BUG: kernel NULL pointer dereference, address: 0000000000000008
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 8000000057d76067 P4D 8000000057d76067 PUD 2d2ed067 PMD 2d2ee067 PTE 7fffffffffffc0a
Oops: Oops: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 6211 Comm: syz.1.90 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:qlink_to_cache mm/kasan/quarantine.c:131 [inline]
RIP: 0010:qlist_move_cache+0x9d/0xf0 mm/kasan/quarantine.c:303
Code: 48 89 c2 48 c1 e2 06 48 03 15 3f 72 a7 0b 48 8b 42 08 48 89 c1 83 e1 01 48 83 e9 01 48 09 c8 48 21 d0 80 78 33 f5 49 0f 45 c4 <48> 8b 40 08 8b 50 18 48 39 c5 75 92 48 83 3b 00 74 33 48 8b 43 08
RSP: 0018:ffffc9000598fc80 EFLAGS: 00010006
RAX: 0000000000000000 RBX: ffffc9000598fcb8 RCX: ffffffffffffffff
RDX: ffffea0000c8e400 RSI: ffffc9000598fcb8 RDI: ffff888032390001
RBP: ffff88814a09edc0 R08: 0000000000000001 R09: fffff52000b31f85
R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000000
R13: ffffffff9b1c34e0 R14: ffff888032390001 R15: f8f8f8f8f8f8f8f8
FS:  00007f8c89fee6c0(0000) GS:ffff88812437d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 000000007ca26000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 kasan_quarantine_remove_cache+0xf7/0x170 mm/kasan/quarantine.c:370
 kmem_cache_destroy mm/slab_common.c:567 [inline]
 kmem_cache_destroy+0x6b/0x180 mm/slab_common.c:527
 mon_text_release+0x267/0x3b0 drivers/usb/mon/mon_text.c:677
 full_proxy_release+0xc0/0x140 fs/debugfs/file.c:427
 __fput+0x3ff/0xb50 fs/file_table.c:510
 task_work_run+0x150/0x240 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
 exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x6f2/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c8bd9cdd9
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:00007f8c89fee028 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f8c8c015fa0 RCX: 00007f8c8bd9cdd9
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000002
RBP: 00007f8c8be32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8c8c016038 R14: 00007f8c8c015fa0 R15: 00007ffe376d6f48
 </TASK>
Modules linked in:
CR2: 0000000000000008
---[ end trace 0000000000000000 ]---
RIP: 0010:qlink_to_cache mm/kasan/quarantine.c:131 [inline]
RIP: 0010:qlist_move_cache+0x9d/0xf0 mm/kasan/quarantine.c:303
Code: 48 89 c2 48 c1 e2 06 48 03 15 3f 72 a7 0b 48 8b 42 08 48 89 c1 83 e1 01 48 83 e9 01 48 09 c8 48 21 d0 80 78 33 f5 49 0f 45 c4 <48> 8b 40 08 8b 50 18 48 39 c5 75 92 48 83 3b 00 74 33 48 8b 43 08
RSP: 0018:ffffc9000598fc80 EFLAGS: 00010006
RAX: 0000000000000000 RBX: ffffc9000598fcb8 RCX: ffffffffffffffff
RDX: ffffea0000c8e400 RSI: ffffc9000598fcb8 RDI: ffff888032390001
RBP: ffff88814a09edc0 R08: 0000000000000001 R09: fffff52000b31f85
R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000000
R13: ffffffff9b1c34e0 R14: ffff888032390001 R15: f8f8f8f8f8f8f8f8
FS:  00007f8c89fee6c0(0000) GS:ffff88812437d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 000000007ca26000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	48 89 c2             	mov    %rax,%rdx
   3:	48 c1 e2 06          	shl    $0x6,%rdx
   7:	48 03 15 3f 72 a7 0b 	add    0xba7723f(%rip),%rdx        # 0xba7724d
   e:	48 8b 42 08          	mov    0x8(%rdx),%rax
  12:	48 89 c1             	mov    %rax,%rcx
  15:	83 e1 01             	and    $0x1,%ecx
  18:	48 83 e9 01          	sub    $0x1,%rcx
  1c:	48 09 c8             	or     %rcx,%rax
  1f:	48 21 d0             	and    %rdx,%rax
  22:	80 78 33 f5          	cmpb   $0xf5,0x33(%rax)
  26:	49 0f 45 c4          	cmovne %r12,%rax
* 2a:	48 8b 40 08          	mov    0x8(%rax),%rax <-- trapping instruction
  2e:	8b 50 18             	mov    0x18(%rax),%edx
  31:	48 39 c5             	cmp    %rax,%rbp
  34:	75 92                	jne    0xffffffc8
  36:	48 83 3b 00          	cmpq   $0x0,(%rbx)
  3a:	74 33                	je     0x6f
  3c:	48 8b 43 08          	mov    0x8(%rbx),%rax