bridge0: received packet on veth0_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): P542/1:b..l P545/1:b..l rcu: (detected by 0, t=10502 jiffies, g=238265, q=428 ncpus=1) task:syz.9.5264 state:R running task stack:25000 pid:545 tgid:541 ppid:22190 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x107/0x120 kernel/softirq.c:457 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:936 [inline] __dev_queue_xmit+0x797/0x46b0 net/core/dev.c:4846 dev_queue_xmit include/linux/netdevice.h:3381 [inline] neigh_resolve_output net/core/neighbour.c:1594 [inline] neigh_resolve_output+0x53a/0x940 net/core/neighbour.c:1574 neigh_output include/net/neighbour.h:556 [inline] ip_finish_output2+0x7f8/0x21a0 net/ipv4/ip_output.c:237 __ip_finish_output.part.0+0x1b4/0x350 net/ipv4/ip_output.c:315 __ip_finish_output include/net/dst.h:464 [inline] ip_finish_output net/ipv4/ip_output.c:325 [inline] NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip_mc_output+0x4b9/0xc40 net/ipv4/ip_output.c:422 dst_output include/net/dst.h:464 [inline] dst_output include/net/dst.h:462 [inline] ip_local_out net/ipv4/ip_output.c:131 [inline] ip_send_skb net/ipv4/ip_output.c:1508 [inline] ip_push_pending_frames+0x419/0x5d0 net/ipv4/ip_output.c:1528 raw_sendmsg+0x1473/0x34f0 net/ipv4/raw.c:657 inet_sendmsg+0x11c/0x140 net/ipv4/af_inet.c:859 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] sock_write_iter+0x509/0x610 net/socket.c:1195 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7d3/0x11d0 fs/read_write.c:686 ksys_write+0x1f8/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa8b618f7c9 RSP: 002b:00007fa8b70aa038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fa8b63e6090 RCX: 00007fa8b618f7c9 RDX: 00000000000005b4 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fa8b6213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa8b63e6128 R14: 00007fa8b63e6090 R15: 00007ffe00d01b38 task:syz.9.5264 state:R running task stack:26808 pid:542 tgid:541 ppid:22190 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__sanitizer_cov_trace_pc+0x66/0x70 kernel/kcov.c:235 Code: 82 48 16 00 00 83 f8 02 75 20 48 8b 8a 50 16 00 00 8b 92 4c 16 00 00 48 8b 01 48 83 c0 01 48 39 d0 73 07 48 89 01 48 89 34 c1 45 28 ba 09 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90003ef7380 EFLAGS: 00000283 RAX: 000000000001221f RBX: ffff8880206ec618 RCX: ffffc9000cd2b000 RDX: 0000000000080000 RSI: ffffffff84def7f3 RDI: 0000000000000001 RBP: 1ffff920007dee73 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: ffff88802fd60b30 R12: ffff8880a1fd7468 R13: 0000000000000820 R14: 00000000ffffffff R15: 0000000000000000 ref_tracker_alloc+0xc3/0x5b0 lib/ref_tracker.c:265 __netdev_tracker_alloc include/linux/netdevice.h:4400 [inline] netdev_hold include/linux/netdevice.h:4429 [inline] dst_init+0xda/0x580 net/core/dst.c:52 dst_alloc+0xbb/0x1a0 net/core/dst.c:93 rt_dst_alloc+0x35/0x3a0 net/ipv4/route.c:1651 __mkroute_output net/ipv4/route.c:2655 [inline] ip_route_output_key_hash_rcu+0x87a/0x28e0 net/ipv4/route.c:2875 ip_route_output_key_hash+0x10f/0x2b0 net/ipv4/route.c:2705 __ip_route_output_key include/net/route.h:169 [inline] ip_route_output_flow+0x27/0x150 net/ipv4/route.c:2932 raw_sendmsg+0xd75/0x34f0 net/ipv4/raw.c:628 inet_sendmsg+0x11c/0x140 net/ipv4/af_inet.c:859 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0x973/0xc30 net/socket.c:2592 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2646 __sys_sendmmsg+0x200/0x420 net/socket.c:2735 __do_sys_sendmmsg net/socket.c:2762 [inline] __se_sys_sendmmsg net/socket.c:2759 [inline] __x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2759 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa8b618f7c9 RSP: 002b:00007fa8b70cb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fa8b63e5fa0 RCX: 00007fa8b618f7c9 RDX: 00000000000009a6 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fa8b6213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000e000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa8b63e6038 R14: 00007fa8b63e5fa0 R15: 00007ffe00d01b38 rcu: rcu_preempt kthread starved for 10477 jiffies! g238265 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:28248 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1139/0x6150 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6960 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 23594 Comm: kworker/u11:5 Tainted: G U W L XTNJ syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [W]=WARN, [L]=SOFTLOCKUP, [X]=AUX, [T]=RANDSTRUCT, [N]=TEST, [J]=FWCTL Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: bat_events batadv_dat_purge RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline] RIP: 0010:unwind_next_frame+0x1671/0x20b0 arch/x86/kernel/unwind_orc.c:680 Code: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 7b 05 00 00 49 8d 7d 10 49 8b 6d 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa <48> c1 ea 03 80 3c 02 00 0f 85 4e 05 00 00 49 8b 45 10 48 39 dd 0f RSP: 0018:ffffc90000006c50 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffc90000006df0 RCX: ffffffff9126361a RDX: ffffc90000006cd0 RSI: 0000000000000001 RDI: ffffc90000006cd0 RBP: ffffc90000000000 R08: ffffffff9126361e R09: 0000000039529a68 R10: 0000000000000002 R11: 000000000000a8fc R12: ffffc90000006d10 R13: ffffc90000006cc0 R14: ffffc90000006df0 R15: ffffc90000006cf4 FS: 0000000000000000(0000) GS:ffff8881248fc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd0a2d7b7c CR3: 000000000e184000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kmem_cache_free+0x2d8/0x770 mm/slub.c:6781 kfree_skbmem+0x1a4/0x1f0 net/core/skbuff.c:1130 __kfree_skb net/core/skbuff.c:1197 [inline] sk_skb_reason_drop+0x136/0x1a0 net/core/skbuff.c:1234 kfree_skb_reason include/linux/skbuff.h:1322 [inline] ip_rcv_finish_core+0x11d3/0x2290 net/ipv4/ip_input.c:430 ip_rcv_finish+0x12a/0x5b0 net/ipv4/ip_input.c:451 ip_sabotage_in+0x21e/0x290 net/bridge/br_netfilter_hooks.c:990 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623 nf_hook.constprop.0+0x424/0x750 include/linux/netfilter.h:273 NF_HOOK include/linux/netfilter.h:316 [inline] ip_rcv+0x7d/0x600 net/ipv4/ip_input.c:573 __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6139 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6252 netif_receive_skb_internal net/core/dev.c:6338 [inline] netif_receive_skb+0x137/0x760 net/core/dev.c:6397 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_pass_frame_up+0x346/0x490 net/bridge/br_input.c:70 br_handle_frame_finish+0x10e8/0x1f00 net/bridge/br_input.c:235 br_nf_hook_thresh+0x307/0x410 net/bridge/br_netfilter_hooks.c:1167 br_nf_pre_routing_finish+0xb7c/0x1830 net/bridge/br_netfilter_hooks.c:425 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_pre_routing+0xf7b/0x15b0 net/bridge/br_netfilter_hooks.c:534 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0xb28/0x14e0 net/bridge/br_input.c:442 __netif_receive_skb_core.constprop.0+0x6b3/0x35b0 net/core/dev.c:6026 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6137 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6252 process_backlog+0x4a2/0x1650 net/core/dev.c:6604 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7668 napi_poll net/core/dev.c:7731 [inline] net_rx_action+0x9f9/0xfa0 net/core/dev.c:7883 handle_softirqs+0x219/0x950 kernel/softirq.c:622 do_softirq kernel/softirq.c:523 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:510 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:396 [inline] __batadv_dat_purge.part.0+0x279/0x3a0 net/batman-adv/distributed-arp-table.c:185 __batadv_dat_purge net/batman-adv/distributed-arp-table.c:166 [inline] batadv_dat_purge+0x4b/0xa0 net/batman-adv/distributed-arp-table.c:204 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 net_ratelimit: 10926 callbacks suppressed 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 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 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 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 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) net_ratelimit: 11065 callbacks suppressed 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 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 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 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)