ip6_tunnel: ip6tnl4 xmit: Local address not yet configured! ip6_tunnel:  xmit: Local address not yet configured! rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24609/1:b..l rcu: (detected by 0, t=10503 jiffies, g=346449, q=883011 ncpus=2) task:syz.1.12756 state:R running task stack:24432 pid:24609 tgid:24606 ppid:22455 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1840/0x57a0 kernel/sched/core.c:7189 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xe1/0x130 kernel/softirq.c:457 local_bh_enable include/linux/bottom_half.h:33 [inline] ipt_do_table+0x137f/0x15d0 net/ipv4/netfilter/ip_tables.c:357 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook+0x22a/0x3a0 include/linux/netfilter.h:273 __ip_local_out+0x558/0x6a0 net/ipv4/ip_output.c:120 ip_local_out+0x2a/0x190 net/ipv4/ip_output.c:129 ip_send_skb+0x45/0xc0 net/ipv4/ip_output.c:1509 udp_send_skb+0x7f7/0xfb0 net/ipv4/udp.c:1161 udp_sendmsg+0x1971/0x2140 net/ipv4/udp.c:1443 sock_sendmsg_nosec net/socket.c:788 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x853/0xa20 net/socket.c:2699 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2753 __sys_sendmmsg+0x27c/0x4e0 net/socket.c:2842 __do_sys_sendmmsg net/socket.c:2869 [inline] __se_sys_sendmmsg net/socket.c:2866 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2866 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f31f119ce59 RSP: 002b:00007f31f212b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f31f1415fa0 RCX: 00007f31f119ce59 RDX: 000000000800001d RSI: 0000200000007fc0 RDI: 0000000000000006 RBP: 00007f31f1232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f31f1416038 R14: 00007f31f1415fa0 R15: 00007ffc33311fa8 rcu: rcu_preempt kthread starved for 1927 jiffies! g346449 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:27688 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1840/0x57a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x389/0x470 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: 0 UID: 0 PID: 17545 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:118 [inline] RIP: 0010:lock_release+0x5a/0x3c0 kernel/locking/lockdep.c:5881 Code: 11 83 f8 08 0f 83 56 02 00 00 89 c0 48 0f a3 05 8c 99 8e 0e 73 0d e8 a5 f0 08 00 84 c0 0f 84 94 02 00 00 83 3d 66 cc 8e 0e 00 <0f> 84 1c 02 00 00 65 8b 05 29 02 97 11 85 c0 0f 85 0d 02 00 00 65 RSP: 0018:ffffc90000006958 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffc90000006a78 RCX: 0000000080000102 RDX: ffffc90000006a01 RSI: ffffffff8c288600 RDI: ffffffff8c2885c0 RBP: 1ffffffff2295801 R08: ffffc90000007d30 R09: 0000000000000000 R10: ffffc90000006ab8 R11: fffff52000000d59 R12: ffffc90000000000 R13: ffffffff81769f7f R14: ffffffff8e95c780 R15: ffffc90000007d40 FS: 0000000000000000(0000) GS:ffff88812529d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005555762fb4e8 CR3: 000000002aa1e000 CR4: 00000000003526f0 Call Trace: rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:869 [inline] class_rcu_destructor include/linux/rcupdate.h:1181 [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:4570 [inline] slab_alloc_node mm/slub.c:4899 [inline] kmem_cache_alloc_noprof+0x2b8/0x650 mm/slub.c:4906 dst_alloc+0x105/0x170 net/core/dst.c:90 rt_dst_alloc net/ipv4/route.c:1649 [inline] __mkroute_output net/ipv4/route.c:2652 [inline] ip_route_output_key_hash_rcu+0x14ac/0x2720 net/ipv4/route.c:2872 ip_route_output_key_hash+0x18d/0x2a0 net/ipv4/route.c:2702 __ip_route_output_key include/net/route.h:169 [inline] ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2929 ip_route_output_key include/net/route.h:179 [inline] ip_route_me_harder+0x762/0xfe0 net/ipv4/netfilter.c:54 synproxy_send_tcp+0x347/0x670 net/netfilter/nf_synproxy_core.c:434 synproxy_send_client_synack+0x89b/0xde0 net/netfilter/nf_synproxy_core.c:487 nft_synproxy_eval_v4+0x37b/0x530 net/netfilter/nft_synproxy.c:60 nft_synproxy_do_eval+0x335/0x550 net/netfilter/nft_synproxy.c:142 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x48d/0x1ad0 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162 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+0x21f/0x3c0 include/linux/netfilter.h:316 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6204 [inline] __netif_receive_skb net/core/dev.c:6317 [inline] process_backlog+0xa34/0x1860 net/core/dev.c:6668 __napi_poll+0xaa/0x330 net/core/dev.c:7727 napi_poll net/core/dev.c:7790 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7947 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 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 e9 db ce 8a f5 cc RSP: 0018:ffffc90005f8f2b8 EFLAGS: 00000293 RAX: ffffffff8206906b RBX: ffffea0000497f00 RCX: ffff888031440000 RDX: 0000000000000000 RSI: 0000018000000000 RDI: 0000018000000000 RBP: ffffc90005f8f390 R08: ffffea0000497f07 R09: 1ffffd4000092fe0 R10: dffffc0000000000 R11: fffff94000092fe1 R12: 00fff3800000422c R13: 0000018000000000 R14: 1ffff92000bf1e5c R15: 1ffffd4000092fe0 lru_gen_inc_refs mm/swap.c:407 [inline] folio_mark_accessed+0x30b/0x8b0 mm/swap.c:466 zap_present_folio_ptes mm/memory.c:1657 [inline] zap_present_ptes mm/memory.c:1730 [inline] do_zap_pte_range mm/memory.c:1832 [inline] zap_pte_range mm/memory.c:1934 [inline] zap_pmd_range mm/memory.c:2020 [inline] zap_pud_range mm/memory.c:2048 [inline] zap_p4d_range mm/memory.c:2069 [inline] __zap_vma_range+0x1f75/0x4c70 mm/memory.c:2109 unmap_vmas+0x390/0x550 mm/memory.c:2178 exit_mmap+0x293/0x9f0 mm/mmap.c:1300 __mmput+0x118/0x420 kernel/fork.c:1178 exit_mm+0x1e4/0x2b0 kernel/exit.c:582 do_exit+0x6cd/0x2360 kernel/exit.c:964 do_group_exit+0x22d/0x2f0 kernel/exit.c:1119 get_signal+0x121b/0x12c0 kernel/signal.c:3038 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0xa9/0x6b0 kernel/entry/common.c:98 __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: 0033:0x7fedd975d68e Code: Unable to access opcode bytes at 0x7fedd975d664. RSP: 002b:00007fff3e5355a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: 0000000000000000 RBX: 0000555577219500 RCX: 00007fedd975d68e RDX: 00007fff3e535600 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fff3e53566c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000014f R13: 000000000000005e R14: 0000000000199706 R15: 00007fff3e5356c0