veth1_macvtap: left promiscuous mode veth0_macvtap: left promiscuous mode veth1_vlan: left promiscuous mode veth0_vlan: left promiscuous mode ================================================================== BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:992 [inline] BUG: KASAN: slab-use-after-free in detach_timer+0x107/0x300 kernel/time/timer.c:891 Write of size 8 at addr ffff88805ec81f38 by task kworker/u8:6/166 CPU: 0 UID: 0 PID: 166 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: netns cleanup_net Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 __hlist_del include/linux/list.h:992 [inline] detach_timer+0x107/0x300 kernel/time/timer.c:891 detach_if_pending kernel/time/timer.c:910 [inline] __timer_delete kernel/time/timer.c:1381 [inline] timer_delete+0x2ee/0x340 kernel/time/timer.c:1406 addrconf_del_rs_timer net/ipv6/addrconf.c:318 [inline] addrconf_ifdown+0x6e4/0x1aa0 net/ipv6/addrconf.c:3916 addrconf_notify+0x1bc/0x1050 net/ipv6/addrconf.c:-1 notifier_call_chain+0x1be/0x400 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] netif_close_many+0x2ae/0x420 net/core/dev.c:1804 unregister_netdevice_many_notify+0xb47/0x2360 net/core/dev.c:12382 unregister_netdevice_many net/core/dev.c:12475 [inline] default_device_exit_batch+0x981/0xa00 net/core/dev.c:13067 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x52b/0x940 net/core/net_namespace.c:252 cleanup_net+0x56e/0x800 net/core/net_namespace.c:704 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 166: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4515 [inline] slab_alloc_node mm/slub.c:4844 [inline] kmem_cache_alloc_node_noprof+0x22a/0x6e0 mm/slub.c:4896 kmalloc_reserve net/core/skbuff.c:613 [inline] __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:289 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast+0x2fd/0x560 lib/kobject_uevent.c:410 kobject_uevent_env+0x55f/0x9e0 lib/kobject_uevent.c:608 device_del+0x754/0x900 drivers/base/core.c:3896 rfkill_unregister+0xc3/0x230 net/rfkill/core.c:1143 wiphy_unregister+0x25e/0xb30 net/wireless/core.c:1175 ieee80211_unregister_hw+0x1e2/0x2c0 net/mac80211/main.c:1713 mac80211_hwsim_del_radio+0x28a/0x490 drivers/net/wireless/virtual/mac80211_hwsim.c:5916 hwsim_exit_net+0xf02/0xfc0 drivers/net/wireless/virtual/mac80211_hwsim.c:6807 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x49f/0x940 net/core/net_namespace.c:252 cleanup_net+0x56e/0x800 net/core/net_namespace.c:704 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 5163: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2692 [inline] slab_free mm/slub.c:6143 [inline] kmem_cache_free+0x185/0x6b0 mm/slub.c:6273 skb_kfree_head net/core/skbuff.c:1087 [inline] skb_free_head net/core/skbuff.c:1101 [inline] skb_release_data+0x6c3/0x940 net/core/skbuff.c:1128 skb_release_all net/core/skbuff.c:1203 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1217 netlink_recvmsg+0x5d6/0xa50 net/netlink/af_netlink.c:1972 sock_recvmsg_nosec net/socket.c:1078 [inline] sock_recvmsg+0x22c/0x270 net/socket.c:1100 ____sys_recvmsg+0x1f2/0x4b0 net/socket.c:2812 ___sys_recvmsg+0x215/0x590 net/socket.c:2854 __sys_recvmsg net/socket.c:2887 [inline] __do_sys_recvmsg net/socket.c:2893 [inline] __se_sys_recvmsg net/socket.c:2890 [inline] __x64_sys_recvmsg+0x1c0/0x2a0 net/socket.c:2890 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805ec81d40 which belongs to the cache skbuff_small_head of size 704 The buggy address is located 504 bytes inside of freed 704-byte region [ffff88805ec81d40, ffff88805ec82000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5ec80 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff888140ab8c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000 head: 0080000000000040 ffff888140ab8c80 dead000000000100 dead000000000122 head: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000 head: 0080000000000002 ffffea00017b2001 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2000(__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 166, tgid 166 (kworker/u8:6), ts 517939587783, free_ts 517937699838 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3269 [inline] allocate_slab+0x77/0x660 mm/slub.c:3458 new_slab mm/slub.c:3516 [inline] refill_objects+0x334/0x3c0 mm/slub.c:7153 refill_sheaf mm/slub.c:2818 [inline] __pcs_replace_empty_main+0x328/0x5f0 mm/slub.c:4592 alloc_from_pcs mm/slub.c:4695 [inline] slab_alloc_node mm/slub.c:4829 [inline] kmem_cache_alloc_node_noprof+0x4f4/0x6e0 mm/slub.c:4896 kmalloc_reserve net/core/skbuff.c:613 [inline] __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:289 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast+0x2fd/0x560 lib/kobject_uevent.c:410 kobject_uevent_env+0x55f/0x9e0 lib/kobject_uevent.c:608 device_del+0x754/0x900 drivers/base/core.c:3896 rfkill_unregister+0xc3/0x230 net/rfkill/core.c:1143 wiphy_unregister+0x25e/0xb30 net/wireless/core.c:1175 ieee80211_unregister_hw+0x1e2/0x2c0 net/mac80211/main.c:1713 mac80211_hwsim_del_radio+0x28a/0x490 drivers/net/wireless/virtual/mac80211_hwsim.c:5916 page last free pid 166 tgid 166 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xfe3/0x1170 mm/page_alloc.c:2978 device_release+0x9e/0x1d0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x228/0x560 lib/kobject.c:737 netdev_run_todo+0xc75/0xde0 net/core/dev.c:11729 ieee80211_unregister_hw+0x128/0x2c0 net/mac80211/main.c:1700 mac80211_hwsim_del_radio+0x28a/0x490 drivers/net/wireless/virtual/mac80211_hwsim.c:5916 hwsim_exit_net+0xf02/0xfc0 drivers/net/wireless/virtual/mac80211_hwsim.c:6807 ops_exit_list net/core/net_namespace.c:199 [inline] ops_undo_list+0x49f/0x940 net/core/net_namespace.c:252 cleanup_net+0x56e/0x800 net/core/net_namespace.c:704 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88805ec81e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805ec81e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805ec81f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805ec81f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805ec82000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================