================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {INITIAL USE} -> {IN-NMI} usage. syz.4.7618/29931 [HC1[1]:SC0[0]:HE0:SE1] takes: ffff8880184389a0 (&htab->lockdep_key#2){....}-{2:2}, at: htab_lock_bucket+0x179/0x2f0 kernel/bpf/hashtab.c:166 {INITIAL USE} state was registered at: lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 htab_lock_bucket+0x179/0x2f0 kernel/bpf/hashtab.c:166 htab_lru_map_update_elem+0x31e/0xe80 kernel/bpf/hashtab.c:1214 bpf_map_update_value+0x59e/0x670 kernel/bpf/syscall.c:228 map_update_elem+0x4d7/0x680 kernel/bpf/syscall.c:1473 __sys_bpf+0x4ec/0x780 kernel/bpf/syscall.c:5019 __do_sys_bpf kernel/bpf/syscall.c:5135 [inline] __se_sys_bpf kernel/bpf/syscall.c:5133 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5133 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 irq event stamp: 3274 hardirqs last enabled at (3273): [] kasan_quarantine_put+0xd4/0x220 mm/kasan/quarantine.c:242 hardirqs last disabled at (3274): [] exc_debug_kernel arch/x86/kernel/traps.c:1039 [inline] hardirqs last disabled at (3274): [] exc_debug+0x6e/0x130 arch/x86/kernel/traps.c:1175 softirqs last enabled at (3180): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last enabled at (3180): [] rcu_read_lock_bh include/linux/rcupdate.h:843 [inline] softirqs last enabled at (3180): [] __dev_queue_xmit+0x26b/0x37c0 net/core/dev.c:4282 softirqs last disabled at (3044): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last disabled at (3044): [] rcu_read_lock_bh include/linux/rcupdate.h:843 [inline] softirqs last disabled at (3044): [] __dev_queue_xmit+0x26b/0x37c0 net/core/dev.c:4282 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&htab->lockdep_key#2); lock(&htab->lockdep_key#2); *** DEADLOCK *** 1 lock held by syz.4.7618/29931: #0: ffff8880b8e40cb0 (&cpuctx_mutex){+.+.}-{3:3}, at: perf_event_ctx_lock_nested+0x3b5/0x490 kernel/events/core.c:1309 stack backtrace: CPU: 1 PID: 29931 Comm: syz.4.7618 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: <#DB> dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 lock_acquire+0x2df/0x4a0 kernel/locking/lockdep.c:5653 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 htab_lock_bucket+0x179/0x2f0 kernel/bpf/hashtab.c:166 htab_lru_map_delete_elem+0x1ad/0x780 kernel/bpf/hashtab.c:1438 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+0x522/0x7c0 kernel/events/core.c:10321 __perf_event_overflow+0x448/0x610 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+0x312/0x3f0 kernel/events/core.c:10518 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline] hw_breakpoint_exceptions_notify+0x152/0x470 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_strnlen_user lib/strnlen_user.c:42 [inline] RIP: 0010:strnlen_user+0x15f/0x240 lib/strnlen_user.c:113 Code: df 49 fd eb 49 4d 01 e7 b8 08 00 00 00 4c 29 e0 49 89 c4 bf 09 00 00 00 4c 89 fe e8 fb e2 49 fd 49 83 ff 09 72 5f 4f 8b 2c 26 <49> 8d 44 2d 00 49 f7 d5 49 21 dd 49 21 c5 75 0f e8 fc de 49 fd 49 RSP: 0018:ffffc90004acfbc0 EFLAGS: 00040212 RAX: ffffffff84389575 RBX: 8080808080808080 RCX: ffff88805d040000 RDX: 0000000000000002 RSI: 0000000000000f88 RDI: 0000000000000009 RBP: fefefefefefefeff R08: ffff88805d040000 R09: 000000000000000c R10: 00000000c008240a R11: 0000000000000002 R12: 0000000000000080 R13: cd282f8c5425c92b R14: 0000200000000280 R15: 0000000000000f88 strndup_user+0x1b/0x150 mm/util.c:225 perf_event_set_filter kernel/events/core.c:10912 [inline] _perf_ioctl kernel/events/core.c:5789 [inline] perf_ioctl+0x59b/0x2420 kernel/events/core.c:5860 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 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: 0033:0x7f0c2bf9c819 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:00007f0c2ce11028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f0c2c215fa0 RCX: 00007f0c2bf9c819 RDX: 0000200000000280 RSI: 0000000040082406 RDI: 000000000000000e RBP: 00007f0c2c032c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0c2c216038 R14: 00007f0c2c215fa0 R15: 00007ffd121bb5b8 ---------------- Code disassembly (best guess): 0: df 49 fd fisttps -0x3(%rcx) 3: eb 49 jmp 0x4e 5: 4d 01 e7 add %r12,%r15 8: b8 08 00 00 00 mov $0x8,%eax d: 4c 29 e0 sub %r12,%rax 10: 49 89 c4 mov %rax,%r12 13: bf 09 00 00 00 mov $0x9,%edi 18: 4c 89 fe mov %r15,%rsi 1b: e8 fb e2 49 fd call 0xfd49e31b 20: 49 83 ff 09 cmp $0x9,%r15 24: 72 5f jb 0x85 26: 4f 8b 2c 26 mov (%r14,%r12,1),%r13 * 2a: 49 8d 44 2d 00 lea 0x0(%r13,%rbp,1),%rax <-- trapping instruction 2f: 49 f7 d5 not %r13 32: 49 21 dd and %rbx,%r13 35: 49 21 c5 and %rax,%r13 38: 75 0f jne 0x49 3a: e8 fc de 49 fd call 0xfd49df3b 3f: 49 rex.WB