syzbot

==================================================================
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:884 [inline]
BUG: KASAN: use-after-free in detach_timer kernel/time/timer.c:886 [inline]
BUG: KASAN: use-after-free in detach_if_pending+0x156/0x300 kernel/time/timer.c:905
Write of size 8 at addr ffff88811a6949f8 by task kworker/u4:5/426

CPU: 1 PID: 426 Comm: kworker/u4:5 Not tainted 6.1.141-syzkaller-00039-g145c7fad733f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: wg-kex-wg0 wg_packet_handshake_send_worker
Call Trace:
 <TASK>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
 print_address_description+0x71/0x210 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:427
 kasan_report+0x122/0x150 mm/kasan/report.c:531
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report_generic.c:356
 __hlist_del include/linux/list.h:884 [inline]
 detach_timer kernel/time/timer.c:886 [inline]
 detach_if_pending+0x156/0x300 kernel/time/timer.c:905
 __mod_timer+0x231/0xb30 kernel/time/timer.c:1082
 mod_timer+0x1f/0x30 kernel/time/timer.c:1172
 mod_peer_timer drivers/net/wireguard/timers.c:37 [inline]
 wg_timers_any_authenticated_packet_traversal+0x133/0x1a0 drivers/net/wireguard/timers.c:215
 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:36 [inline]
 wg_packet_handshake_send_worker+0x182/0x240 drivers/net/wireguard/send.c:51
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2299
 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2446
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 6063:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:379 [inline]
 __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:388
 kasan_kmalloc include/linux/kasan.h:212 [inline]
 __do_kmalloc_node mm/slab_common.c:938 [inline]
 __kmalloc+0xb1/0x1e0 mm/slab_common.c:951
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 hci_alloc_dev_priv+0x27/0x1bd0 net/bluetooth/hci_core.c:2435
 hci_alloc_dev include/net/bluetooth/hci_core.h:1484 [inline]
 hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:641 [inline]
 hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:719 [inline]
 hci_uart_tty_ioctl+0x3d6/0xa20 drivers/bluetooth/hci_ldisc.c:774
 tty_ioctl+0x8ef/0xc60 drivers/tty/tty_io.c:2785
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856
 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 6063:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:241
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1745 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1771
 slab_free mm/slub.c:3686 [inline]
 __kmem_cache_free+0xb7/0x1b0 mm/slub.c:3702
 kfree+0x6f/0xf0 mm/slab_common.c:990
 hci_release_dev+0x13ad/0x1500 net/bluetooth/hci_core.c:2763
 bt_host_release+0x82/0x90 net/bluetooth/hci_sysfs.c:85
 device_release+0xa4/0x1d0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:681 [inline]
 kobject_release lib/kobject.c:712 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x19d/0x280 lib/kobject.c:729
 put_device+0x1f/0x30 drivers/base/core.c:3806
 hci_dev_put include/net/bluetooth/hci_core.h:1444 [inline]
 hci_dev_cmd+0x265/0x720 net/bluetooth/hci_core.c:795
 hci_sock_ioctl+0x41e/0x7f0 net/bluetooth/hci_sock.c:1096
 sock_do_ioctl+0x101/0x310 net/socket.c:1194
 sock_ioctl+0x4d8/0x6e0 net/socket.c:1311
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856
 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 insert_work+0x51/0x300 kernel/workqueue.c:1368
 __queue_work+0x9b1/0xd30 kernel/workqueue.c:1527
 queue_work_on+0xd2/0x140 kernel/workqueue.c:1555
 queue_work include/linux/workqueue.h:510 [inline]
 hci_cmd_sync_run net/bluetooth/hci_sync.c:140 [inline]
 __hci_cmd_sync_sk+0xa3e/0xcf0 net/bluetooth/hci_sync.c:162
 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:253 [inline]
 __hci_cmd_sync_status net/bluetooth/hci_sync.c:277 [inline]
 hci_cmd_sync_status+0x53/0x120 net/bluetooth/hci_sync.c:288
 hci_dev_cmd+0x628/0x720 net/bluetooth/hci_core.c:-1
 hci_sock_ioctl+0x41e/0x7f0 net/bluetooth/hci_sock.c:1096
 sock_do_ioctl+0x101/0x310 net/socket.c:1194
 sock_ioctl+0x4d8/0x6e0 net/socket.c:1311
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856
 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856
 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Second to last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 insert_work+0x51/0x300 kernel/workqueue.c:1368
 __queue_work+0x9b1/0xd30 kernel/workqueue.c:1527
 queue_work_on+0xd2/0x140 kernel/workqueue.c:1555
 queue_work include/linux/workqueue.h:510 [inline]
 hci_cmd_timeout+0x191/0x200 net/bluetooth/hci_core.c:1468
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2299
 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2446
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff88811a694000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 2552 bytes inside of
 8192-byte region [ffff88811a694000, ffff88811a696000)

The buggy address belongs to the physical page:
page:ffffea000469a400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11a690
head:ffffea000469a400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100043500
raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6061, tgid 6059 (syz.4.1527), ts 404304656510, free_ts 404222861572
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2637
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2644
 get_page_from_freelist+0x2c7b/0x2cf0 mm/page_alloc.c:4539
 __alloc_pages+0x19e/0x3a0 mm/page_alloc.c:5850
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1962 [inline]
 new_slab+0x98/0x3d0 mm/slub.c:2015
 ___slab_alloc+0x6f6/0xb50 mm/slub.c:3203
 __slab_alloc+0x5e/0xa0 mm/slub.c:3302
 slab_alloc_node mm/slub.c:3387 [inline]
 __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3462
 __do_kmalloc_node mm/slab_common.c:937 [inline]
 __kmalloc+0xa1/0x1e0 mm/slab_common.c:951
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 ops_init+0x89/0x4a0 net/core/net_namespace.c:128
 setup_net+0x4ab/0xcb0 net/core/net_namespace.c:335
 copy_net_ns+0x355/0x5c0 net/core/net_namespace.c:481
 create_new_namespaces+0x3a2/0x660 kernel/nsproxy.c:110
 copy_namespaces+0x1d1/0x220 kernel/nsproxy.c:178
 copy_process+0x12e0/0x3420 kernel/fork.c:2459
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1545 [inline]
 free_pcp_prepare mm/page_alloc.c:1619 [inline]
 free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3581
 free_unref_page+0x8f/0x530 mm/page_alloc.c:3677
 free_the_page mm/page_alloc.c:830 [inline]
 __free_pages+0x67/0x100 mm/page_alloc.c:5939
 __free_slab+0xca/0x1a0 mm/slub.c:2039
 free_slab mm/slub.c:2054 [inline]
 discard_slab mm/slub.c:2060 [inline]
 __unfreeze_partials+0x160/0x190 mm/slub.c:2609
 put_cpu_partial+0xa9/0x100 mm/slub.c:2685
 __slab_free+0x1c4/0x280 mm/slub.c:3563
 do_slab_free mm/slub.c:3640 [inline]
 ___cache_free+0xbf/0xd0 mm/slub.c:3696
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:310
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3421 [inline]
 __kmem_cache_alloc_node+0x192/0x2c0 mm/slub.c:3462
 __do_kmalloc_node mm/slab_common.c:937 [inline]
 __kmalloc_node+0xa1/0x1e0 mm/slab_common.c:945
 kmalloc_node include/linux/slab.h:589 [inline]
 __bpf_map_area_alloc kernel/bpf/syscall.c:328 [inline]
 bpf_map_area_alloc+0x4b/0xe0 kernel/bpf/syscall.c:341
 ringbuf_map_alloc+0x17c/0x2f0 kernel/bpf/ringbuf.c:204

Memory state around the buggy address:
 ffff88811a694880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811a694900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811a694980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                                ^
 ffff88811a694a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811a694a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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