a4297a00
 which belongs to the cache cred_jar(97:syz5) of size 184
The buggy address is located 40 bytes inside of
 184-byte region [ffff8880a4297a00, ffff8880a4297ab8)
The buggy address belongs to the page:
page:ffffea000290a5c0 count:1 mapcount:0 mapping:ffff888095123300 index:0xffff8880a4297c00
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea000281f008 ffffea0002a234c8 ffff888095123300
raw: ffff8880a4297c00 ffff8880a4297000 0000000100000002 ffff8880681d2b40
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff8880681d2b40

Memory state around the buggy address:
 ffff8880a4297900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a4297980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880a4297a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff8880a4297a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a4297b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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