bridge0: received packet on veth0_to_bridge with own address as source address (addr:d2:57:05:88:d4:f7, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7191/1:b..l rcu: (detected by 1, t=10503 jiffies, g=16553, q=1830 ncpus=2) task:syz.3.305 state:R running task stack:25816 pid:7191 tgid:7191 ppid:5819 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 preempt_schedule_common+0x42/0xc0 kernel/sched/core.c:7051 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xff/0x120 kernel/softirq.c:457 nl80211_netlink_notify net/wireless/nl80211.c:21514 [inline] nl80211_netlink_notify+0x2fd/0x970 net/wireless/nl80211.c:21477 notifier_call_chain+0x99/0x3b0 kernel/notifier.c:85 blocking_notifier_call_chain kernel/notifier.c:380 [inline] blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368 netlink_release+0x166a/0x1ff0 net/netlink/af_netlink.c:761 __sock_release+0xb3/0x260 net/socket.c:662 sock_close+0x1c/0x30 net/socket.c:1455 __fput+0x3ff/0xb40 fs/file_table.c:468 task_work_run+0x150/0x240 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0x100/0x4b0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4fe/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5c1819acb9 RSP: 002b:00007ffc94f54208 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f5c18417da0 RCX: 00007f5c1819acb9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f5c18417da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f5c18417cb0 R11: 0000000000000246 R12: 000000000002db9f R13: 00007f5c1841627c R14: 000000000002daac R15: 00007f5c18416270 rcu: rcu_preempt kthread starved for 439 jiffies! g16553 f0x0 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:28760 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe4/0x5e10 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1a9/0xb00 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x21e/0x320 kernel/rcu/tree.c:2285 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 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: 3551 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:unwind_next_frame+0xbc5/0x1ea0 arch/x86/kernel/unwind_orc.c:656 Code: c1 ea 03 80 3c 02 00 0f 85 75 0e 00 00 4c 89 c0 49 c7 45 58 00 00 00 00 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 0f b6 34 10 <49> 8d 40 01 48 89 c7 48 c1 ef 03 0f b6 14 17 4c 89 c7 83 e7 07 40 RSP: 0018:ffffc90000006870 EFLAGS: 00000a02 RAX: 1ffffffff22c6be0 RBX: 0000000000000002 RCX: ffffffff91635efc RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffc90000006938 RBP: ffffc90000006928 R08: ffffffff91635f00 R09: 0000000000000007 R10: 0000000000000200 R11: 000000000001714d R12: ffffc90000006930 R13: ffffc900000068e0 R14: ffffc90000006c50 R15: ffffc90000006914 FS: 0000000000000000(0000) GS:ffff8881245dc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd399b8eb4c CR3: 000000000e392000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6674 [inline] kmem_cache_free+0x143/0x720 mm/slub.c:6785 __skb_ext_put+0x102/0x2d0 net/core/skbuff.c:7203 __skb_ext_del+0xf8/0x360 net/core/skbuff.c:7170 skb_ext_del include/linux/skbuff.h:5057 [inline] nf_bridge_info_free net/bridge/br_netfilter_hooks.c:156 [inline] br_nf_dev_queue_xmit+0x7ab/0x2a20 net/bridge/br_netfilter_hooks.c:919 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_post_routing+0xcbb/0x16a0 net/bridge/br_netfilter_hooks.c:966 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK include/linux/netfilter.h:316 [inline] br_forward_finish+0x261/0x4d0 net/bridge/br_forward.c:66 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167 br_nf_forward_finish+0x693/0xb30 net/bridge/br_netfilter_hooks.c:662 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_forward_ip.part.0+0x61e/0x820 net/bridge/br_netfilter_hooks.c:716 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:676 [inline] br_nf_forward+0xfe5/0x19f0 net/bridge/br_netfilter_hooks.c:773 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK include/linux/netfilter.h:316 [inline] __br_forward+0x2f6/0x970 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] br_flood+0x37f/0x650 net/bridge/br_forward.c:250 br_handle_frame_finish+0xf57/0x1f00 net/bridge/br_input.c:229 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167 br_nf_pre_routing_finish_ipv6+0x769/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x39c/0x8b0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x93b/0x1510 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0xa68/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core.constprop.0+0x6d7/0x3460 net/core/dev.c:6039 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6150 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6265 process_backlog+0x37a/0x1580 net/core/dev.c:6617 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7681 napi_poll net/core/dev.c:7744 [inline] net_rx_action+0xa40/0xf20 net/core/dev.c:7896 handle_softirqs+0x1ea/0x910 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0x576/0x14a0 kernel/smp.c:877 Code: b8 00 00 00 00 00 fc ff df 48 8b 54 24 10 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 6c 56 0c 00 f3 90 <41> 0f b6 45 00 41 38 c4 7c 08 84 c0 0f 85 3f 0d 00 00 8b 45 08 31 RSP: 0018:ffffc9000cd07808 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81faa9fa RDX: ffff888032d78000 RSI: ffffffff81faa9d4 RDI: ffff888032d78000 RBP: ffff8880b8540cc0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003 R13: ffffed10170a8199 R14: 0000000000000001 R15: ffff8880b843bf00 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2711 [inline] smp_text_poke_batch_finish+0x337/0xc60 arch/x86/kernel/alternative.c:2921 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x37a/0x550 kernel/jump_label.c:919 static_key_enable_cpuslocked+0x1bc/0x270 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate mm/kfence/core.c:879 [inline] toggle_allocation_gate+0xfe/0x2d0 mm/kfence/core.c:871 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 net_ratelimit: 20426 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, 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:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:04:09:85:29:17, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:a2:e7:cb:ff:07:65, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:d2:57:05:88:d4:f7, vlan:0) net_ratelimit: 20270 callbacks suppressed 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:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, 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:aa:aa:aa:aa:aa:0c, 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:a2:e7:cb:ff:07:65, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:86:04:09:85:29:17, 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:aa:aa:aa:aa:aa:0c, vlan:0)