bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8365/1:b..l rcu: (detected by 0, t=10503 jiffies, g=185049, q=2238 ncpus=2) task:syz.4.9404 state:R running task stack:24960 pid:8365 tgid:8363 ppid:7734 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7091 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457 nl80211_netlink_notify+0x46b/0x840 net/wireless/nl80211.c:21652 notifier_call_chain+0x1be/0x400 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 netlink_release+0x123b/0x1ad0 net/netlink/af_netlink.c:761 __sock_release net/socket.c:662 [inline] sock_close+0xc3/0x240 net/socket.c:1455 __fput+0x44f/0xa70 fs/file_table.c:469 task_work_run+0x1d9/0x270 kernel/task_work.c:233 get_signal+0x11eb/0x1330 kernel/signal.c:2807 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __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 include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb40b19c629 RSP: 002b:00007fb40c07f028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: 000000000000001c RBX: 00007fb40b415fa0 RCX: 00007fb40b19c629 RDX: 0000000004008054 RSI: 0000200000000200 RDI: 0000000000000005 RBP: 00007fb40b232b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb40b416038 R14: 00007fb40b415fa0 R15: 00007ffcfbfe9338 rcu: rcu_preempt kthread starved for 3123 jiffies! g185049 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:27664 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 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+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 101 PID: 5484 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:312 [inline] RIP: 0010:rcu_read_lock include/linux/rcupdate.h:850 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1193 [inline] RIP: 0010:unwind_next_frame+0xb0/0x23c0 arch/x86/kernel/unwind_orc.c:495 Code: 4f 02 00 00 89 84 24 8c 00 00 00 4c 89 bc 24 90 00 00 00 e8 92 dd 34 00 4c 8d 3d 00 00 00 00 48 c7 c7 e0 02 76 8e 31 f6 31 d2 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 de 00 2b 00 48 83 c4 08 RSP: 0018:ffffc90000a07b38 EFLAGS: 00000246 RAX: 0000000000000004 RBX: ffffffff823a05a2 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e7602e0 RBP: dffffc0000000000 R08: ffffc90000a07cd0 R09: 000000000000001a R10: ffffc90000a07c58 R11: ffffffff81b0b130 R12: 1ffff92000140f81 R13: ffffc90000a07c40 R14: ffffc90000a07c08 R15: ffffffff81767a45 FS: 00007fb30f7f5740(0000) GS:ffff888125566000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcbbea3ff58 CR3: 000000007eac6000 CR4: 00000000003526f0 Call Trace: 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 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4501 [inline] slab_alloc_node mm/slub.c:4830 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4837 skb_ext_maybe_cow net/core/skbuff.c:7092 [inline] skb_ext_add+0x1b6/0x8f0 net/core/skbuff.c:7167 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:169 [inline] br_nf_forward_ip+0xc3/0xa30 net/bridge/br_netfilter_hooks.c:681 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:316 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver net/bridge/br_forward.c:191 [inline] br_flood+0x6ee/0xb80 net/bridge/br_forward.c:238 br_handle_frame_finish+0x1492/0x1b40 net/bridge/br_input.c:229 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0xa3a/0xd70 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:184 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/0x31a0 net/core/dev.c:6041 __netif_receive_skb_one_core net/core/dev.c:6152 [inline] __netif_receive_skb net/core/dev.c:6267 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6619 __napi_poll+0xae/0x340 net/core/dev.c:7683 napi_poll net/core/dev.c:7746 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7898 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/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+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_next_frame+0x4a5/0x23c0 arch/x86/kernel/unwind_orc.c:520 Code: e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 66 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 79 18 00 00 41 0f b6 44 24 01 <83> e0 07 0f 84 66 15 00 00 83 f8 01 4c 8b 7c 24 50 48 bd 00 00 00 RSP: 0018:ffffc900033675b8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffffff9099a374 RCX: ffffffff9099a378 RDX: ffffffff914da144 RSI: ffffffff914da144 RDI: ffffffff8c27a420 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8e7602e0 R10: ffffc900033676d8 R11: ffffffff81b0b130 R12: ffffffff914da148 R13: ffffffff914da149 R14: ffffc90003367688 R15: ffffffff9099a374 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978 __slab_free+0x263/0x2b0 mm/slub.c:5532 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5219 [inline] __kmalloc_noprof+0x35c/0x760 mm/slub.c:5231 kmalloc_noprof include/linux/slab.h:966 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x246/0x630 security/tomoyo/file.c:728 security_file_ioctl+0xc3/0x2a0 security/security.c:2435 __do_sys_ioctl fs/ioctl.c:591 [inline] __se_sys_ioctl+0x47/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb30f8f5378 Code: 00 00 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 07 89 d0 c3 0f 1f 40 00 48 8b 15 49 3a 0d RSP: 002b:00007ffd6c6be278 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000055f74d9555a0 RCX: 00007fb30f8f5378 RDX: 00007ffd6c6be280 RSI: 0000000000008921 RDI: 000000000000000f RBP: 00007ffd6c6be280 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000055f74d885120 R13: 000055f74d9555a0 R14: 000055f74d885120 R15: 00007ffd6c6be4d0 net_ratelimit: 15069 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:0c, 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 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:a4:ef:d7:b0:e8, 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) net_ratelimit: 15322 callbacks suppressed 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 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: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:0c, 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: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)