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 veth0_vlan left promiscuous mode ================================================================== BUG: KASAN: use-after-free in vlan_dev_get_iflink+0x6d/0x70 net/8021q/vlan_dev.c:771 Read of size 4 at addr ffff8881291520d0 by task kworker/u4:4/768 CPU: 1 PID: 768 Comm: kworker/u4:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 Workqueue: netns cleanup_net Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0x10f/0x150 mm/kasan/report.c:444 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 vlan_dev_get_iflink+0x6d/0x70 net/8021q/vlan_dev.c:771 dev_get_iflink+0x70/0xc0 net/core/dev.c:724 default_operstate net/core/link_watch.c:41 [inline] rfc2863_policy+0x124/0x2b0 net/core/link_watch.c:53 linkwatch_do_dev+0x3b/0x160 net/core/link_watch.c:160 linkwatch_forget_dev+0x180/0x190 net/core/link_watch.c:238 netdev_run_todo+0x289/0x950 net/core/dev.c:10714 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:112 default_device_exit_batch+0x363/0x3c0 net/core/dev.c:11711 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x605/0xae0 net/core/net_namespace.c:599 process_one_work+0x6c8/0xbb0 kernel/workqueue.c:2328 worker_thread+0xaa0/0x1250 kernel/workqueue.c:2475 kthread+0x3f5/0x4f0 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 289: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] ____kasan_kmalloc mm/kasan/common.c:512 [inline] __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:521 kasan_kmalloc include/linux/kasan.h:227 [inline] __kmalloc+0x13d/0x2c0 mm/slub.c:4436 __kmalloc_node include/linux/slab.h:487 [inline] kmalloc_node include/linux/slab.h:642 [inline] kvmalloc_node+0x211/0x320 mm/util.c:621 kvmalloc include/linux/mm.h:865 [inline] kvzalloc include/linux/mm.h:873 [inline] alloc_netdev_mqs+0x8d/0xe20 net/core/dev.c:10927 rtnl_create_link+0x2da/0x9d0 net/core/rtnetlink.c:3244 __rtnl_newlink net/core/rtnetlink.c:3526 [inline] rtnl_newlink+0x1297/0x1900 net/core/rtnetlink.c:3584 rtnetlink_rcv_msg+0x9fd/0xcb0 net/core/rtnetlink.c:5662 netlink_rcv_skb+0x1e9/0x430 net/netlink/af_netlink.c:2520 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5680 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x86c/0xa30 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x879/0xb80 net/netlink/af_netlink.c:1923 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2071 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 768: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:193 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754 slab_free mm/slub.c:3526 [inline] kfree+0xc4/0x270 mm/slub.c:4588 kvfree+0x35/0x40 mm/util.c:661 netdev_freemem+0x3f/0x60 net/core/dev.c:10881 netdev_release+0x7f/0xb0 net/core/net-sysfs.c:1903 device_release+0x96/0x1c0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:713 [inline] kobject_release lib/kobject.c:744 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x18a/0x270 lib/kobject.c:761 netdev_run_todo+0x7dc/0x950 net/core/dev.c:10737 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:112 default_device_exit_batch+0x363/0x3c0 net/core/dev.c:11711 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x605/0xae0 net/core/net_namespace.c:599 process_one_work+0x6c8/0xbb0 kernel/workqueue.c:2328 worker_thread+0xaa0/0x1250 kernel/workqueue.c:2475 kthread+0x3f5/0x4f0 kernel/kthread.c:337 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 The buggy address belongs to the object at ffff888129152000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 208 bytes inside of 4096-byte region [ffff888129152000, ffff888129153000) The buggy address belongs to the page: page:ffffea0004a45400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888129150000 pfn:0x129150 head:ffffea0004a45400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 ffffea0004694208 ffffea0004a42008 ffff888100043380 raw: ffff888129150000 0000000000040003 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 289, ts 24048041289, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2610 prep_new_page+0x1c/0x110 mm/page_alloc.c:2616 get_page_from_freelist+0x2d42/0x2dd0 mm/page_alloc.c:4492 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5829 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1937 [inline] new_slab+0xa0/0x4d0 mm/slub.c:2000 ___slab_alloc+0x3ac/0x840 mm/slub.c:3033 __slab_alloc+0x49/0x90 mm/slub.c:3120 slab_alloc_node mm/slub.c:3211 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc_trace+0x146/0x270 mm/slub.c:3272 kmalloc include/linux/slab.h:619 [inline] kzalloc include/linux/slab.h:750 [inline] snmp6_alloc_dev net/ipv6/addrconf.c:361 [inline] ipv6_add_dev+0x5e8/0x1150 net/ipv6/addrconf.c:411 addrconf_notify+0x582/0xe00 net/ipv6/addrconf.c:3618 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2070 [inline] call_netdevice_notifiers_extack net/core/dev.c:2082 [inline] call_netdevice_notifiers+0x119/0x190 net/core/dev.c:2096 register_netdevice+0x110a/0x1490 net/core/dev.c:10463 veth_newlink+0x8ca/0xe20 drivers/net/veth.c:1718 __rtnl_newlink net/core/rtnetlink.c:3536 [inline] rtnl_newlink+0x137f/0x1900 net/core/rtnetlink.c:3584 rtnetlink_rcv_msg+0x9fd/0xcb0 net/core/rtnetlink.c:5662 page_owner free stack trace missing Memory state around the buggy address: ffff888129151f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888129152000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888129152080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888129152100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888129152180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 289, ts 24048041289, free_ts 0 page_owner free stack trace missing device bridge_slave_1 left promiscuous mode bridge0: port 2(bridge_slave_1) 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 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 device veth1_macvtap left promiscuous mode device veth0_vlan left promiscuous mode device veth1_macvtap left promiscuous mode device veth1_macvtap left promiscuous mode