Oops: general protection fault, probably for non-canonical address 0xdffffc0000000060: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000300-0x0000000000000307]
CPU: 0 UID: 0 PID: 26428 Comm: syz.0.4502 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:strcmp+0x5b/0xb0 lib/string.c:284
Code: fa 48 c1 e8 03 83 e2 07 42 0f b6 04 28 38 d0 7f 04 84 c0 75 58 48 89 f0 48 89 f2 0f b6 6b ff 4c 8d 66 01 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 04 84 c0 75 2c 41 3a 6c 24 ff 74 ae 19 c0
RSP: 0018:ffffc900000079b8 EFLAGS: 00010046
RAX: 0000000000000060 RBX: ffffffff878982c1 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000300 RDI: ffffffff878982c0
RBP: 0000000000000026 R08: 0000000000000001 R09: 0000000000000001
R10: ffff88811476800b R11: 0000000000000001 R12: 0000000000000301
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8ea36720
FS:  0000000000000000(0000) GS:ffff888268ea4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f324bc002c0 CR3: 000000013ec0a000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 count_matching_names kernel/locking/lockdep.c:878 [inline]
 register_lock_class+0x26d/0x4c0 kernel/locking/lockdep.c:1344
 __lock_acquire+0x9f/0x1ce0 kernel/locking/lockdep.c:5112
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
 complete_with_flags kernel/sched/completion.c:25 [inline]
 complete+0x1d/0x200 kernel/sched/completion.c:52
 transfer drivers/usb/gadget/udc/dummy_hcd.c:1523 [inline]
 dummy_timer+0x1c3e/0x3a00 drivers/usb/gadget/udc/dummy_hcd.c:1979
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858
 handle_softirqs+0x205/0x8d0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: f9 3c 0b 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 e2 08 46 09 0f 82 74 02 00 00 8b 35 5a 15 46 09 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 f9 f8 3c 0b 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc9000afd74f0 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff892c89a0 RCX: 00000000feabdeab
RDX: 0000000000000000 RSI: ffffffff88c6719d RDI: ffffffff87897640
RBP: 0000000000000002 R08: 1d9f0e8120da8f20 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 page_table_check_clear+0x190/0x740 mm/page_table_check.c:77
 __page_table_check_pte_clear+0xf1/0x100 mm/page_table_check.c:154
 page_table_check_pte_clear include/linux/page_table_check.h:51 [inline]
 ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1270 [inline]
 get_and_clear_full_ptes include/linux/pgtable.h:725 [inline]
 zap_present_folio_ptes mm/memory.c:1627 [inline]
 zap_present_ptes mm/memory.c:1709 [inline]
 do_zap_pte_range mm/memory.c:1810 [inline]
 zap_pte_range mm/memory.c:1854 [inline]
 zap_pmd_range mm/memory.c:1946 [inline]
 zap_pud_range mm/memory.c:1975 [inline]
 zap_p4d_range mm/memory.c:1996 [inline]
 unmap_page_range+0x1e6f/0x3660 mm/memory.c:2017
 unmap_single_vma.constprop.0+0x153/0x240 mm/memory.c:2060
 unmap_vmas+0x218/0x470 mm/memory.c:2104
 exit_mmap+0x1b2/0xb90 mm/mmap.c:1280
 __mmput kernel/fork.c:1133 [inline]
 mmput+0xdb/0x430 kernel/fork.c:1156
 exit_mm kernel/exit.c:582 [inline]
 do_exit+0x7c7/0x2bf0 kernel/exit.c:954
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1107
 get_signal+0x2671/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x76/0xe0 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x40f/0x4d0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa482041785
Code: Unable to access opcode bytes at 0x7fa48204175b.
RSP: 002b:00007fff6829a0a0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: 0000000000000000 RBX: 00007fa482265fa0 RCX: 00007fa482041785
RDX: 00007fff6829a0e0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa482267da0 R08: 0000000000000000 R09: 00007fa481e78000
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000002583ca
R13: 00007fa482266270 R14: ffffffffffffffff R15: 00007fff6829a220
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:strcmp+0x5b/0xb0 lib/string.c:284
Code: fa 48 c1 e8 03 83 e2 07 42 0f b6 04 28 38 d0 7f 04 84 c0 75 58 48 89 f0 48 89 f2 0f b6 6b ff 4c 8d 66 01 48 c1 e8 03 83 e2 07 <42> 0f b6 04 28 38 d0 7f 04 84 c0 75 2c 41 3a 6c 24 ff 74 ae 19 c0
RSP: 0018:ffffc900000079b8 EFLAGS: 00010046
RAX: 0000000000000060 RBX: ffffffff878982c1 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000300 RDI: ffffffff878982c0
RBP: 0000000000000026 R08: 0000000000000001 R09: 0000000000000001
R10: ffff88811476800b R11: 0000000000000001 R12: 0000000000000301
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8ea36720
FS:  0000000000000000(0000) GS:ffff888268ea4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f324bc002c0 CR3: 000000013ec0a000 CR4: 00000000003506f0
----------------
Code disassembly (best guess):
   0:	fa                   	cli
   1:	48 c1 e8 03          	shr    $0x3,%rax
   5:	83 e2 07             	and    $0x7,%edx
   8:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
   d:	38 d0                	cmp    %dl,%al
   f:	7f 04                	jg     0x15
  11:	84 c0                	test   %al,%al
  13:	75 58                	jne    0x6d
  15:	48 89 f0             	mov    %rsi,%rax
  18:	48 89 f2             	mov    %rsi,%rdx
  1b:	0f b6 6b ff          	movzbl -0x1(%rbx),%ebp
  1f:	4c 8d 66 01          	lea    0x1(%rsi),%r12
  23:	48 c1 e8 03          	shr    $0x3,%rax
  27:	83 e2 07             	and    $0x7,%edx
* 2a:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax <-- trapping instruction
  2f:	38 d0                	cmp    %dl,%al
  31:	7f 04                	jg     0x37
  33:	84 c0                	test   %al,%al
  35:	75 2c                	jne    0x63
  37:	41 3a 6c 24 ff       	cmp    -0x1(%r12),%bpl
  3c:	74 ae                	je     0xffffffec
  3e:	19 c0                	sbb    %eax,%eax