bridge0: received packet on veth1_to_bridge with own address as source address (addr:3e:6e:c0:ff:b7:36, 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) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2827/1:b..l rcu: (detected by 0, t=10526 jiffies, g=191789, q=3392 ncpus=2) task:syz.3.6698 state:R running task stack:23688 pid:2827 tgid:2818 ppid:656 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7276 preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7598 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x910 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:debug_lockdep_rcu_enabled+0x29/0x40 kernel/rcu/update.c:321 Code: 90 f3 0f 1e fa 31 c0 83 3d fb f7 94 04 00 74 1d 83 3d ca 27 95 04 00 74 14 65 48 8b 0d 48 b5 af 07 31 c0 83 b9 a4 0b 00 00 00 <0f> 94 c0 e9 8f fe 02 00 cc cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 0018:ffffc900045364d8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc90004536598 RCX: ffff8880216a0000 RDX: ffffc90004536501 RSI: dffffc0000000000 RDI: ffffc90004536590 RBP: 1ffffffff233a001 R08: ffffc90004537090 R09: 0000000000000000 R10: ffffc900045365d8 R11: fffff520008a6cbd R12: ffffc90004530000 R13: ffffffff8177f1df R14: ffffc90004536588 R15: ffffc900045370a0 rcu_read_unlock include/linux/rcupdate.h:878 [inline] class_rcu_destructor include/linux/rcupdate.h:1216 [inline] unwind_next_frame+0x1b5d/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:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] kmem_cache_alloc_node_noprof+0x354/0x610 mm/slub.c:5068 __alloc_skb+0x1db/0x7a0 net/core/skbuff.c:704 alloc_skb include/linux/skbuff.h:1384 [inline] nlmsg_new include/net/netlink.h:1055 [inline] rtmsg_ifinfo_build_skb+0x7f/0x260 net/core/rtnetlink.c:4585 rtmsg_ifinfo_event net/core/rtnetlink.c:4627 [inline] rtmsg_ifinfo+0x8c/0x1a0 net/core/rtnetlink.c:4636 __dev_notify_flags+0x257/0x510 net/core/dev.c:9849 netif_change_flags+0xde/0x1b0 net/core/dev.c:9882 do_setlink+0xdd6/0x4670 net/core/rtnetlink.c:3271 rtnl_group_changelink net/core/rtnetlink.c:3924 [inline] __rtnl_newlink net/core/rtnetlink.c:4090 [inline] rtnl_newlink+0x146f/0x1c30 net/core/rtnetlink.c:4220 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7137 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] ____sys_sendmsg+0x54e/0x850 net/socket.c:2713 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767 __sys_sendmsg net/socket.c:2799 [inline] __do_sys_sendmsg net/socket.c:2804 [inline] __se_sys_sendmsg net/socket.c:2802 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2802 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7ce379e159 RSP: 002b:00007f7ce1993028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f7ce3a26270 RCX: 00007f7ce379e159 RDX: 0000000000000000 RSI: 0000200000000140 RDI: 0000000000000007 RBP: 00007f7ce383503b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7ce3a26308 R14: 00007f7ce3a26270 R15: 00007fffe79706a8 rcu: rcu_preempt kthread starved for 1023 jiffies! g191789 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7276 __schedule_loop kernel/sched/core.c:7353 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7368 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330 kthread+0x38b/0x480 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5281 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:ebt_do_table+0x25d8/0x27c0 net/bridge/netfilter/ebtables.c:312 Code: 77 f7 e9 f1 fe ff ff 4c 89 e3 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 22 ff ff ff 4c 89 e7 e8 a0 e3 77 f7 49 89 dc e9 12 ff ff ff <83> fb ff 75 0c e8 ae e3 07 f7 bb 01 00 00 00 eb 07 e8 a2 e3 07 f7 RSP: 0018:ffffc90000a180a0 EFLAGS: 00000206 RAX: 00000000fffffffc RBX: 00000000ffffffff RCX: 0000000000000005 RDX: ffffffff8abfc620 RSI: ffffffff903b6f50 RDI: 00000000ffffffff RBP: ffffc90000a18280 R08: ffff888027ab1f40 R09: 0000000000000002 R10: 00000000ffffffff R11: 8000000000000300 R12: ffffc900042b5060 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fa3f758d780(0000) GS:ffff888124dd1000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdd6c228d58 CR3: 0000000078042000 CR4: 00000000003526f0 Call Trace: nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:280 [inline] NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:323 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 br_handle_frame_finish+0x1119/0x1950 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:325 [inline] br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x1329/0x1600 net/bridge/br_input.c:451 __netif_receive_skb_core+0x989/0x30c0 net/core/dev.c:6151 __netif_receive_skb_one_core net/core/dev.c:6262 [inline] __netif_receive_skb net/core/dev.c:6377 [inline] process_backlog+0x727/0x18b0 net/core/dev.c:6728 __napi_poll+0xaa/0x330 net/core/dev.c:7787 napi_poll net/core/dev.c:7850 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8007 handle_softirqs+0x226/0x860 kernel/softirq.c:645 do_softirq+0x77/0xd0 kernel/softirq.c:546 __local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473 sockopt_release_sock net/core/sock.c:1162 [inline] sk_setsockopt+0x287d/0x2f10 net/core/sock.c:1680 unix_setsockopt+0x15f/0x340 net/unix/af_unix.c:943 do_sock_setsockopt+0x17c/0x1b0 net/socket.c:2397 __sys_setsockopt net/socket.c:2422 [inline] __do_sys_setsockopt net/socket.c:2428 [inline] __se_sys_setsockopt net/socket.c:2425 [inline] __x64_sys_setsockopt+0x13d/0x1b0 net/socket.c:2425 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa3f76925aa Code: 48 83 ec 10 48 63 c9 48 63 ff 45 89 c9 6a 2c e8 8c 4e f8 ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 8b 15 19 e8 0c 00 f7 RSP: 002b:00007ffd029d22b8 EFLAGS: 00000283 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007fa3f76925aa RDX: 0000000000000007 RSI: 0000000000000001 RDI: 0000000000000021 RBP: 0000000000000021 R08: 0000000000000004 R09: 0000000000000001 R10: 00007ffd029d22cc R11: 0000000000000283 R12: 00007ffd029d2330 R13: 0000000000000001 R14: 0000000000000000 R15: 000055ffb7f14ac0