bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P20743/2:b..l rcu: (detected by 1, t=10502 jiffies, g=101605, q=2003 ncpus=2) task:syz.0.3885 state:R running task stack:25800 pid:20743 tgid:20740 ppid:17800 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8b0 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_is_held_type+0x106/0x150 kernel/locking/lockdep.c:5945 Code: 1a 00 00 b8 ff ff ff ff 65 0f c1 05 64 cd 90 07 83 f8 01 75 25 9c 58 a9 00 02 00 00 75 39 41 f7 c4 00 02 00 00 74 01 fb 89 d8 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 90 0f 0b 90 48 c7 RSP: 0018:ffffc9001019f4e0 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000046 RDX: ffff888035dfdd00 RSI: ffffffff8e2172cb RDI: ffffffff8c28b8e0 RBP: 00000000ffffffff R08: ffffea0001aad2c7 R09: 1ffffd4000355a58 R10: dffffc0000000000 R11: fffff94000355a59 R12: 0000000000000246 R13: ffff888035dfdd00 R14: ffff888035972178 R15: 0000000000000003 lock_is_held include/linux/lockdep.h:249 [inline] xa_entry include/linux/xarray.h:1226 [inline] xas_reload+0xfc/0x470 include/linux/xarray.h:1624 next_uptodate_folio+0x1ea/0x6b0 mm/filemap.c:3720 filemap_map_pages+0x2a5/0x2100 mm/filemap.c:3896 do_fault_around mm/memory.c:5867 [inline] do_read_fault mm/memory.c:5900 [inline] do_fault mm/memory.c:6043 [inline] do_pte_missing+0x1f38/0x33f0 mm/memory.c:4566 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault mm/memory.c:6565 [inline] handle_mm_fault+0x1bf2/0x3170 mm/memory.c:6734 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x167f/0x2730 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:4137 [inline] vm_mmap_pgoff+0x3aa/0x4f0 mm/util.c:586 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdef339ce59 RSP: 002b:00007fdef41f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fdef3615fa0 RCX: 00007fdef339ce59 RDX: 0000000003000001 RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007fdef3432d6f R08: ffffffffffffffff R09: 00000000fffff000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdef3616038 R14: 00007fdef3615fa0 R15: 00007fffe255afe8 rcu: rcu_preempt kthread starved for 1726 jiffies! g101605 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:27640 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 11348 Comm: kworker/u8:20 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker RIP: 0010:check_preemption_disabled+0x14/0xe0 lib/smp_processor_id.c:16 Code: 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 65 8b 05 27 6e 90 07 65 8b 0d 1c 6e 90 07 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d c3 cc cc cc cc cc 9c 59 RSP: 0018:ffffc90000a07990 EFLAGS: 00000282 RAX: 0000000000000001 RBX: ffffffff90c5c301 RCX: 0000000080000102 RDX: ffffc90000a07a01 RSI: ffffffff8c28b8c0 RDI: ffffffff8c28b880 RBP: dffffc0000000000 R08: ffffc90004fbfce8 R09: 0000000000000000 R10: ffffc90000a07af8 R11: fffff52000140f61 R12: ffffc90004fbfcf8 R13: ffffc90004fb8000 R14: ffffc90000a07aa8 R15: ffffffff8176e256 FS: 0000000000000000(0000) GS:ffff8881253a0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc3cbf6b84 CR3: 0000000035628000 CR4: 00000000003526f0 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:752 rcu_read_unlock include/linux/rcupdate.h:867 [inline] class_rcu_destructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0x1b76/0x2550 arch/x86/kernel/unwind_orc.c:709 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 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:2689 [inline] slab_free mm/slub.c:6251 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6378 skb_ext_reset include/linux/skbuff.h:5118 [inline] skb_release_head_state+0x270/0x360 net/core/skbuff.c:1181 skb_release_all net/core/skbuff.c:1187 [inline] __kfree_skb+0x24/0x210 net/core/skbuff.c:1203 kfree_skb_reason include/linux/skbuff.h:1324 [inline] kfree_skb include/linux/skbuff.h:1333 [inline] ip6_mc_input+0x8de/0xbd0 net/ipv6/ip6_input.c:638 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:988 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:6202 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] netif_receive_skb_internal net/core/dev.c:6401 [inline] netif_receive_skb+0x278/0xbf0 net/core/dev.c:6460 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:318 br_handle_frame_finish+0x1541/0x1c80 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x91f/0xc30 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x374/0x6f0 net/bridge/br_netfilter_ipv6.c:183 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x1277/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x98f/0x3170 net/core/dev.c:6089 __netif_receive_skb_one_core net/core/dev.c:6200 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6666 __napi_poll+0xae/0x340 net/core/dev.c:7733 napi_poll net/core/dev.c:7796 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7953 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 wg_socket_send_skb_to_peer+0x16b/0x1d0 drivers/net/wireguard/socket.c:183 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x203/0x350 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:86:bc:ca:e3:8f:c9, vlan:0)