==================================================================
BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:982 [inline]
BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:560 [inline]
BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x9e5/0xa30 net/xfrm/xfrm_state.c:830
Write of size 8 at addr ffff888025b40030 by task syz.1.471/7563

CPU: 0 UID: 0 PID: 7563 Comm: syz.1.471 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 __hlist_del include/linux/list.h:982 [inline]
 hlist_del_rcu include/linux/rculist.h:560 [inline]
 __xfrm_state_delete+0x9e5/0xa30 net/xfrm/xfrm_state.c:830
 xfrm_state_delete net/xfrm/xfrm_state.c:856 [inline]
 xfrm_state_delete_tunnel net/xfrm/xfrm_state.c:3091 [inline]
 __xfrm_state_delete+0x85e/0xa30 net/xfrm/xfrm_state.c:837
 xfrm_state_delete net/xfrm/xfrm_state.c:856 [inline]
 xfrm_state_flush+0x512/0x700 net/xfrm/xfrm_state.c:939
 pfkey_flush+0x1bd/0x340 net/key/af_key.c:1769
 pfkey_process+0x6d9/0x840 net/key/af_key.c:2848
 pfkey_sendmsg+0x435/0x850 net/key/af_key.c:3699
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
 __sys_sendmsg+0x16d/0x220 net/socket.c:2700
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4bf0f8eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4bef1f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f4bf11e5fa0 RCX: 00007f4bf0f8eec9
RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007f4bf1011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4bf11e6038 R14: 00007f4bf11e5fa0 R15: 00007ffdf021afc8
 </TASK>

Allocated by task 7255:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:330 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:356
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4191 [inline]
 slab_alloc_node mm/slub.c:4240 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4247
 xfrm_state_alloc+0x23/0x5c0 net/xfrm/xfrm_state.c:733
 __find_acq_core+0xb59/0x2900 net/xfrm/xfrm_state.c:1833
 xfrm_find_acq+0x7b/0xa0 net/xfrm/xfrm_state.c:2353
 xfrm_alloc_userspi+0x58e/0xbb0 net/xfrm/xfrm_user.c:1863
 xfrm_user_rcv_msg+0x58b/0xc00 net/xfrm/xfrm_user.c:3501
 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552
 xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3523
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0xa98/0xc70 net/socket.c:2614
 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2668
 __sys_sendmsg+0x16d/0x220 net/socket.c:2700
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 9:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:243 [inline]
 __kasan_slab_free+0x60/0x70 mm/kasan/common.c:275
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2422 [inline]
 slab_free mm/slub.c:4695 [inline]
 kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4797
 xfrm_state_free net/xfrm/xfrm_state.c:591 [inline]
 xfrm_state_gc_destroy net/xfrm/xfrm_state.c:618 [inline]
 xfrm_state_gc_task+0x50a/0x770 net/xfrm/xfrm_state.c:634
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:463
 ret_from_fork+0x56a/0x730 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888025b40000
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff888025b40000, ffff888025b403a0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888025b40440 pfn:0x25b40
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff8881032bc3c0 dead000000000122 0000000000000000
raw: ffff888025b40440 00000000801e001d 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff8881032bc3c0 dead000000000122 0000000000000000
head: ffff888025b40440 00000000801e001d 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea000096d001 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 7255, tgid 7254 (syz.1.376), ts 81233245978, free_ts 81210461309
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2492 [inline]
 allocate_slab mm/slub.c:2660 [inline]
 new_slab+0x247/0x330 mm/slub.c:2714
 ___slab_alloc+0xcf2/0x1750 mm/slub.c:3901
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3992
 __slab_alloc_node mm/slub.c:4067 [inline]
 slab_alloc_node mm/slub.c:4228 [inline]
 kmem_cache_alloc_noprof+0xef/0x3b0 mm/slub.c:4247
 xfrm_state_alloc+0x23/0x5c0 net/xfrm/xfrm_state.c:733
 __find_acq_core+0xb59/0x2900 net/xfrm/xfrm_state.c:1833
 xfrm_find_acq+0x7b/0xa0 net/xfrm/xfrm_state.c:2353
 xfrm_alloc_userspi+0x58e/0xbb0 net/xfrm/xfrm_user.c:1863
 xfrm_user_rcv_msg+0x58b/0xc00 net/xfrm/xfrm_user.c:3501
 netlink_rcv_skb+0x155/0x420 net/netlink/af_netlink.c:2552
 xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3523
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346
page last free pid 7253 tgid 7252 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895
 __folio_put+0x329/0x450 mm/swap.c:112
 folio_put include/linux/mm.h:1360 [inline]
 put_page include/linux/mm.h:1429 [inline]
 put_netmem net/core/skbuff.c:7370 [inline]
 skb_page_unref include/linux/skbuff_ref.h:43 [inline]
 __skb_frag_unref include/linux/skbuff_ref.h:56 [inline]
 skb_frag_unref include/linux/skbuff_ref.h:71 [inline]
 ___pskb_trim+0xc5f/0x1410 net/core/skbuff.c:2696
 __pskb_trim include/linux/skbuff.h:3278 [inline]
 pskb_trim_rcsum_slow+0x19e/0x470 net/core/skbuff.c:2767
 pskb_trim_rcsum include/linux/skbuff.h:4061 [inline]
 ip6_rcv_core+0x1780/0x1c30 net/ipv6/ip6_input.c:275
 ipv6_rcv+0x7b/0x650 net/ipv6/ip6_input.c:308
 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5991
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6104
 netif_receive_skb_internal net/core/dev.c:6190 [inline]
 netif_receive_skb+0x137/0x7b0 net/core/dev.c:6249
 tun_rx_batched.isra.0+0x3ee/0x740 drivers/net/tun.c:1509
 tun_get_user+0x28e4/0x3ce0 drivers/net/tun.c:1950
 tun_chr_write_iter+0xdc/0x210 drivers/net/tun.c:1996
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x7d3/0x11d0 fs/read_write.c:686
 ksys_write+0x12a/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888025b3ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888025b3ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888025b40000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888025b40080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888025b40100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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