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BUG: KASAN: invalid-access in hlist_is_singular_node include/linux/list.h:952 [inline]
BUG: KASAN: invalid-access in detach_if_pending+0x64/0xb0 kernel/time/timer.c:839
Write at addr fdff0000239a4d98 by task kworker/0:1/7
Pointer tag: [fd], memory tag: [f0]

CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.11.0-syzkaller #0
Hardware name: linux,dummy-virt (DT)
Workqueue: wg-crypt-wg1 wg_packet_decrypt_worker
Call trace:
 dump_backtrace+0x0/0x1b0 arch/arm64/kernel/stacktrace.c:117
 show_stack+0x18/0x70 arch/arm64/kernel/stacktrace.c:196
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0xd0/0x12c lib/dump_stack.c:120
 print_address_description+0x70/0x29c mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:396 [inline]
 kasan_report+0x134/0x380 mm/kasan/report.c:413
 report_tag_fault arch/arm64/mm/fault.c:311 [inline]
 do_tag_recovery arch/arm64/mm/fault.c:325 [inline]
 __do_kernel_fault+0x178/0x1bc arch/arm64/mm/fault.c:369
 do_bad_area arch/arm64/mm/fault.c:462 [inline]
 do_tag_check_fault+0x74/0x90 arch/arm64/mm/fault.c:717
 do_mem_abort+0x44/0xbc arch/arm64/mm/fault.c:793
 el1_abort+0x40/0x6c arch/arm64/kernel/entry-common.c:118
 el1_sync_handler+0xac/0xd0 arch/arm64/kernel/entry-common.c:209
 el1_sync+0x70/0x100 arch/arm64/kernel/entry.S:656
 hlist_is_singular_node include/linux/list.h:952 [inline]
 detach_if_pending+0x64/0xb0 kernel/time/timer.c:839
 wg_timers_any_authenticated_packet_received+0x14/0x20 drivers/net/wireguard/timers.c:178
 wg_packet_consume_data_done drivers/net/wireguard/receive.c:359 [inline]
 wg_packet_rx_poll+0x32c/0x6a0 drivers/net/wireguard/receive.c:482
 napi_poll net/core/dev.c:6806 [inline]
 net_rx_action+0x178/0x484 net/core/dev.c:6889
 _stext+0x124/0x2ac
 do_softirq_own_stack include/linux/interrupt.h:577 [inline]
 do_softirq kernel/softirq.c:246 [inline]
 do_softirq+0x98/0xa4 kernel/softirq.c:233
 __local_bh_enable_ip+0xa4/0xb0 kernel/softirq.c:196
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_bh+0x38/0x60 kernel/locking/spinlock.c:207
 spin_unlock_bh include/linux/spinlock.h:399 [inline]
 ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
 wg_packet_decrypt_worker+0xf8/0x1c0 drivers/net/wireguard/receive.c:507
 process_one_work+0x1d8/0x360 kernel/workqueue.c:2275
 worker_thread+0x70/0x434 kernel/workqueue.c:2421
 kthread+0x174/0x180 kernel/kthread.c:292
 ret_from_fork+0x10/0x34 arch/arm64/kernel/entry.S:958

Allocated by task 5931:
 stack_trace_save+0x50/0x80 kernel/stacktrace.c:121
 kasan_save_stack+0x28/0x60 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:401 [inline]
 ____kasan_kmalloc+0xe8/0x160 mm/kasan/common.c:429
 __kasan_slab_alloc+0x1c/0x30 mm/kasan/common.c:437
 kasan_slab_alloc include/linux/kasan.h:209 [inline]
 slab_post_alloc_hook mm/slab.h:512 [inline]
 slab_alloc_node mm/slub.c:2892 [inline]
 slab_alloc mm/slub.c:2900 [inline]
 __kmalloc_track_caller+0x1a8/0x324 mm/slub.c:4479
 kmemdup+0x44/0x80 mm/util.c:128
 kmemdup include/linux/string.h:520 [inline]
 __addrconf_sysctl_register+0x4c/0x1a0 net/ipv6/addrconf.c:6913
 addrconf_sysctl_register net/ipv6/addrconf.c:6978 [inline]
 addrconf_sysctl_register+0x9c/0xc0 net/ipv6/addrconf.c:6967
 ipv6_add_dev+0x28c/0x4e0 net/ipv6/addrconf.c:443
 addrconf_notify+0x250/0x94c net/ipv6/addrconf.c:3489
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x54/0x74 kernel/notifier.c:410
 call_netdevice_notifiers_info+0x58/0xa4 net/core/dev.c:2040
 call_netdevice_notifiers_extack net/core/dev.c:2052 [inline]
 call_netdevice_notifiers net/core/dev.c:2066 [inline]
 register_netdevice+0x450/0x59c net/core/dev.c:10089
 veth_newlink+0x1c0/0x38c drivers/net/veth.c:1390
 __rtnl_newlink+0x604/0x800 net/core/rtnetlink.c:3443
 rtnl_newlink+0x70/0xa0 net/core/rtnetlink.c:3491
 rtnetlink_rcv_msg+0x118/0x334 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x5c/0x130 net/netlink/af_netlink.c:2494
 rtnetlink_rcv+0x18/0x2c net/core/rtnetlink.c:5571
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x25c/0x320 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x1d4/0x3e4 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0x54/0x60 net/socket.c:672
 __sys_sendto+0x118/0x14c net/socket.c:1975
 __do_sys_sendto net/socket.c:1987 [inline]
 __se_sys_sendto net/socket.c:1983 [inline]
 __arm64_sys_sendto+0x2c/0x40 net/socket.c:1983
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:49 [inline]
 el0_svc_common.constprop.0+0x74/0x190 arch/arm64/kernel/syscall.c:159
 do_el0_svc+0x74/0x90 arch/arm64/kernel/syscall.c:198
 el0_svc+0x14/0x20 arch/arm64/kernel/entry-common.c:365
 el0_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:381
 el0_sync+0x190/0x1c0 arch/arm64/kernel/entry.S:699

Freed by task 6071:
 stack_trace_save+0x50/0x80 kernel/stacktrace.c:121
 kasan_save_stack+0x28/0x60 mm/kasan/common.c:38
 kasan_set_track+0x28/0x40 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/hw_tags.c:174
 ____kasan_slab_free.constprop.0+0x184/0x1c0 mm/kasan/common.c:362
 __kasan_slab_free+0x10/0x20 mm/kasan/common.c:369
 kasan_slab_free include/linux/kasan.h:192 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x98/0x18c mm/slub.c:1580
 slab_free mm/slub.c:3143 [inline]
 kfree+0x324/0x4a0 mm/slub.c:4139
 cleanup_uevent_env+0x14/0x20 lib/kobject_uevent.c:273
 call_usermodehelper_freeinfo kernel/umh.c:44 [inline]
 umh_complete+0x54/0x70 kernel/umh.c:59
 call_usermodehelper_exec_async+0x134/0x140 kernel/umh.c:120
 ret_from_fork+0x10/0x34 arch/arm64/kernel/entry.S:958

The buggy address belongs to the object at ffff0000239a4000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 3480 bytes inside of
 4096-byte region [ffff0000239a4000, ffff0000239a5000)
The buggy address belongs to the page:
page:0000000033af0dda refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x639a0
head:0000000033af0dda order:3 compound_mapcount:0 compound_pincount:0
flags: 0x1ffffc000010200(slab|head)
raw: 01ffffc000010200 dead000000000100 dead000000000122 f1ff000004801900
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000239a4b00: f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0
 ffff0000239a4c00: f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0
>ffff0000239a4d00: f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0
                                              ^
 ffff0000239a4e00: f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0
 ffff0000239a4f00: f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0 f0
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