bridge0: received packet on veth0_to_bridge with own address as source address (addr:fa:aa:37:9b:9e:3f, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P26685/1:b..l rcu: (detected by 0, t=10502 jiffies, g=154557, q=1233 ncpus=2) task:syz.2.7399 state:R running task stack:25832 pid:26685 ppid:26226 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __local_bh_enable_ip+0x14b/0x1c0 kernel/softirq.c:413 local_bh_enable include/linux/bottom_half.h:33 [inline] xdp_test_run_batch net/bpf/test_run.c:361 [inline] bpf_test_run_xdp_live+0x18ce/0x1b30 net/bpf/test_run.c:383 bpf_prog_test_run_xdp+0x7d8/0x1140 net/bpf/test_run.c:1326 bpf_prog_test_run+0x31f/0x390 kernel/bpf/syscall.c:4132 __sys_bpf+0x49d/0x890 kernel/bpf/syscall.c:5495 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline] __se_sys_bpf kernel/bpf/syscall.c:5579 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff414b9de59 RSP: 002b:00007ff415a95028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007ff414e26180 RCX: 00007ff414b9de59 RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a RBP: 00007ff414c33e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff414e26218 R14: 00007ff414e26180 R15: 00007ffd1da2a468 rcu: rcu_preempt kthread starved for 215 jiffies! g154557 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:26824 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 26689 Comm: syz.3.7401 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_switch+0x65/0xe0 kernel/kcov.c:350 Code: 57 41 56 41 54 53 48 8d 4c 09 01 48 8b 54 24 20 65 4c 8b 05 bd cd 7c 7e 45 31 c9 eb 08 49 ff c1 4c 39 c8 74 77 4e 8b 54 ce 10 <65> 44 8b 1d ab cd 7c 7e 41 81 e3 00 01 ff 00 74 13 41 81 fb 00 01 RSP: 0018:ffffc90000006950 EFLAGS: 00000202 RAX: 0000000000000008 RBX: 0000000000000000 RCX: 0000000000000003 RDX: ffffffff813b2b18 RSI: ffffffff8cfa05c0 RDI: 0000000000000005 RBP: ffffc90000006a98 R08: ffff88805025bc00 R09: 0000000000000007 R10: 0000000000000009 R11: 0000000000000100 R12: ffffffff8f90b136 R13: ffffc90000006a48 R14: 0000000000000005 R15: dffffc0000000000 FS: 00007f22d09bd6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b33315ff8 CR3: 000000004e896000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_next_frame+0x748/0x2990 arch/x86/kernel/unwind_orc.c:515 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x290 mm/slub.c:3852 kfree_skb include/linux/skbuff.h:1264 [inline] ip6_mc_input+0xa17/0xc10 net/ipv6/ip6_input.c:589 ip_sabotage_in+0x1e2/0x270 net/bridge/br_netfilter_hooks.c:1001 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:259 [inline] NF_HOOK+0x21d/0x3b0 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5646 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5760 netif_receive_skb_internal net/core/dev.c:5846 [inline] netif_receive_skb+0x1bc/0x720 net/core/dev.c:5905 NF_HOOK+0x9e/0x3a0 include/linux/netfilter.h:304 br_handle_frame_finish+0xf51/0x15c0 net/bridge/br_input.c:221 br_nf_hook_thresh+0x3cd/0x4a0 net/bridge/br_netfilter_hooks.c:1184 br_nf_pre_routing_finish_ipv6+0x9e5/0xd20 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:304 [inline] br_nf_pre_routing_ipv6+0x34d/0x6a0 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x1240/0x14d0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xf94/0x3ab0 net/core/dev.c:5540 __netif_receive_skb_one_core net/core/dev.c:5644 [inline] __netif_receive_skb+0x74/0x290 net/core/dev.c:5760 process_backlog+0x380/0x710 net/core/dev.c:6088 __napi_poll+0xbb/0x460 net/core/dev.c:6650 napi_poll net/core/dev.c:6717 [inline] net_rx_action+0x65f/0xcc0 net/core/dev.c:6853 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__sanitizer_cov_trace_pc+0x45/0x60 kernel/kcov.c:221 Code: ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 <48> 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 RSP: 0018:ffffc9000450f370 EFLAGS: 00000246 RAX: ffffffff813b3eb0 RBX: ffffffff8f1b573e RCX: ffff88805025bc00 RDX: ffffc90013774000 RSI: 000000000000f4cf RDI: 0000000000000000 RBP: ffffc9000450f498 R08: ffff88805025bc00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000002 R12: ffffc9000450f858 R13: ffffc9000450f448 R14: 0000000000000000 R15: dffffc0000000000 get_reg arch/x86/kernel/unwind_orc.c:452 [inline] unwind_next_frame+0x1ae0/0x2990 arch/x86/kernel/unwind_orc.c:643 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 memcg_free_slab_cgroups mm/slab.h:463 [inline] unaccount_slab mm/slab.h:651 [inline] __free_slab+0xbe/0x2a0 mm/slub.c:2097 __slab_free+0x35a/0x400 mm/slub.c:3736 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] __kmem_cache_alloc_node+0x194/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] kset_create lib/kobject.c:965 [inline] kset_create_and_add+0x5a/0x160 lib/kobject.c:1008 register_queue_kobjects net/core/net-sysfs.c:1793 [inline] netdev_register_kobject+0x1b2/0x320 net/core/net-sysfs.c:2046 register_netdevice+0x12aa/0x1ba0 net/core/dev.c:10318 tun_set_iff+0x82b/0xea0 drivers/net/tun.c:2865 __tun_chr_ioctl+0x7e0/0x2070 drivers/net/tun.c:3134 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f22cfb9de59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f22d09bd028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f22cfe26090 RCX: 00007f22cfb9de59 RDX: 00002000000000c0 RSI: 00000000400454ca RDI: 0000000000000009 RBP: 00007f22cfc33e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f22cfe26128 R14: 00007f22cfe26090 R15: 00007fff3b68fb58 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 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:fa:aa:37:9b:9e:3f, 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:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:fa:aa:37:9b:9e:3f, 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)