bridge0: received packet on veth1_to_bridge with own address as source address (addr:fa:2a:0f:67:ee:c4, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7407/1:b..l rcu: (detected by 1, t=10502 jiffies, g=21573, q=1617 ncpus=2) task:syz.1.457 state:R running task stack:25640 pid:7407 tgid:7407 ppid:5630 task_flags:0x400040 flags:0x00080002 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:lockdep_enabled kernel/locking/lockdep.c:121 [inline] RIP: 0010:lock_acquire+0x91/0x350 kernel/locking/lockdep.c:5844 Code: 83 3d d2 84 b5 0e 00 0f 84 d3 00 00 00 48 8b b4 24 90 00 00 00 4c 89 ef e8 3c b0 91 00 83 3d b5 84 b5 0e 00 0f 84 ce 00 00 00 <65> 8b 05 98 a0 ca 11 85 c0 0f 85 bf 00 00 00 65 48 8b 05 a0 5b ca RSP: 0018:ffffc90003a475a0 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8176f29c RDI: 1ffffffff1d6b38c RBP: ffffffff8176f27f R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90003a47738 R11: ffffffff81b16a10 R12: 0000000000000002 R13: ffffffff8eb59c60 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:840 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0xac/0x2550 arch/x86/kernel/unwind_orc.c:495 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 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2705 [inline] slab_free mm/slub.c:6405 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6532 kfree_skb_reason include/linux/skbuff.h:1323 [inline] __skb_queue_purge_reason include/linux/skbuff.h:3441 [inline] skb_queue_purge_reason+0x2e5/0x3a0 net/core/skbuff.c:4021 skb_queue_purge include/linux/skbuff.h:3454 [inline] packet_release+0xb81/0xd30 net/packet/af_packet.c:3184 __sock_release net/socket.c:710 [inline] sock_close+0xad/0x220 net/socket.c:1501 __fput+0x418/0xa50 fs/file_table.c:512 task_work_run+0x1d9/0x270 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:70 [inline] exit_to_user_mode_loop+0x1fa/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_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f122939de99 RSP: 002b:00007ffe6d071e58 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f1229627da0 RCX: 00007f122939de99 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f1229627da0 R08: 0000000000000006 R09: 0000000000000000 R10: 00007f1229627cb0 R11: 0000000000000246 R12: 000000000001d921 R13: 00007f122962609c R14: 000000000001d68f R15: 00007ffe6d071f60 rcu: rcu_preempt kthread starved for 3376 jiffies! g21573 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:27736 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: 1 UID: 0 PID: 3227 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026 Workqueue: bat_events batadv_tt_purge RIP: 0010:__preempt_count_add kernel/rcu/tree.c:748 [inline] RIP: 0010:rcu_is_watching+0x6/0xb0 kernel/rcu/tree.c:751 Code: e8 6f 8e 64 03 eb cc 66 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 41 57 <41> 56 53 65 ff 05 10 32 c1 11 e8 db e3 23 0a 89 c3 83 f8 08 73 65 RSP: 0018:ffffc90000a071e8 EFLAGS: 00000297 RAX: 0000000000000001 RBX: ffffc90000a07318 RCX: 0000000080000302 RDX: ffffc90000a07301 RSI: ffffffff8176f27f RDI: ffffffff8eb59c60 RBP: 1ffffffff21de901 R08: ffffc90000a08fe8 R09: 0000000000000000 R10: ffffc90000a07358 R11: fffff52000140e6d R12: ffffc90000a01000 R13: ffffffff8176f27f R14: ffffffff8eb59c60 R15: ffffc90000a08ff8 FS: 0000000000000000(0000) GS:ffff888125058000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9544defb78 CR3: 0000000075256000 CR4: 00000000003526f0 Call Trace: trace_lock_release include/trace/events/lock.h:68 [inline] lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5879 rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0x1baa/0x2550 arch/x86/kernel/unwind_orc.c:709 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:4612 [inline] slab_alloc_node mm/slub.c:4945 [inline] kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4959 skb_clone+0x212/0x3a0 net/core/skbuff.c:2110 dev_queue_xmit_nit+0x28d/0xac0 net/core/dev.c:2575 xmit_one net/core/dev.c:3885 [inline] dev_hard_start_xmit+0x1c1/0x830 net/core/dev.c:3905 __dev_queue_xmit+0x14c0/0x3820 net/core/dev.c:4878 dev_queue_xmit include/linux/netdevice.h:3446 [inline] br_dev_queue_push_xmit+0x370/0x4b0 net/bridge/br_forward.c:53 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:318 br_nf_post_routing+0xa53/0xee0 net/bridge/br_netfilter_hooks.c:964 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+0x23e/0x3f0 include/linux/netfilter.h:316 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh net/bridge/br_netfilter_hooks.c:1165 [inline] br_nf_forward_finish+0xa76/0xea0 net/bridge/br_netfilter_hooks.c:667 NF_HOOK+0x64e/0x6e0 include/linux/netfilter.h:318 br_nf_forward_ip+0x7eb/0xa30 net/bridge/br_netfilter_hooks.c:721 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+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+0x3e6/0x8d0 net/bridge/br_forward.c:245 br_handle_frame_finish+0x1175/0x1990 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+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+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_tt_global_purge net/batman-adv/translation-table.c:2301 [inline] batadv_tt_purge+0x4ae/0xa10 net/batman-adv/translation-table.c:3566 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 rescuer_thread+0x7b6/0x10b0 kernel/workqueue.c:3629 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 net_ratelimit: 8379 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:fa:2a:0f:67:ee:c4, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:fa:2a:0f:67:ee:c4, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:fa:2a:0f:67:ee:c4, vlan:0)