================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {INITIAL USE} -> {IN-NMI} usage. syz.2.434/7676 [HC1[1]:SC0[0]:HE0:SE1] takes: ffff88802fd18da0 (&htab->lockdep_key){....}-{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_lru_map_delete_elem+0x19f/0x640 kernel/bpf/hashtab.c:1485 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:10576 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9712 perf_swevent_overflow kernel/events/core.c:9795 [inline] perf_swevent_event+0x319/0x570 kernel/events/core.c:9846 perf_bp_event+0x319/0x430 kernel/events/core.c:10773 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+0x18f/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_user arch/x86/kernel/traps.c:1168 [inline] noist_exc_debug+0x77/0x120 arch/x86/kernel/traps.c:1205 asm_exc_debug+0x33/0x40 arch/x86/include/asm/idtentry.h:644 irq event stamp: 1518 hardirqs last enabled at (1517): [] syscall_enter_from_user_mode+0x25/0x80 kernel/entry/common.c:117 hardirqs last disabled at (1518): [] exc_debug_kernel arch/x86/kernel/traps.c:1063 [inline] hardirqs last disabled at (1518): [] exc_debug+0x73/0x140 arch/x86/kernel/traps.c:1199 softirqs last enabled at (1488): [] l2tp_ip_hash net/l2tp/l2tp_ip.c:204 [inline] softirqs last enabled at (1488): [] l2tp_ip_open+0x140/0x190 net/l2tp/l2tp_ip.c:223 softirqs last disabled at (1486): [] l2tp_ip_hash net/l2tp/l2tp_ip.c:202 [inline] softirqs last disabled at (1486): [] l2tp_ip_open+0x75/0x190 net/l2tp/l2tp_ip.c:223 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&htab->lockdep_key); lock(&htab->lockdep_key); *** DEADLOCK *** no locks held by syz.2.434/7676. stack backtrace: CPU: 1 PID: 7676 Comm: syz.2.434 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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_lru_map_delete_elem+0x19f/0x640 kernel/bpf/hashtab.c:1485 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:10576 __perf_event_overflow+0x461/0x660 kernel/events/core.c:9712 perf_swevent_overflow kernel/events/core.c:9795 [inline] perf_swevent_event+0x319/0x570 kernel/events/core.c:9846 perf_bp_event+0x319/0x430 kernel/events/core.c:10773 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+0x18f/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+0x33/0x90 arch/x86/lib/copy_user_64.S:58 Code: 40 83 f9 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 RSP: 0018:ffffc900055dfae0 EFLAGS: 00040212 RAX: aa1414ac00000002 RBX: 0000000000000010 RCX: 0000000000000010 RDX: 0000000000000001 RSI: 0000200000000300 RDI: ffffc900055dfc20 RBP: 0000200000000300 R08: ffffc900055dfc2f R09: 1ffff92000abbf85 R10: dffffc0000000000 R11: fffff52000abbf86 R12: 0000200000000310 R13: ffffc900055dfbc0 R14: ffffc900055dfc20 R15: 0000200000000300 copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:127 [inline] _copy_from_user+0x8b/0xe0 lib/usercopy.c:23 copy_from_user include/linux/uaccess.h:183 [inline] move_addr_to_kernel net/socket.c:253 [inline] __copy_msghdr+0x388/0x560 net/socket.c:2498 copy_msghdr_from_user net/socket.c:2528 [inline] sendmsg_copy_msghdr net/socket.c:2626 [inline] ___sys_sendmsg+0x214/0x360 net/socket.c:2645 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2687 [inline] __se_sys_sendmsg+0x1d0/0x2c0 net/socket.c:2685 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f67ae39ce59 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:00007f67af20a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f67ae615fa0 RCX: 00007f67ae39ce59 RDX: 0900000000000000 RSI: 0000200000000500 RDI: 0000000000000009 RBP: 00007f67ae432e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f67ae616038 R14: 00007f67ae615fa0 R15: 00007ffd3b09f768 ---------------- Code disassembly (best guess): 0: 40 83 f9 08 rex cmp $0x8,%ecx 4: 73 21 jae 0x27 6: 85 c9 test %ecx,%ecx 8: 74 0f je 0x19 a: 8a 06 mov (%rsi),%al c: 88 07 mov %al,(%rdi) e: 48 ff c7 inc %rdi 11: 48 ff c6 inc %rsi 14: 48 ff c9 dec %rcx 17: 75 f1 jne 0xa 19: c3 ret 1a: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 21: 00 00 00 24: 0f 1f 00 nopl (%rax) 27: 48 8b 06 mov (%rsi),%rax * 2a: 48 89 07 mov %rax,(%rdi) <-- trapping instruction 2d: 48 83 c6 08 add $0x8,%rsi 31: 48 83 c7 08 add $0x8,%rdi 35: 83 e9 08 sub $0x8,%ecx 38: 74 df je 0x19 3a: 83 f9 08 cmp $0x8,%ecx 3d: 73 e8 jae 0x27 3f: eb .byte 0xeb