syzbot


inconsistent lock state in htab_map_delete_elem

Status: upstream: reported C repro on 2025/11/29 21:34
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+33a29bcf8af10436a5c7@syzkaller.appspotmail.com
First crash: 112d, last: 51m
Fix bisection: failed (error log, bisect log)
  
Bug presence (2)
Date Name Commit Repro Result
2025/11/30 linux-5.15.y (ToT) cc5ec8769306 C [report] inconsistent lock state in htab_map_delete_elem
2025/11/30 upstream (ToT) 6bda50f4333f C Didn't crash
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/12/21 14:54 12m retest repro linux-5.15.y report log
Fix bisection attempts (3)
Created Duration User Patch Repo Result
2026/02/21 09:29 1m fix candidate upstream error job log
2026/01/22 08:43 1m fix candidate upstream error job log
2026/01/21 20:51 0m bisect fix linux-5.15.y error job log

Sample crash report:
================================
WARNING: inconsistent lock state
syzkaller #0 Not tainted
--------------------------------
inconsistent {INITIAL USE} -> {IN-NMI} usage.
syz.0.17/4312 [HC1[1]:SC0[0]:HE0:SE1] takes:
ffff888025149020 (&htab->lockdep_key){....}-{2:2}, at: htab_lock_bucket kernel/bpf/hashtab.c:183 [inline]
ffff888025149020 (&htab->lockdep_key){....}-{2:2}, at: htab_map_delete_elem+0x1b2/0x520 kernel/bpf/hashtab.c:1361
{INITIAL USE} state was registered at:
  lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
  __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
  _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
  htab_lock_bucket kernel/bpf/hashtab.c:183 [inline]
  htab_map_delete_elem+0x1b2/0x520 kernel/bpf/hashtab.c:1361
  bpf_prog_2c29ac5cdc6b1842+0x3a/0x48
  bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
  __bpf_prog_run include/linux/filter.h:628 [inline]
  bpf_prog_run include/linux/filter.h:635 [inline]
  bpf_overflow_handler+0x1c2/0x4a0 kernel/events/core.c:10297
  __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
  perf_bp_event+0x276/0x320 kernel/events/core.c:10484
  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:83 [inline]
  atomic_notifier_call_chain+0x15d/0x280 kernel/notifier.c:198
  notify_die+0x141/0x1a0 kernel/notifier.c:529
  notify_debug+0x20/0x30 arch/x86/kernel/traps.c:872
  exc_debug_user arch/x86/kernel/traps.c:998 [inline]
  noist_exc_debug+0x73/0x120 arch/x86/kernel/traps.c:1035
  asm_exc_debug+0x2f/0x40 arch/x86/include/asm/idtentry.h:642
irq event stamp: 7300
hardirqs last  enabled at (7299): [<ffffffff89bc7401>] syscall_enter_from_user_mode+0x21/0x70 kernel/entry/common.c:113
hardirqs last disabled at (7300): [<ffffffff89bc446e>] exc_debug_kernel arch/x86/kernel/traps.c:893 [inline]
hardirqs last disabled at (7300): [<ffffffff89bc446e>] exc_debug+0x6e/0x130 arch/x86/kernel/traps.c:1029
softirqs last  enabled at (7098): [<ffffffff8186da79>] bpf_prog_load+0x10f9/0x1510 kernel/bpf/syscall.c:2380
softirqs last disabled at (7096): [<ffffffff81853c79>] spin_lock_bh include/linux/spinlock.h:369 [inline]
softirqs last disabled at (7096): [<ffffffff81853c79>] bpf_ksym_add+0x29/0x340 kernel/bpf/core.c:633

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&htab->lockdep_key);
  <Interrupt>
    lock(&htab->lockdep_key);

 *** DEADLOCK ***

no locks held by syz.0.17/4312.

stack backtrace:
CPU: 1 PID: 4312 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <#DB>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 lock_acquire+0x2c3/0x400 kernel/locking/lockdep.c:5614
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
 htab_lock_bucket kernel/bpf/hashtab.c:183 [inline]
 htab_map_delete_elem+0x1b2/0x520 kernel/bpf/hashtab.c:1361
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x48
 bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 bpf_overflow_handler+0x1c2/0x4a0 kernel/events/core.c:10297
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_bp_event+0x276/0x320 kernel/events/core.c:10484
 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:83 [inline]
 atomic_notifier_call_chain+0x15d/0x280 kernel/notifier.c:198
 notify_die+0x141/0x1a0 kernel/notifier.c:529
 notify_debug+0x20/0x30 arch/x86/kernel/traps.c:872
 exc_debug_kernel arch/x86/kernel/traps.c:929 [inline]
 exc_debug+0xcf/0x130 arch/x86/kernel/traps.c:1029
 asm_exc_debug+0x1a/0x40 arch/x86/include/asm/idtentry.h:642
RIP: 0010:copy_user_enhanced_fast_string+0xe/0x40 arch/x86/lib/copy_user_64.S:206
Code: 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 0f 01 cb 83 fa 40 0f 82 70 ff ff ff 89 d1 <f3> a4 31 c0 0f 01 ca c3 90 90 90 90 90 90 90 90 90 90 89 d1 83 f8
RSP: 0018:ffffc90002eafd80 EFLAGS: 00050202
RAX: ffffffff83e3e101 RBX: 0000000000000050 RCX: 000000000000004f
RDX: 0000000000000050 RSI: 0000200000000301 RDI: ffffc90002eafe01
RBP: 0000000000000000 R08: ffffc90002eafe4f R09: 1ffff920005d5fc9
R10: dffffc0000000000 R11: fffff520005d5fca R12: 00007ffffffff000
R13: 0000200000000350 R14: ffffc90002eafe00 R15: 0000200000000300
 </#DB>
 <TASK>
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline]
 _copy_from_user+0xfa/0x170 lib/usercopy.c:23
 copy_from_user include/linux/uaccess.h:192 [inline]
 copy_from_bpfptr_offset include/linux/bpfptr.h:52 [inline]
 copy_from_bpfptr include/linux/bpfptr.h:58 [inline]
 __sys_bpf+0x26d/0x6f0 kernel/bpf/syscall.c:4630
 __do_sys_bpf kernel/bpf/syscall.c:4761 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4759 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0fa0951799
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:00007fffbc8d1468 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f0fa0bcafa0 RCX: 00007f0fa0951799
RDX: 0000000000000050 RSI: 0000200000000300 RDI: 0000000000000000
RBP: 00007f0fa09e7c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0fa0bcafac R14: 00007f0fa0bcafa0 R15: 00007f0fa0bcafa0
 </TASK>
----------------
Code disassembly (best guess):
   0:	89 d1                	mov    %edx,%ecx
   2:	c1 e9 03             	shr    $0x3,%ecx
   5:	83 e2 07             	and    $0x7,%edx
   8:	f3 48 a5             	rep movsq %ds:(%rsi),%es:(%rdi)
   b:	89 d1                	mov    %edx,%ecx
   d:	f3 a4                	rep movsb %ds:(%rsi),%es:(%rdi)
   f:	31 c0                	xor    %eax,%eax
  11:	0f 01 ca             	clac
  14:	c3                   	ret
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	90                   	nop
  1c:	0f 01 cb             	stac
  1f:	83 fa 40             	cmp    $0x40,%edx
  22:	0f 82 70 ff ff ff    	jb     0xffffff98
  28:	89 d1                	mov    %edx,%ecx
* 2a:	f3 a4                	rep movsb %ds:(%rsi),%es:(%rdi) <-- trapping instruction
  2c:	31 c0                	xor    %eax,%eax
  2e:	0f 01 ca             	clac
  31:	c3                   	ret
  32:	90                   	nop
  33:	90                   	nop
  34:	90                   	nop
  35:	90                   	nop
  36:	90                   	nop
  37:	90                   	nop
  38:	90                   	nop
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	89 d1                	mov    %edx,%ecx
  3e:	83                   	.byte 0x83
  3f:	f8                   	clc

Crashes (1037):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/16 23:45 linux-5.15.y 91d48252ad4b 0737c18f .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2025/11/29 21:33 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2025/12/06 04:33 linux-5.15.y cc5ec8769306 d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 19:13 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 18:03 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 17:02 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 15:52 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 14:39 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 14:14 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 12:56 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 11:42 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/22 08:43 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 22:49 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 21:43 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 20:34 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 19:32 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 18:23 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 17:10 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 15:55 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 14:37 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 13:34 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 12:21 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 10:18 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 09:06 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 07:36 linux-5.15.y 91d48252ad4b 5b92003d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 02:55 linux-5.15.y 91d48252ad4b ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/21 01:19 linux-5.15.y 91d48252ad4b ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 23:49 linux-5.15.y 91d48252ad4b ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 22:29 linux-5.15.y 91d48252ad4b ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 21:10 linux-5.15.y 91d48252ad4b ac6f1dff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 14:00 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 12:50 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 10:05 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 08:40 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 06:51 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 05:41 linux-5.15.y 91d48252ad4b 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 01:45 linux-5.15.y 91d48252ad4b bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/20 00:37 linux-5.15.y 91d48252ad4b bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/19 23:05 linux-5.15.y 91d48252ad4b bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/19 10:48 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/19 09:59 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/19 07:57 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/19 06:20 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/19 02:07 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/18 20:43 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
2026/03/18 19:26 linux-5.15.y 91d48252ad4b 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf inconsistent lock state in htab_map_delete_elem
* Struck through repros no longer work on HEAD.