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BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:796 [inline]
BUG: KASAN: use-after-free in enqueue_timer kernel/time/timer.c:541 [inline]
BUG: KASAN: use-after-free in __internal_add_timer+0x2a6/0x4a0 kernel/time/timer.c:554
Write of size 8 at addr ffff8881c282b1c8 by task kworker/0:19/1847

CPU: 0 PID: 1847 Comm: kworker/0:19 Not tainted 5.4.219-syzkaller-00012-ga8aad8851131 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x630 mm/kasan/report.c:384
 __kasan_report+0xf6/0x130 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 hlist_add_head include/linux/list.h:796 [inline]
 enqueue_timer kernel/time/timer.c:541 [inline]
 __internal_add_timer+0x2a6/0x4a0 kernel/time/timer.c:554
 internal_add_timer kernel/time/timer.c:604 [inline]
 __mod_timer+0xaad/0x1c90 kernel/time/timer.c:1065
 mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
 wg_timers_any_authenticated_packet_traversal+0x125/0x180 drivers/net/wireguard/timers.c:215
 wg_packet_create_data_done drivers/net/wireguard/send.c:247 [inline]
 wg_packet_tx_worker+0x15d/0x4d0 drivers/net/wireguard/send.c:276
 process_one_work+0x6ca/0xc40 kernel/workqueue.c:2287
 worker_thread+0xae0/0x1440 kernel/workqueue.c:2433
 kthread+0x2d8/0x360 kernel/kthread.c:288
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354

The buggy address belongs to the page:
page:ffffea00070a0ac0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x102cc0(GFP_USER|__GFP_NOWARN)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x194/0x380 mm/page_alloc.c:2171
 get_page_from_freelist+0x524/0x560 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x372/0x860 mm/page_alloc.c:4891
 __alloc_pages include/linux/gfp.h:503 [inline]
 __alloc_pages_node include/linux/gfp.h:516 [inline]
 alloc_pages_node include/linux/gfp.h:530 [inline]
 stack_depot_save+0x3d1/0x470 lib/stackdepot.c:267
 save_stack mm/kasan/common.c:72 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x1a5/0x1e0 mm/kasan/common.c:529
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xd0/0x210 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 __alloc_skb+0x78/0x4d0 net/core/skbuff.c:198
 alloc_skb include/linux/skbuff.h:1060 [inline]
 nlmsg_new include/net/netlink.h:888 [inline]
 rtmsg_ifinfo_build_skb+0x81/0x180 net/core/rtnetlink.c:3503
 rollback_registered_many+0xd78/0x1370 net/core/dev.c:8621
 rollback_registered net/core/dev.c:8659 [inline]
 unregister_netdevice_queue+0x333/0x500 net/core/dev.c:9755
 unregister_netdevice include/linux/netdevice.h:2725 [inline]
 __tun_detach+0xfe5/0x1af0 drivers/net/tun.c:740
 tun_detach drivers/net/tun.c:757 [inline]
 tun_chr_close+0x8e/0xd0 drivers/net/tun.c:3534
 __fput+0x261/0x680 fs/file_table.c:281
 task_work_run+0x186/0x1b0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xce6/0x2d30 kernel/exit.c:812
 do_group_exit+0x136/0x300 kernel/exit.c:910
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x7fe/0x930 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4953 [inline]
 __free_pages+0x8f/0x250 mm/page_alloc.c:4959
 stack_depot_save+0x37e/0x470 lib/stackdepot.c:300
 save_stack mm/kasan/common.c:72 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x1a5/0x1e0 mm/kasan/common.c:529
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xd0/0x210 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 __alloc_skb+0x78/0x4d0 net/core/skbuff.c:198
 alloc_skb include/linux/skbuff.h:1060 [inline]
 nlmsg_new include/net/netlink.h:888 [inline]
 rtmsg_ifinfo_build_skb+0x81/0x180 net/core/rtnetlink.c:3503
 rollback_registered_many+0xd78/0x1370 net/core/dev.c:8621
 rollback_registered net/core/dev.c:8659 [inline]
 unregister_netdevice_queue+0x333/0x500 net/core/dev.c:9755
 unregister_netdevice include/linux/netdevice.h:2725 [inline]
 __tun_detach+0xfe5/0x1af0 drivers/net/tun.c:740
 tun_detach drivers/net/tun.c:757 [inline]
 tun_chr_close+0x8e/0xd0 drivers/net/tun.c:3534
 __fput+0x261/0x680 fs/file_table.c:281
 task_work_run+0x186/0x1b0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xce6/0x2d30 kernel/exit.c:812
 do_group_exit+0x136/0x300 kernel/exit.c:910
 __do_sys_exit_group kernel/exit.c:921 [inline]
 __se_sys_exit_group kernel/exit.c:919 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:919

Memory state around the buggy address:
 ffff8881c282b080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881c282b100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881c282b180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff8881c282b200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881c282b280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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