================================================================== 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+0x12d/0x330 kernel/time/timer.c:841 Write of size 8 at addr ffff8881ea3fb1c0 by task kworker/u4:1/9 CPU: 1 PID: 9 Comm: kworker/u4:1 Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: netns cleanup_net 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 __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+0x12d/0x330 kernel/time/timer.c:841 del_timer+0x75/0xb0 kernel/time/timer.c:1232 addrconf_del_rs_timer net/ipv6/addrconf.c:305 [inline] addrconf_ifdown+0x601/0x17e0 net/ipv6/addrconf.c:3834 addrconf_notify+0x399/0xeb0 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+0xa0/0x120 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+0x2c4/0x440 net/core/dev.c:1439 rollback_registered_many+0x451/0xf40 net/core/dev.c:8627 unregister_netdevice_many+0x4b/0x290 net/core/dev.c:9805 ip_tunnel_delete_nets+0x343/0x390 net/ipv4/ip_tunnel.c:1129 ipgre_tap_exit_batch_net+0x22/0x30 net/ipv4/ip_gre.c:1709 ops_exit_list net/core/net_namespace.c:187 [inline] cleanup_net+0x5fd/0xb40 net/core/net_namespace.c:612 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:ffffea0007a8fec0 refcount:2 mapcount:1 mapping:0000000000000000 index:0x0 flags: 0x8000000000000000() raw: 8000000000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 0000000200000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated 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+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] __vmalloc_area_node mm/vmalloc.c:-1 [inline] __vmalloc_node_range+0x36a/0x6e0 mm/vmalloc.c:2499 vmalloc_user+0x73/0x80 mm/vmalloc.c:2629 kcov_mmap+0x2b/0x120 kernel/kcov.c:450 call_mmap include/linux/fs.h:1996 [inline] mmap_region+0x101b/0x15a0 mm/mmap.c:1812 do_mmap+0x826/0xd90 mm/mmap.c:1581 do_mmap_pgoff include/linux/mm.h:2480 [inline] vm_mmap_pgoff+0x195/0x230 mm/util.c:528 ksys_mmap_pgoff+0x16f/0x1e0 mm/mmap.c:1631 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:97 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:88 [inline] __x64_sys_mmap+0xfa/0x110 arch/x86/kernel/sys_x86_64.c:88 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_pcp_prepare mm/page_alloc.c:1233 [inline] free_unref_page_prepare+0x2a9/0x3a0 mm/page_alloc.c:3085 free_unref_page mm/page_alloc.c:3134 [inline] free_the_page mm/page_alloc.c:4954 [inline] __free_pages+0xaa/0x110 mm/page_alloc.c:4962 pcpu_free_pages mm/percpu-vm.c:64 [inline] pcpu_depopulate_chunk mm/percpu-vm.c:328 [inline] pcpu_balance_workfn+0x8c7/0x14b0 mm/percpu.c:1865 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 Memory state around the buggy address: ffff8881ea3fb080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881ea3fb100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881ea3fb180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff8881ea3fb200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881ea3fb280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== 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 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