================================================================== BUG: KASAN: slab-out-of-bounds in __write_once_size include/linux/compiler.h:295 [inline] BUG: KASAN: slab-out-of-bounds in __hlist_del include/linux/list.h:789 [inline] BUG: KASAN: slab-out-of-bounds in detach_timer kernel/time/timer.c:824 [inline] BUG: KASAN: slab-out-of-bounds in detach_if_pending+0x12d/0x330 kernel/time/timer.c:841 Write of size 8 at addr ffff8881e29371c0 by task kworker/u4:0/7 CPU: 0 PID: 7 Comm: kworker/u4:0 Tainted: G W 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 ip6_tnl_exit_batch_net+0x3cc/0x410 net/ipv6/ip6_tunnel.c:2284 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 Allocated by task 3040: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x162/0x200 mm/kasan/common.c:529 kasan_kmalloc+0xd/0x20 mm/kasan/common.c:543 __kmalloc+0x12a/0x2f0 mm/slub.c:3913 kmalloc include/linux/slab.h:561 [inline] kzalloc include/linux/slab.h:690 [inline] fib6_info_alloc+0x34/0xe0 net/ipv6/ip6_fib.c:154 ip6_route_info_create+0x4d2/0x1510 net/ipv6/route.c:3672 addrconf_f6i_alloc+0x154/0x360 net/ipv6/route.c:4461 ipv6_add_addr+0x40b/0xd40 net/ipv6/addrconf.c:1114 inet6_addr_add+0x44c/0x950 net/ipv6/addrconf.c:3007 inet6_rtm_newaddr+0x68e/0x930 net/ipv6/addrconf.c:4894 rtnetlink_rcv_msg+0xa23/0xbe0 net/core/rtnetlink.c:5290 netlink_rcv_skb+0x1e6/0x430 net/netlink/af_netlink.c:2467 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5308 netlink_unicast_kernel net/netlink/af_netlink.c:1306 [inline] netlink_unicast+0x88b/0xa40 net/netlink/af_netlink.c:1332 netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:638 [inline] __sock_sendmsg net/socket.c:650 [inline] __sys_sendto+0x414/0x570 net/socket.c:1961 __do_sys_sendto net/socket.c:1973 [inline] __se_sys_sendto net/socket.c:1969 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:1969 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8881e2937000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 448 bytes inside of 512-byte region [ffff8881e2937000, ffff8881e2937200) The buggy address belongs to the page: page:ffffea00078a4d00 refcount:1 mapcount:0 mapping:ffff8881f5c02500 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c02500 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL) 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_slab_page+0x3c/0x3b0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x93/0x420 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x29e/0x420 mm/slub.c:2667 __slab_alloc+0x63/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] __kmalloc+0x176/0x2f0 mm/slub.c:3909 __kmalloc_node include/linux/slab.h:422 [inline] kmalloc_node include/linux/slab.h:599 [inline] kzalloc_node include/linux/slab.h:701 [inline] qdisc_alloc+0x7f/0x7e0 net/sched/sch_generic.c:864 qdisc_create_dflt+0x69/0x270 net/sched/sch_generic.c:937 attach_one_default_qdisc net/sched/sch_generic.c:1089 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2194 [inline] attach_default_qdiscs net/sched/sch_generic.c:1108 [inline] dev_activate+0x2ec/0xc80 net/sched/sch_generic.c:1154 __dev_open+0x2d3/0x3f0 net/core/dev.c:1335 __dev_change_flags+0x20a/0x6a0 net/core/dev.c:7958 dev_change_flags+0x88/0x1a0 net/core/dev.c:8029 do_setlink+0xb98/0x39e0 net/core/rtnetlink.c:2542 __rtnl_newlink net/core/rtnetlink.c:3188 [inline] rtnl_newlink+0x1136/0x15f0 net/core/rtnetlink.c:3314 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: ffff8881e2937080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881e2937100: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881e2937180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8881e2937200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881e2937280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== 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