syzbot

IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P14793/3:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=78689, q=457100 ncpus=2)
task:syz.5.2691      state:R  running task     stack:25192 pid:14793 tgid:14784 ppid:10989  task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline]
 __dev_queue_xmit+0x1d79/0x3b50 net/core/dev.c:4752
 dev_queue_xmit include/linux/netdevice.h:3361 [inline]
 neigh_hh_output include/net/neighbour.h:531 [inline]
 neigh_output include/net/neighbour.h:545 [inline]
 ip_finish_output2+0xd03/0x1160 net/ipv4/ip_output.c:235
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0x2a1/0x3c0 net/ipv4/ip_output.c:436
 dst_output include/net/dst.h:461 [inline]
 xfrm_output_resume+0x5f10/0x6170 net/xfrm/xfrm_output.c:598
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 xfrm4_output+0x1c6/0x4f0 net/ipv4/xfrm4_output.c:33
 ip_local_out net/ipv4/ip_output.c:129 [inline]
 __ip_queue_xmit+0x1106/0x1b00 net/ipv4/ip_output.c:532
 __tcp_transmit_skb+0x2215/0x3680 net/ipv4/tcp_output.c:1479
 tcp_transmit_skb net/ipv4/tcp_output.c:1497 [inline]
 tcp_connect+0x1f76/0x4ef0 net/ipv4/tcp_output.c:4160
 tcp_v4_connect+0x1110/0x1a00 net/ipv4/tcp_ipv4.c:345
 tcp_v6_connect+0xab1/0x1870 net/ipv6/tcp_ipv6.c:241
 __inet_stream_connect+0x2ab/0xe80 net/ipv4/af_inet.c:677
 inet_stream_connect+0x66/0xa0 net/ipv4/af_inet.c:748
 __sys_connect_file net/socket.c:2086 [inline]
 __sys_connect+0x313/0x440 net/socket.c:2105
 __do_sys_connect net/socket.c:2111 [inline]
 __se_sys_connect net/socket.c:2108 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2108
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7475d8ebe9
RSP: 002b:00007f7476bfe038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00007f7475fb6270 RCX: 00007f7475d8ebe9
RDX: 000000000000001c RSI: 0000200000000000 RDI: 0000000000000007
RBP: 00007f7475e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7475fb6308 R14: 00007f7475fb6270 R15: 00007f74760dfa28
 </TASK>
rcu: rcu_preempt kthread starved for 4461 jiffies! g78689 f0x2 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:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 3b 24 03 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900001578f8 EFLAGS: 00000206
RAX: b102a512cc508900 RBX: 0000000000000000 RCX: b102a512cc508900
RDX: 0000000000000001 RSI: ffffffff8dba7642 RDI: ffffffff8be33800
RBP: ffffffff84d03edf R08: 0000000000000000 R09: ffffffff84d03edf
R10: ffffc90000157a80 R11: fffff5200002af5a R12: 0000000000000000
R13: ffffffff8e8cce00 R14: 0000000000000001 R15: 0000000000000246
 debug_objects_fill_pool lib/debugobjects.c:724 [inline]
 __debug_object_init+0x30f/0x3c0 lib/debugobjects.c:737
 timer_init_key_on_stack+0x3c/0x110 kernel/time/timer.c:816
 schedule_timeout+0x119/0x270 kernel/time/sleep_timeout.c:96
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 14790 Comm: syz.5.2691 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319
Code: 76 7b 09 f6 90 0f 0b 90 90 90 eb c4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 31 c0 83 3d 57 c1 29 04 00 74 1e 83 3d 6a f1 29 04 00
RSP: 0018:ffffc90000006790 EFLAGS: 00000206
RAX: ffffc90000008000 RBX: ffffffff90beee01 RCX: ffffc900000077c8
RDX: ffffc90000006801 RSI: dffffc0000000000 RDI: ffffc90000006870
RBP: dffffc0000000000 R08: ffffc900000077b0 R09: 0000000000000000
R10: ffffc900000068b8 R11: fffff52000000d19 R12: ffffc900000077c0
R13: ffffc90000000000 R14: ffffc90000006868 R15: ffffffff8172c195
FS:  00007f7476c406c0(0000) GS:ffff888125c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000060030 CR3: 000000007630e000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x195c/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:330 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236
 dst_alloc+0x105/0x170 net/core/dst.c:89
 rt_dst_alloc net/ipv4/route.c:1645 [inline]
 __mkroute_output net/ipv4/route.c:2649 [inline]
 ip_route_output_key_hash_rcu+0x1560/0x23e0 net/ipv4/route.c:2870
 ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2700
 __ip_route_output_key include/net/route.h:169 [inline]
 ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2927
 ip_route_output_key include/net/route.h:179 [inline]
 ip_route_me_harder+0x6d2/0x1030 net/ipv4/netfilter.c:53
 synproxy_send_tcp+0x359/0x6c0 net/netfilter/nf_synproxy_core.c:431
 synproxy_send_client_synack+0x8bb/0xe20 net/netfilter/nf_synproxy_core.c:484
 nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
 nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x409/0x1920 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623
 nf_hook include/linux/netfilter.h:273 [inline]
 NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316
 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:318
 __netif_receive_skb_one_core net/core/dev.c:5991 [inline]
 __netif_receive_skb+0x143/0x380 net/core/dev.c:6104
 process_backlog+0x60e/0x14f0 net/core/dev.c:6456
 __napi_poll+0xc7/0x360 net/core/dev.c:7506
 napi_poll net/core/dev.c:7569 [inline]
 net_rx_action+0x707/0xe30 net/core/dev.c:7696
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 06 63 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 b1 5e 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 95 5e
RSP: 0018:ffffc9000c3d6fc0 EFLAGS: 00000246
RAX: ffffffff81b44cfb RBX: 1ffff110170e7f61 RCX: 0000000000080000
RDX: ffffc9000f7f1000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000c3d7140 R08: ffffffff8fa38f37 R09: 1ffffffff1f471e6
R10: dffffc0000000000 R11: fffffbfff1f471e7 R12: ffff8880b873fb08
R13: dffffc0000000000 R14: ffff8880b863b1c0 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451
 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
 ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
 wp_page_copy mm/memory.c:3618 [inline]
 do_wp_page+0x1bc2/0x5800 mm/memory.c:4013
 handle_pte_fault mm/memory.c:6068 [inline]
 __handle_mm_fault+0x1033/0x5440 mm/memory.c:6195
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364
 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:__put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:104
Code: d9 0f 01 cb 89 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 01 cb <89> 01 31 c9 0f 01 ca e9 01 44 03 00 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000c3d78b8 EFLAGS: 00050202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000200000060030
RDX: ffff888079d90000 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc9000c3d7a30 R08: ffffc9000c3d7667 R09: 1ffff9200187aecc
R10: dffffc0000000000 R11: fffff5200187aecd R12: 0000000000000002
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000200000060000
 ____sys_recvmsg+0x2ab/0x460 net/socket.c:2847
 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2876
 do_recvmmsg+0x307/0x770 net/socket.c:2971
 __sys_recvmmsg net/socket.c:3045 [inline]
 __do_sys_recvmmsg net/socket.c:3068 [inline]
 __se_sys_recvmmsg net/socket.c:3061 [inline]
 __x64_sys_recvmmsg+0x190/0x240 net/socket.c:3061
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7475d8ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7476c40038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f7475fb6090 RCX: 00007f7475d8ebe9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007f7475e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7475fb6128 R14: 00007f7475fb6090 R15: 00007f74760dfa28
 </TASK>
IPVS: lc: UDP 224.0.0.2:0 - no destination available
net_ratelimit: 4 callbacks suppressed
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
net_ratelimit: 5 callbacks suppressed
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available