bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9764/1:b..l rcu: (detected by 1, t=10502 jiffies, g=330237, q=1286 ncpus=2) task:syz.3.9738 state:R running task stack:27464 pid:9764 tgid:9763 ppid:7028 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__asan_memset+0x8/0x50 mm/kasan/shadow.c:83 Code: 00 e9 bc e4 ff ff 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 <48> 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 RSP: 0018:ffffc9000eb472b8 EFLAGS: 00000246 RAX: 1ffff92001d68e7c RBX: ffffc9000eb473e0 RCX: 1ffff92001d68e01 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc9000eb473f8 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff81723db5 R10: ffffc9000eb473f8 R11: ffffffff81aad930 R12: ffffc9000eb479c0 R13: ffffc9000eb473f8 R14: ffffc9000eb473a8 R15: ffffc9000eb473f0 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 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2906 discard_slab mm/slub.c:3301 [inline] __put_partials+0x146/0x170 mm/slub.c:3848 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3923 __slab_free+0x2b9/0x390 mm/slub.c:5882 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4946 [inline] slab_alloc_node mm/slub.c:5245 [inline] __do_kmalloc_node mm/slub.c:5602 [inline] __kmalloc_noprof+0x3c3/0x7f0 mm/slub.c:5615 kmalloc_noprof include/linux/slab.h:961 [inline] sk_prot_alloc+0xe7/0x220 net/core/sock.c:2239 sk_alloc+0x3a/0x370 net/core/sock.c:2295 __netlink_create+0x65/0x260 net/netlink/af_netlink.c:628 __netlink_kernel_create+0x131/0x710 net/netlink/af_netlink.c:2020 netlink_kernel_create include/linux/netlink.h:62 [inline] audit_net_init+0xbb/0x1f0 kernel/audit.c:1694 ops_init+0x35c/0x5c0 net/core/net_namespace.c:137 setup_net+0xfe/0x320 net/core/net_namespace.c:445 copy_net_ns+0x34e/0x4e0 net/core/net_namespace.c:580 create_new_namespaces+0x3f3/0x720 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:218 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3129 __do_sys_unshare kernel/fork.c:3200 [inline] __se_sys_unshare kernel/fork.c:3198 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3198 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: 0033:0x7fcad418eec9 RSP: 002b:00007fcad23f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fcad43e5fa0 RCX: 00007fcad418eec9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007fcad4211f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcad43e6038 R14: 00007fcad43e5fa0 R15: 00007fcad450fa28 rcu: rcu_preempt kthread starved for 4541 jiffies! g330237 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:27256 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 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+0x439/0x7d0 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__lock_acquire+0x6ba/0xd20 kernel/locking/lockdep.c:5207 Code: a9 00 00 18 00 0f 84 b3 00 00 00 4c 89 f6 ba 08 00 00 00 e8 88 25 00 00 45 31 ff 85 c0 0f 84 f5 05 00 00 83 3d b6 b9 b9 17 00 <75> 13 48 63 44 24 20 48 0f a3 05 27 2a b6 11 0f 83 15 05 00 00 31 RSP: 0018:ffffc90000006ae8 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff92f338a8 RDX: 0000000000000008 RSI: ffffffff8da95d58 RDI: ffffffff8da95200 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81723db5 R10: ffffc90000006d38 R11: ffffffff81aad930 R12: 0000000000000003 R13: 0000000000000001 R14: ffffffff8da95d58 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888126378000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000099030 CR3: 000000000db36000 CR4: 00000000003526f0 DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000081 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 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:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4946 [inline] slab_alloc_node mm/slub.c:5245 [inline] kmem_cache_alloc_noprof+0x367/0x6e0 mm/slub.c:5252 skb_clone+0x212/0x3a0 net/core/skbuff.c:2050 deliver_clone net/bridge/br_forward.c:125 [inline] br_flood+0x414/0x6a0 net/bridge/br_forward.c:250 br_handle_frame_finish+0x15a3/0x1c50 net/bridge/br_input.c:229 br_nf_hook_thresh+0x3c3/0x4a0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x999/0xd60 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x37e/0x6b0 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+0x97f/0x14c0 net/bridge/br_input.c:442 __netif_receive_skb_core+0x10b9/0x4380 net/core/dev.c:5966 __netif_receive_skb_one_core net/core/dev.c:6077 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6192 process_backlog+0x60e/0x14f0 net/core/dev.c:6544 __napi_poll+0xc4/0x360 net/core/dev.c:7594 napi_poll net/core/dev.c:7657 [inline] net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784 handle_softirqs+0x283/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 93 0c 10 00 f3 0f 1e fa fb f4 88 e6 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8da07d80 EFLAGS: 000002c2 RAX: c712ef901bc60300 RBX: ffffffff81952927 RCX: c712ef901bc60300 RDX: 0000000000000001 RSI: ffffffff8d5154f6 RDI: ffffffff8b9ee960 RBP: ffffffff8da07eb8 R08: ffff8880b8832fdb R09: 1ffff110171065fb R10: dffffc0000000000 R11: ffffed10171065fc R12: ffffffff8f5c2230 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1b52a40 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e7/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 rest_init+0x2de/0x300 init/main.c:757 start_kernel+0x3ae/0x410 init/main.c:1111 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147 net_ratelimit: 14735 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 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:32:98:d1:e9:d2:09, 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 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:32:98:d1:e9:d2:09, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 19670 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:32:98:d1:e9:d2:09, 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 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:32:98:d1:e9:d2:09, 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 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:32:98:d1:e9:d2:09, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)