bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26825/1:b..l P24571/1:b..l rcu: (detected by 0, t=10503 jiffies, g=234737, q=967 ncpus=2) task:syz-executor state:R running task stack:22096 pid:24571 tgid:24571 ppid:1 task_flags:0x40054c flags:0x08080003 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __raw_read_unlock include/linux/rwlock_api_smp.h:256 [inline] _raw_read_unlock+0x3f/0x50 kernel/locking/spinlock.c:264 zap_pid_ns_processes+0x2b5/0x5f0 kernel/pid_namespace.c:233 find_child_reaper kernel/exit.c:657 [inline] forget_original_parent kernel/exit.c:741 [inline] exit_notify kernel/exit.c:778 [inline] do_exit+0x1fd8/0x2360 kernel/exit.c:1021 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152 get_signal+0x121b/0x12c0 kernel/signal.c:3046 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_int80_emulation+0x31a/0x550 arch/x86/entry/syscall_32.c:175 asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:598 RIP: 0023:0xf71b72eb RSP: 002b:00000000f759fc4c EFLAGS: 00000246 ORIG_RAX: 000000000000010b RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 00000000f759fce4 RSI: 00000000f759fcdc RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 task:syz.7.6664 state:R running task stack:25296 pid:26825 tgid:26823 ppid:24571 task_flags:0x400040 flags:0x08080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:unwind_next_frame+0x16e/0x2550 arch/x86/kernel/unwind_orc.c:510 Code: fa 19 00 00 49 8d 5e 35 48 89 d8 48 c1 e8 03 48 89 04 24 42 0f b6 04 20 84 c0 0f 85 92 1c 00 00 4c 89 7c 24 10 4c 89 6c 24 50 <0f> b6 1b 48 8b 44 24 20 42 80 3c 20 00 4d 8d 7e 48 74 08 4c 89 ff RSP: 0000:ffffc9000cce69e0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc9000cce6abd RCX: 0000000080000001 RDX: 00000000cdac3f13 RSI: ffffffff8c4bdc60 RDI: ffffffff8c4bdc20 RBP: 1ffff9200199cd58 R08: ffffffff8177827f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59c60 R12: dffffc0000000000 R13: ffffffff8177827f R14: ffffc9000cce6a88 R15: 1ffff9200199cd51 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 __set_page_owner+0x8d/0x4c0 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_pages_mpol+0x212/0x380 mm/mempolicy.c:2490 folio_alloc_mpol_noprof+0x39/0x160 mm/mempolicy.c:2509 shmem_alloc_folio mm/shmem.c:1907 [inline] shmem_alloc_and_add_folio+0x43e/0xf60 mm/shmem.c:1949 shmem_get_folio_gfp+0x5da/0x16d0 mm/shmem.c:2502 shmem_fault+0x179/0x390 mm/shmem.c:2703 __do_fault+0x138/0x2a0 mm/memory.c:5425 do_read_fault mm/memory.c:5860 [inline] do_fault mm/memory.c:5994 [inline] do_pte_missing+0x2215/0x34b0 mm/memory.c:4566 handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault mm/memory.c:6517 [inline] handle_mm_fault+0x1b36/0x3080 mm/memory.c:6686 do_user_addr_fault+0x744/0x1340 arch/x86/mm/fault.c:1394 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0010:rep_movs_alternative+0x30/0xa0 arch/x86/lib/copy_user_64.S:60 Code: 83 f9 08 73 25 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 e9 cd 61 04 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 <48> 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08 RSP: 0000:ffffc9000cce78f8 EFLAGS: 00050206 RAX: 00007ffffffff001 RBX: 000000000000001c RCX: 000000000000001c RDX: 0000000000000001 RSI: 000000008010d000 RDI: ffffc9000cce7960 RBP: ffffc9000cce79f0 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200199cf2f R12: dffffc0000000000 R13: ffffc9000cce7ca0 R14: ffffc9000cce7960 R15: 000000008010d000 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] _inline_copy_from_user include/linux/uaccess.h:185 [inline] _copy_from_user+0x7a/0xb0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:222 [inline] get_compat_msghdr+0xb3/0x4c0 net/compat.c:90 recvmsg_copy_msghdr net/socket.c:2868 [inline] ___sys_recvmsg+0x1db/0x5a0 net/socket.c:2942 do_recvmmsg+0x38b/0x7f0 net/socket.c:3033 __sys_recvmmsg+0x1a5/0x290 net/socket.c:3115 __do_compat_sys_recvmmsg_time32 net/compat.c:417 [inline] __se_compat_sys_recvmmsg_time32 net/compat.c:413 [inline] __ia32_compat_sys_recvmmsg_time32+0xbf/0xe0 net/compat.c:413 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fb30ec RSP: 002b:00000000f545550c EFLAGS: 00000206 ORIG_RAX: 0000000000000151 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800000c0 RDX: 0000000000010106 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 5246 jiffies! g234737 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:27496 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 kthread+0x388/0x470 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: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198 Code: f7 e8 ad dc cf f5 f7 c3 00 02 00 00 74 05 e8 a0 be fb f5 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 b4 f2 c0 f5 65 8b 05 ad 82 99 07 85 c0 74 18 5b 41 5e e9 91 48 RSP: 0000:ffffc90000006e58 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000292 RCX: 0000000080000102 RDX: 0000000000000000 RSI: ffffffff8e22c5c1 RDI: 0000000000000001 RBP: ffff88802b6972b0 R08: ffffffff90578d37 R09: 1ffffffff20af1a6 R10: dffffc0000000000 R11: fffffbfff20af1a7 R12: 0000000000000000 R13: ffff888168c54000 R14: ffffffff9aa822e0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124f50000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000005807f21c CR3: 00000000419c6000 CR4: 00000000003526f0 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:1180 [inline] debug_check_no_obj_freed+0x39e/0x450 lib/debugobjects.c:1201 slab_free_hook mm/slub.c:2608 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0xfd/0x650 mm/slub.c:6504 kfree_skb_reason include/linux/skbuff.h:1323 [inline] kfree_skb include/linux/skbuff.h:1332 [inline] ip6_mc_input+0x909/0xbc0 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:6212 [inline] __netif_receive_skb net/core/dev.c:6325 [inline] netif_receive_skb_internal net/core/dev.c:6411 [inline] netif_receive_skb+0x278/0xbf0 net/core/dev.c:6470 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:318 br_handle_frame_finish+0x1192/0x1990 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+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x382/0x6f0 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+0x127f/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x989/0x30b0 net/core/dev.c:6099 __netif_receive_skb_one_core net/core/dev.c:6210 [inline] __netif_receive_skb net/core/dev.c:6325 [inline] process_backlog+0x706/0x1860 net/core/dev.c:6676 __napi_poll+0xaa/0x330 net/core/dev.c:7735 napi_poll net/core/dev.c:7798 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7955 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: fc 7e 02 e9 13 05 03 00 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 53 ae 18 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0000:ffffffff8e807de0 EFLAGS: 00000246 RAX: 00000000027c5935 RBX: ffffffff819b4450 RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8e22c5c1 RDI: ffffffff8c4bdc80 RBP: ffffffff8e807eb8 R08: ffff8880b86338db R09: 1ffff110170c671b R10: dffffc0000000000 R11: ffffed10170c671c R12: 0000000000000000 R13: 1ffffffff1d11de8 R14: 1ffffffff1d00fc4 R15: dffffc0000000000 arch_safe_halt arch/x86/kernel/process.c:767 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:768 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x2e0/0x540 kernel/sched/idle.c:355 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454 rest_init+0x2de/0x300 init/main.c:717 start_kernel+0x392/0x3e0 init/main.c:1175 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x157 bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:52:ff:68:50:d6:ab, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:52:ff:68:50:d6:ab, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:52:ff:68:50:d6:ab, vlan:1) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:1)