================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {INITIAL USE} -> {IN-NMI} usage. syz.0.12369/13556 [HC1[1]:SC0[0]:HE0:SE1] takes: ffff88805641c238 (&trie->lock){....}-{2:2}, at: trie_delete_elem+0x8e/0x620 kernel/bpf/lpm_trie.c:466 {INITIAL USE} state was registered at: lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 trie_delete_elem+0x8e/0x620 kernel/bpf/lpm_trie.c:466 0xffffffffa000098e bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_prog_run_pin_on_cpu include/linux/filter.h:631 [inline] bpf_prog_run_clear_cb+0x95/0x1b0 include/linux/filter.h:785 run_ebpf_filter drivers/net/tun.c:1065 [inline] tun_net_xmit+0x637/0x14a0 drivers/net/tun.c:1108 __netdev_start_xmit include/linux/netdevice.h:4894 [inline] netdev_start_xmit include/linux/netdevice.h:4908 [inline] xmit_one net/core/dev.c:3695 [inline] dev_hard_start_xmit+0x292/0x8b0 net/core/dev.c:3711 sch_direct_xmit+0x24d/0x4a0 net/sched/sch_generic.c:345 __dev_xmit_skb net/core/dev.c:3932 [inline] __dev_queue_xmit+0x180d/0x3810 net/core/dev.c:4337 neigh_output include/net/neighbour.h:545 [inline] ip6_finish_output2+0xdc6/0x15c0 net/ipv6/ip6_output.c:138 dst_output include/net/dst.h:453 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] ndisc_send_skb+0xc04/0x1520 net/ipv6/ndisc.c:513 addrconf_dad_completed+0x836/0xd90 net/ipv6/addrconf.c:4303 addrconf_dad_work+0xc68/0x1500 net/ipv6/addrconf.c:-1 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 irq event stamp: 782 hardirqs last enabled at (781): [] syscall_enter_from_user_mode+0x21/0x80 kernel/entry/common.c:117 hardirqs last disabled at (782): [] exc_debug_kernel arch/x86/kernel/traps.c:1039 [inline] hardirqs last disabled at (782): [] exc_debug+0x6e/0x130 arch/x86/kernel/traps.c:1175 softirqs last enabled at (636): [] rcu_lock_acquire include/linux/rcupdate.h:350 [inline] softirqs last enabled at (636): [] rcu_read_lock include/linux/rcupdate.h:791 [inline] softirqs last enabled at (636): [] __rhashtable_remove_fast include/linux/rhashtable.h:1074 [inline] softirqs last enabled at (636): [] rhltable_remove include/linux/rhashtable.h:1134 [inline] softirqs last enabled at (636): [] toggle_bp_slot+0x1a2/0x2b30 kernel/events/hw_breakpoint.c:464 softirqs last disabled at (634): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last disabled at (634): [] rht_lock+0x1c/0x150 include/linux/rhashtable.h:329 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&trie->lock); lock(&trie->lock); *** DEADLOCK *** no locks held by syz.0.12369/13556. stack backtrace: CPU: 1 PID: 13556 Comm: syz.0.12369 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: <#DB> dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 lock_acquire+0x2df/0x4a0 kernel/locking/lockdep.c:5667 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 trie_delete_elem+0x8e/0x620 kernel/bpf/lpm_trie.c:466 bpf_prog_2c29ac5cdc6b1842+0x3a/0x3e bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x50b/0x790 kernel/events/core.c:10321 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9496 perf_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 perf_bp_event+0x311/0x3f0 kernel/events/core.c:10518 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline] hw_breakpoint_exceptions_notify+0x14d/0x470 arch/x86/kernel/hw_breakpoint.c:586 notifier_call_chain kernel/notifier.c:87 [inline] atomic_notifier_call_chain+0x17a/0x2b0 kernel/notifier.c:225 notify_die+0x141/0x1a0 kernel/notifier.c:593 notify_debug+0x20/0x30 arch/x86/kernel/traps.c:1018 exc_debug_kernel arch/x86/kernel/traps.c:1075 [inline] exc_debug+0xd9/0x130 arch/x86/kernel/traps.c:1175 asm_exc_debug+0x1a/0x40 arch/x86/include/asm/idtentry.h:648 RIP: 0010:has_zero arch/x86/include/asm/word-at-a-time.h:49 [inline] RIP: 0010:do_strncpy_from_user lib/strncpy_from_user.c:54 [inline] RIP: 0010:strncpy_from_user+0x14c/0x340 lib/strncpy_from_user.c:139 Code: 89 e6 e8 77 2d 45 fd 49 83 fc 07 0f 86 9a 00 00 00 4c 89 74 24 08 48 c7 44 24 10 f8 ff ff ff 45 31 ed 4c 89 3c 24 4f 8b 3c 2f <48> b8 ff fe fe fe fe fe fe fe 49 8d 2c 07 4d 89 fe 49 f7 d6 48 b8 RSP: 0018:ffffc9000c69fb50 EFLAGS: 00040246 RAX: ffffffff843d0489 RBX: ffffc9000c69fc70 RCX: ffff888023eada00 RDX: 0000000000000002 RSI: 000000000000007f RDI: 0000000000000007 RBP: 0000000000000000 R08: ffff888023eada00 R09: 0000000000000003 R10: 0000000000000002 R11: 0000000000000002 R12: 000000000000007f R13: 0000000000000000 R14: 000000000000007f R15: 00007465004c5047 strncpy_from_bpfptr include/linux/bpfptr.h:85 [inline] bpf_prog_load+0x200/0x1530 kernel/bpf/syscall.c:2535 __sys_bpf+0x5b8/0x780 kernel/bpf/syscall.c:5032 __do_sys_bpf kernel/bpf/syscall.c:5136 [inline] __se_sys_bpf kernel/bpf/syscall.c:5134 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5134 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f769639e019 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:00007f76972e4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f7696626090 RCX: 00007f769639e019 RDX: 0000000000000094 RSI: 0000200000000100 RDI: 0000000000000005 RBP: 00007f769643500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7696626128 R14: 00007f7696626090 R15: 00007ffca69c2da8 ---------------- Code disassembly (best guess): 0: 89 e6 mov %esp,%esi 2: e8 77 2d 45 fd call 0xfd452d7e 7: 49 83 fc 07 cmp $0x7,%r12 b: 0f 86 9a 00 00 00 jbe 0xab 11: 4c 89 74 24 08 mov %r14,0x8(%rsp) 16: 48 c7 44 24 10 f8 ff movq $0xfffffffffffffff8,0x10(%rsp) 1d: ff ff 1f: 45 31 ed xor %r13d,%r13d 22: 4c 89 3c 24 mov %r15,(%rsp) 26: 4f 8b 3c 2f mov (%r15,%r13,1),%r15 * 2a: 48 b8 ff fe fe fe fe movabs $0xfefefefefefefeff,%rax <-- trapping instruction 31: fe fe fe 34: 49 8d 2c 07 lea (%r15,%rax,1),%rbp 38: 4d 89 fe mov %r15,%r14 3b: 49 f7 d6 not %r14 3e: 48 rex.W 3f: b8 .byte 0xb8