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BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:814 [inline]
BUG: KASAN: use-after-free in enqueue_timer+0x9e/0x2c0 kernel/time/timer.c:541
Write of size 8 at addr ffff8881e48031c8 by task kworker/0:8/570

CPU: 0 PID: 570 Comm: kworker/0:8 Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
Call Trace:
 __dump_stack+0x1e/0x20 lib/dump_stack.c:77
 dump_stack+0x15b/0x1b8 lib/dump_stack.c:118
 print_address_description+0x8d/0x4c0 mm/kasan/report.c:384
 __kasan_report+0xef/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/generic_report.c:137
 hlist_add_head include/linux/list.h:814 [inline]
 enqueue_timer+0x9e/0x2c0 kernel/time/timer.c:541
 __mod_timer+0x574/0x1150 kernel/time/timer.c:1062
 mod_timer+0x1f/0x30 kernel/time/timer.c:1117
 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+0x145/0x450 drivers/net/wireguard/send.c:276
 process_one_work+0x73b/0xcc0 kernel/workqueue.c:2290
 worker_thread+0xa5c/0x13b0 kernel/workqueue.c:2436
 kthread+0x31e/0x3a0 kernel/kthread.c:288
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354

The buggy address belongs to the page:
page:ffffea00079200c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea00079200c8 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 0x152dc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_ZERO)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x35e/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x1296/0x1310 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x202/0x4b0 mm/page_alloc.c:4894
 __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]
 kmalloc_order mm/slab_common.c:1342 [inline]
 kmalloc_order_trace+0x31/0x100 mm/slab_common.c:1358
 kmalloc_large include/linux/slab.h:485 [inline]
 __kmalloc+0x162/0x2f0 mm/slub.c:3902
 __kmalloc_node include/linux/slab.h:422 [inline]
 kmalloc_node include/linux/slab.h:599 [inline]
 kvmalloc_node+0x88/0xf0 mm/util.c:596
 kvmalloc include/linux/mm.h:761 [inline]
 kvzalloc include/linux/mm.h:769 [inline]
 bpf_check+0xfb/0x9cf0 kernel/bpf/verifier.c:9561
 bpf_prog_load+0xa5f/0xe10 kernel/bpf/syscall.c:1724
 __do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
 __se_sys_bpf+0x435/0x570 kernel/bpf/syscall.c:2849
 __x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:2849
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
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+0x7e4/0x910 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4956 [inline]
 __free_pages+0x8c/0x110 mm/page_alloc.c:4962
 kfree+0x1ca/0x260 mm/slub.c:4068
 kvfree+0x4c/0x50 mm/util.c:625
 bpf_check+0x8371/0x9cf0 kernel/bpf/verifier.c:9731
 bpf_prog_load+0xa5f/0xe10 kernel/bpf/syscall.c:1724
 __do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
 __se_sys_bpf+0x435/0x570 kernel/bpf/syscall.c:2849
 __x64_sys_bpf+0x7b/0x90 kernel/bpf/syscall.c:2849
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881e4803080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e4803100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881e4803180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff8881e4803200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e4803280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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