bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29820/2:b..l rcu: (detected by 1, t=10503 jiffies, g=89973, q=489491 ncpus=2) task:syz.0.7104 state:R running task stack:22760 pid:29820 tgid:29818 ppid:26689 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline] __dev_queue_xmit+0x1d79/0x3b50 net/core/dev.c:4752 neigh_output include/net/neighbour.h:547 [inline] ip_finish_output2+0xd40/0x1160 net/ipv4/ip_output.c:235 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip_output+0x2a1/0x3c0 net/ipv4/ip_output.c:436 igmp_send_report+0x89e/0xdb0 net/ipv4/igmp.c:799 __igmp_group_dropped+0x63c/0x8f0 net/ipv4/igmp.c:1322 __ip_mc_dec_group+0x3e5/0x690 net/ipv4/igmp.c:1777 br_ip4_multicast_leave_snoopers net/bridge/br_multicast.c:4204 [inline] br_multicast_leave_snoopers+0xb6/0x1c0 net/bridge/br_multicast.c:4224 br_dev_stop+0x8a/0x180 net/bridge/br_device.c:197 __dev_close_many+0x361/0x6f0 net/core/dev.c:1755 __dev_close net/core/dev.c:1767 [inline] __dev_change_flags+0x2c7/0x6d0 net/core/dev.c:9547 netif_change_flags+0x88/0x1a0 net/core/dev.c:9612 do_setlink+0xc55/0x41c0 net/core/rtnetlink.c:3143 rtnl_changelink net/core/rtnetlink.c:3761 [inline] __rtnl_newlink net/core/rtnetlink.c:3920 [inline] rtnl_newlink+0x160b/0x1c70 net/core/rtnetlink.c:4057 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6946 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2614 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668 __sys_sendmsg net/socket.c:2700 [inline] __do_sys_sendmsg net/socket.c:2705 [inline] __se_sys_sendmsg net/socket.c:2703 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0cc338ebe9 RSP: 002b:00007f0cc41a5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f0cc35b5fa0 RCX: 00007f0cc338ebe9 RDX: 0000000000000000 RSI: 0000200000000280 RDI: 000000000000000a RBP: 00007f0cc3411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0cc35b6038 R14: 00007f0cc35b5fa0 R15: 00007ffc12984988 rcu: rcu_preempt kthread starved for 1658 jiffies! g89973 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:27496 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10354 Comm: kworker/u8:26 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:memset_orig+0x75/0xb0 arch/x86/lib/memset_64.S:92 Code: 89 47 30 48 89 47 38 48 8d 7f 40 75 d8 0f 1f 84 00 00 00 00 00 89 d1 83 e1 38 74 14 c1 e9 03 66 0f 1f 44 00 00 ff c9 48 89 07 <48> 8d 7f 08 75 f5 83 e2 07 74 0a ff ca 88 07 48 8d 7f 01 75 f6 4c RSP: 0018:ffffc900000062d0 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffffc900000063e0 RCX: 0000000000000001 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc900000063f8 RBP: dffffc0000000000 R08: ffffc90000006407 R09: 0000000000000000 R10: ffffc900000063f8 R11: fffff52000000c81 R12: ffffc90000007a60 R13: ffffc900000063f8 R14: ffffc900000063a8 R15: ffffc900000063f0 FS: 0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcbf5400218 CR3: 000000000df36000 CR4: 00000000003526f0 Call Trace: unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271 __netdev_tracker_alloc include/linux/netdevice.h:4349 [inline] netdev_hold include/linux/netdevice.h:4378 [inline] dst_init+0xd9/0x450 net/core/dst.c:52 dst_alloc+0x12a/0x170 net/core/dst.c:93 rt_dst_alloc net/ipv4/route.c:1645 [inline] ip_route_input_slow net/ipv4/route.c:2423 [inline] ip_route_input_rcu+0x1ed5/0x2ff0 net/ipv4/route.c:2537 ip_route_input_noref+0x167/0x250 net/ipv4/route.c:2548 ip_rcv_finish_core+0x5af/0x1c00 net/ipv4/ip_input.c:371 ip_rcv_finish+0x14c/0x2f0 net/ipv4/ip_input.c:452 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:993 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:5991 [inline] __netif_receive_skb+0x143/0x380 net/core/dev.c:6104 netif_receive_skb_internal net/core/dev.c:6190 [inline] netif_receive_skb+0x1cb/0x790 net/core/dev.c:6249 NF_HOOK+0xa0/0x390 include/linux/netfilter.h:319 br_handle_frame_finish+0x14d1/0x19b0 net/bridge/br_input.c:-1 br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:-1 [inline] br_nf_pre_routing_finish+0x1312/0x1a90 net/bridge/br_netfilter_hooks.c:425 NF_HOOK+0x618/0x6b0 include/linux/netfilter.h:318 br_nf_pre_routing+0xeb7/0x1470 net/bridge/br_netfilter_hooks.c:534 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0x982/0x14c0 net/bridge/br_input.c:434 __netif_receive_skb_core+0x10b9/0x4020 net/core/dev.c:5878 __netif_receive_skb_one_core net/core/dev.c:5989 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6104 process_backlog+0x60e/0x14f0 net/core/dev.c:6456 __napi_poll+0xc4/0x360 net/core/dev.c:7506 napi_poll net/core/dev.c:7569 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7696 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xd3c/0x12d0 kernel/smp.c:877 Code: 01 31 ff e8 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 0b 00 eb 38 f3 90 42 0f b6 04 2b 84 c0 75 11 <41> f7 04 24 01 00 00 00 74 1e e8 45 5e 0b 00 eb e4 44 89 e1 80 e1 RSP: 0018:ffffc9000b737660 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff110170e7f61 RCX: ffff88804ce35a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000b7377e0 R08: ffffffff8fa38537 R09: 1ffffffff1f470a6 R10: dffffc0000000000 R11: fffffbfff1f470a7 R12: ffff8880b873fb08 R13: dffffc0000000000 R14: ffff8880b863b1c0 R15: 0000000000000001 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2653 [inline] smp_text_poke_batch_finish+0x5f9/0x1130 arch/x86/kernel/alternative.c:2863 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 3463 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) net_ratelimit: 7014 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:72:7a:87:9b:cb, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)