================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {INITIAL USE} -> {IN-NMI} usage. syz.1.2648/14962 [HC1[1]:SC0[0]:HE0:SE1] takes: ffff88802fe030f8 (&htab->lockdep_key#2){....}-{2:2}, at: htab_lock_bucket+0x17d/0x300 kernel/bpf/hashtab.c:166 {INITIAL USE} state was registered at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 htab_lock_bucket+0x17d/0x300 kernel/bpf/hashtab.c:166 htab_map_update_elem+0x229/0x1040 kernel/bpf/hashtab.c:1152 bpf_map_update_value+0x660/0x720 kernel/bpf/syscall.c:203 map_update_elem+0x57b/0x700 kernel/bpf/syscall.c:1567 __sys_bpf+0x6b5/0x890 kernel/bpf/syscall.c:5465 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline] __se_sys_bpf kernel/bpf/syscall.c:5579 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 irq event stamp: 1404 hardirqs last enabled at (1403): [] seqcount_lockdep_reader_access+0x12b/0x1d0 include/linux/seqlock.h:-1 hardirqs last disabled at (1404): [] exc_debug_kernel arch/x86/kernel/traps.c:1063 [inline] hardirqs last disabled at (1404): [] exc_debug+0x73/0x140 arch/x86/kernel/traps.c:1199 softirqs last enabled at (1266): [] l2tp_ip6_hash net/l2tp/l2tp_ip6.c:214 [inline] softirqs last enabled at (1266): [] l2tp_ip6_open+0x140/0x190 net/l2tp/l2tp_ip6.c:233 softirqs last disabled at (1264): [] l2tp_ip6_hash net/l2tp/l2tp_ip6.c:212 [inline] softirqs last disabled at (1264): [] l2tp_ip6_open+0x75/0x190 net/l2tp/l2tp_ip6.c:233 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&htab->lockdep_key#2); lock(&htab->lockdep_key#2); *** DEADLOCK *** no locks held by syz.1.2648/14962. stack backtrace: CPU: 0 PID: 14962 Comm: syz.1.2648 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: <#DB> dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 lock_acquire+0x2c2/0x420 kernel/locking/lockdep.c:5745 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 htab_lock_bucket+0x17d/0x300 kernel/bpf/hashtab.c:166 htab_map_delete_elem+0x1a4/0x650 kernel/bpf/hashtab.c:1449 bpf_prog_2c29ac5cdc6b1842+0x42/0x46 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline] __bpf_prog_run include/linux/filter.h:616 [inline] bpf_prog_run include/linux/filter.h:623 [inline] bpf_overflow_handler+0x1fc/0x510 kernel/events/core.c:10584 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9720 perf_swevent_overflow+0x268/0x340 kernel/events/core.c:9803 perf_swevent_event+0x45c/0x570 kernel/events/core.c:-1 perf_bp_event+0x319/0x430 kernel/events/core.c:10781 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline] hw_breakpoint_exceptions_notify+0x23e/0x670 arch/x86/kernel/hw_breakpoint.c:586 notifier_call_chain+0x197/0x380 kernel/notifier.c:93 atomic_notifier_call_chain+0xda/0x180 kernel/notifier.c:231 notify_die+0x145/0x1a0 kernel/notifier.c:596 notify_debug+0x2e/0x50 arch/x86/kernel/traps.c:1042 exc_debug_kernel arch/x86/kernel/traps.c:1099 [inline] exc_debug+0xde/0x140 arch/x86/kernel/traps.c:1199 asm_exc_debug+0x1e/0x40 arch/x86/include/asm/idtentry.h:644 RIP: 0010:rep_movs_alternative+0x36/0x90 arch/x86/lib/copy_user_64.S:59 Code: 08 73 21 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 06 48 89 07 <48> 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 f3 a4 RSP: 0018:ffffc9000e5bf310 EFLAGS: 00040206 RAX: 6163696669726576 RBX: 000000000000001c RCX: 000000000000001c RDX: 0000000000000000 RSI: ffff88807acc068c RDI: 0000200000000300 RBP: 000000000000001c R08: ffff88807acc06a7 R09: 1ffff1100f5980d4 R10: dffffc0000000000 R11: ffffed100f5980d5 R12: 000020000000031c R13: 0000000000000000 R14: 0000200000000300 R15: ffff88807acc068c copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:133 [inline] _copy_to_user+0x85/0xa0 lib/usercopy.c:41 copy_to_user include/linux/uaccess.h:191 [inline] bpf_verifier_vlog+0x2fa/0x870 kernel/bpf/log.c:124 verbose+0x11e/0x1a0 kernel/bpf/verifier.c:370 print_verification_stats kernel/bpf/verifier.c:19787 [inline] bpf_check+0x5708/0xeba0 kernel/bpf/verifier.c:20490 bpf_prog_load+0x1163/0x1670 kernel/bpf/syscall.c:2753 __sys_bpf+0x5ba/0x890 kernel/bpf/syscall.c:5477 __do_sys_bpf kernel/bpf/syscall.c:5581 [inline] __se_sys_bpf kernel/bpf/syscall.c:5579 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f820619c819 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:00007f820703f028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f8206415fa0 RCX: 00007f820619c819 RDX: 0000000000000070 RSI: 0000200000000280 RDI: 0000000000000005 RBP: 00007f8206232c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8206416038 R14: 00007f8206415fa0 R15: 00007fff9bd877c8 ---------------- Code disassembly (best guess): 0: 08 73 21 or %dh,0x21(%rbx) 3: 85 c9 test %ecx,%ecx 5: 74 0f je 0x16 7: 8a 06 mov (%rsi),%al 9: 88 07 mov %al,(%rdi) b: 48 ff c7 inc %rdi e: 48 ff c6 inc %rsi 11: 48 ff c9 dec %rcx 14: 75 f1 jne 0x7 16: c3 ret 17: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 1e: 00 00 00 21: 0f 1f 00 nopl (%rax) 24: 48 8b 06 mov (%rsi),%rax 27: 48 89 07 mov %rax,(%rdi) * 2a: 48 83 c6 08 add $0x8,%rsi <-- trapping instruction 2e: 48 83 c7 08 add $0x8,%rdi 32: 83 e9 08 sub $0x8,%ecx 35: 74 df je 0x16 37: 83 f9 08 cmp $0x8,%ecx 3a: 73 e8 jae 0x24 3c: eb c9 jmp 0x7 3e: f3 a4 rep movsb %ds:(%rsi),%es:(%rdi)