device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
==================================================================
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 ffff8881e895f1c0 by task kworker/u4:3/104

CPU: 1 PID: 104 Comm: kworker/u4:3 Not tainted 5.4.290-syzkaller-00017-g6b07fcd94a6a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: netns cleanup_net
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
 del_timer+0xcf/0x140 kernel/time/timer.c:1232
 addrconf_del_rs_timer net/ipv6/addrconf.c:305 [inline]
 addrconf_ifdown+0x640/0x1a90 net/ipv6/addrconf.c:3834
 addrconf_notify+0x375/0xe50 net/ipv6/addrconf.c:3698
 notifier_call_chain kernel/notifier.c:98 [inline]
 __raw_notifier_call_chain kernel/notifier.c:399 [inline]
 raw_notifier_call_chain+0x95/0x110 kernel/notifier.c:406
 call_netdevice_notifiers_info net/core/dev.c:1670 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:1682 [inline]
 call_netdevice_notifiers net/core/dev.c:1696 [inline]
 dev_close_many+0x354/0x4f0 net/core/dev.c:1439
 rollback_registered_many+0x493/0x1330 net/core/dev.c:8627
 unregister_netdevice_many net/core/dev.c:9805 [inline]
 default_device_exit_batch+0x3e0/0x680 net/core/dev.c:10276
 ops_exit_list net/core/net_namespace.c:187 [inline]
 cleanup_net+0x6e2/0xc90 net/core/net_namespace.c:612
 process_one_work+0x765/0xd20 kernel/workqueue.c:2290
 worker_thread+0xaef/0x1470 kernel/workqueue.c:2436
 kthread+0x2da/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:ffffea0007a257c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x8000000000000000()
raw: 8000000000000000 ffffea00078aa608 ffffea0007a25788 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 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO)
 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
 __vmalloc_area_node mm/vmalloc.c:2431 [inline]
 __vmalloc_node_range+0x384/0x710 mm/vmalloc.c:2499
 vmalloc_user+0x70/0x80 mm/vmalloc.c:2629
 kcov_mmap+0x28/0x120 kernel/kcov.c:450
 call_mmap include/linux/fs.h:1996 [inline]
 mmap_region+0x110d/0x16f0 mm/mmap.c:1812
 do_mmap+0x822/0xd30 mm/mmap.c:1581
 do_mmap_pgoff include/linux/mm.h:2480 [inline]
 vm_mmap_pgoff+0x1b5/0x260 mm/util.c:528
 ksys_mmap_pgoff+0x168/0x1e0 mm/mmap.c:1631
 do_syscall_64+0xca/0x1c0 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_pcp_prepare mm/page_alloc.c:1233 [inline]
 free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085
 free_unref_page mm/page_alloc.c:3134 [inline]
 free_the_page mm/page_alloc.c:4953 [inline]
 __free_pages+0xaf/0x140 mm/page_alloc.c:4961
 __vunmap+0x75b/0x890 mm/vmalloc.c:2260
 kcov_put kernel/kcov.c:396 [inline]
 kcov_close+0x27/0x50 kernel/kcov.c:495
 __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:861
 do_group_exit+0x138/0x300 kernel/exit.c:984
 __do_sys_exit_group kernel/exit.c:995 [inline]
 __se_sys_exit_group kernel/exit.c:993 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:993
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881e895f080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e895f100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881e895f180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff8881e895f200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881e895f280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================