bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) ================================================================== BUG: KASAN: use-after-free in rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75 Read of size 8 at addr ffff88812833a590 by task kworker/0:5/1274 CPU: 0 PID: 1274 Comm: kworker/0:5 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: wg-crypt-wg2 wg_packet_decrypt_worker 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_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:309 rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75 rcu_do_batch+0x412/0xbf0 kernel/rcu/tree.c:2510 rcu_core+0x4a3/0xef0 kernel/rcu/tree.c:2763 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2776 handle_softirqs+0x250/0x560 kernel/softirq.c:583 __do_softirq+0xb/0xd kernel/softirq.c:621 do_softirq+0xdc/0x130 kernel/softirq.c:470 __local_bh_enable_ip+0x75/0x80 kernel/softirq.c:397 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_bh+0x51/0x60 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:409 [inline] ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline] wg_packet_decrypt_worker+0xd2c/0xda0 drivers/net/wireguard/receive.c:506 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 1519: 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 include/linux/slab.h:624 [inline] kzalloc include/linux/slab.h:750 [inline] l2tp_session_create+0x39/0xb60 net/l2tp/l2tp_core.c:1616 pppol2tp_connect+0xbf5/0x1640 net/l2tp/l2tp_ppp.c:772 __sys_connect_file net/socket.c:1923 [inline] __sys_connect+0x3cb/0x450 net/socket.c:1940 __do_sys_connect net/socket.c:1950 [inline] __se_sys_connect net/socket.c:1947 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:1947 x64_sys_call+0x7c/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:43 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 318: 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 l2tp_session_free net/l2tp/l2tp_core.c:168 [inline] l2tp_session_put+0xaf/0x1a0 net/l2tp/l2tp_core.c:193 l2tp_session_delete+0x3a9/0x4a0 net/l2tp/l2tp_core.c:1589 l2tp_tunnel_closeall net/l2tp/l2tp_core.c:1235 [inline] l2tp_tunnel_del_work+0x180/0x3d0 net/l2tp/l2tp_core.c:1273 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 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu_common kernel/rcu/tree.c:3011 [inline] call_rcu+0x10b/0xf60 kernel/rcu/tree.c:3129 pppol2tp_release+0x1e3/0x2b0 net/l2tp/l2tp_ppp.c:447 __sock_release net/socket.c:649 [inline] sock_close+0xb8/0x200 net/socket.c:1336 __fput+0x22b/0x900 fs/file_table.c:311 ____fput+0x15/0x20 fs/file_table.c:339 task_work_run+0x127/0x190 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88812833a400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 400 bytes inside of 512-byte region [ffff88812833a400, ffff88812833a600) The buggy address belongs to the page: page:ffffea0004a0ce00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x128338 head:ffffea0004a0ce00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 0000000c00000001 ffff888100042f00 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 289, ts 20173872340, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2607 prep_new_page+0x1c/0x110 mm/page_alloc.c:2613 get_page_from_freelist+0x2c3a/0x2cd0 mm/page_alloc.c:4487 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5824 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] __kmalloc+0x16a/0x2c0 mm/slub.c:4432 __kmalloc_node include/linux/slab.h:487 [inline] kmalloc_node include/linux/slab.h:642 [inline] kzalloc_node include/linux/slab.h:761 [inline] qdisc_alloc+0x79/0x7b0 net/sched/sch_generic.c:891 qdisc_create_dflt+0x6b/0x390 net/sched/sch_generic.c:953 attach_one_default_qdisc net/sched/sch_generic.c:1116 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2411 [inline] attach_default_qdiscs net/sched/sch_generic.c:1134 [inline] dev_activate+0x28e/0x1030 net/sched/sch_generic.c:1193 __dev_open+0x3e9/0x500 net/core/dev.c:1567 __dev_change_flags+0x1e4/0x6a0 net/core/dev.c:8887 dev_change_flags+0x80/0x1a0 net/core/dev.c:8958 do_setlink+0xc95/0x2970 net/core/rtnetlink.c:2783 __rtnl_newlink net/core/rtnetlink.c:3454 [inline] rtnl_newlink+0x1598/0x1900 net/core/rtnetlink.c:3576 page_owner free stack trace missing Memory state around the buggy address: ffff88812833a480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88812833a500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88812833a580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88812833a600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88812833a680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== net_ratelimit: 138132 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:5a:c6:07:30:63:38, vlan:0)