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BUG: KASAN: use-after-free in __write_once_size include/linux/compiler.h:295 [inline]
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:789 [inline]
BUG: KASAN: use-after-free in detach_timer kernel/time/timer.c:824 [inline]
BUG: KASAN: use-after-free in detach_if_pending+0x160/0x360 kernel/time/timer.c:841
Write of size 8 at addr ffff8881d3eab1c0 by task syz-executor.3/507

CPU: 1 PID: 507 Comm: syz-executor.3 Not tainted 5.4.274-syzkaller-00002-g6f97bd951d82 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x600 mm/kasan/report.c:384
 __kasan_report+0xf3/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 __write_once_size include/linux/compiler.h:295 [inline]
 __hlist_del include/linux/list.h:789 [inline]
 detach_timer kernel/time/timer.c:824 [inline]
 detach_if_pending+0x160/0x360 kernel/time/timer.c:841
 try_to_del_timer_sync kernel/time/timer.c:1267 [inline]
 del_timer_sync+0x13c/0x230 kernel/time/timer.c:1410
 tun_flow_uninit+0x2c/0x280 drivers/net/tun.c:1452
 tun_free_netdev+0x77/0x190 drivers/net/tun.c:2402
 netdev_run_todo+0xb7f/0xdf0 net/core/dev.c:9458
 tun_detach drivers/net/tun.c:766 [inline]
 tun_chr_close+0xc1/0x130 drivers/net/tun.c:3558
 __fput+0x262/0x680 fs/file_table.c:281
 task_work_run+0x140/0x170 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x190/0x1a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode+0x199/0x200 arch/x86/entry/common.c:194
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fc880400d9a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 03 7f 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 63 7f 02 00 8b 44 24
RSP: 002b:00007fffb8efb7d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fc880400d9a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: ffffffffffffffff R08: 0000000000000001 R09: 0000001800000000
R10: 00007fc880385000 R11: 0000000000000293 R12: 00007fc880538f80
R13: 00007fc880538f8c R14: 0000000000000032 R15: 00007fc88053a980

The buggy address belongs to the page:
page:ffffea00074faac0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 0000000000000000 ffffea00076ab008 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 0x102800(GFP_NOWAIT|__GFP_NOWARN|__GFP_HARDWALL)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893
 __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+0x35a/0x480 lib/stackdepot.c:267
 save_stack mm/kasan/common.c:72 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x21c/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kfree+0x123/0x370 mm/slub.c:4071
 kobject_cleanup lib/kobject.c:722 [inline]
 kobject_release lib/kobject.c:747 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x21a/0x2f0 lib/kobject.c:764
 net_rx_queue_update_kobjects+0x3b5/0x420 net/core/net-sysfs.c:1024
 remove_queue_kobjects net/core/net-sysfs.c:1662 [inline]
 netdev_unregister_kobject+0x100/0x240 net/core/net-sysfs.c:1816
 rollback_registered_many+0xed6/0x1330 net/core/dev.c:8655
 rollback_registered net/core/dev.c:8673 [inline]
 unregister_netdevice_queue+0x333/0x500 net/core/dev.c:9767
 unregister_netdevice include/linux/netdevice.h:2726 [inline]
 __tun_detach+0x8de/0x1390 drivers/net/tun.c:747
 tun_detach drivers/net/tun.c:763 [inline]
 tun_chr_close+0x8f/0x130 drivers/net/tun.c:3558
 __fput+0x262/0x680 fs/file_table.c:281
 task_work_run+0x140/0x170 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xcaf/0x2bc0 kernel/exit.c:859
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+0x847/0x950 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4955 [inline]
 __free_pages mm/page_alloc.c:4961 [inline]
 free_pages+0xf6/0x1b0 mm/page_alloc.c:4969
 stack_depot_save+0x42b/0x480 lib/stackdepot.c:300
 save_stack mm/kasan/common.c:72 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x21c/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kfree+0x123/0x370 mm/slub.c:4071
 kobject_cleanup lib/kobject.c:722 [inline]
 kobject_release lib/kobject.c:747 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x21a/0x2f0 lib/kobject.c:764
 net_rx_queue_update_kobjects+0x3b5/0x420 net/core/net-sysfs.c:1024
 remove_queue_kobjects net/core/net-sysfs.c:1662 [inline]
 netdev_unregister_kobject+0x100/0x240 net/core/net-sysfs.c:1816
 rollback_registered_many+0xed6/0x1330 net/core/dev.c:8655
 rollback_registered net/core/dev.c:8673 [inline]
 unregister_netdevice_queue+0x333/0x500 net/core/dev.c:9767
 unregister_netdevice include/linux/netdevice.h:2726 [inline]
 __tun_detach+0x8de/0x1390 drivers/net/tun.c:747
 tun_detach drivers/net/tun.c:763 [inline]
 tun_chr_close+0x8f/0x130 drivers/net/tun.c:3558
 __fput+0x262/0x680 fs/file_table.c:281
 task_work_run+0x140/0x170 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xcaf/0x2bc0 kernel/exit.c:859
 do_group_exit+0x138/0x300 kernel/exit.c:982

Memory state around the buggy address:
 ffff8881d3eab080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881d3eab100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881d3eab180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff8881d3eab200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881d3eab280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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