Re: [syzbot] [usb?] BUG: unable to handle kernel paging request in ioread32

[Aleksandr Nogikh]

#syz invalid

See the discussion at
https://lore.kernel.org/all/6a88012e.dbb3a75c.13dd47.0007.GAE@xxxxxxxxxx/T/

On Thu, Aug 6, 2026 at 12:43 AM syzbot
<syzbot+97999b836ee62ddb0181@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    848acc8ffe1b Merge tag 'fsverity-for-linus' of git://git.k..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1209b649580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
> dashboard link: https://syzkaller.appspot.com/bug?extid=97999b836ee62ddb0181
> compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15febe32580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=145813b9580000
>
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-848acc8f.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/6fb497cc0c8d/vmlinux-848acc8f.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/663ccee34982/bzImage-848acc8f.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+97999b836ee62ddb0181@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> BUG: unable to handle page fault for address: 00000000000556e0
> #PF: supervisor read access in kernel mode
> #PF: error_code(0x0000) - not-present page
> PGD 275ae067 P4D 275ae067 PUD 0
> Oops: Oops: 0000 [#1] SMP KASAN NOPTI
> CPU: 2 UID: 0 PID: 5940 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
> RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline]
> RIP: 0010:ioread32+0x87/0xc0 lib/iomap.c:99
> Code: 2d 0e 3b 5a 0a 31 ff 89 ee e8 55 f0 e3 fc 85 ed 75 28 e8 dc f5 e3 fc bb ff ff ff ff 89 d8 5b 5d e9 ce 03 98 06 e8 c9 f5 e3 fc <8b> 1b e8 c2 f5 e3 fc 89 d8 5b 5d c3 cc cc cc cc e8 b4 f5 e3 fc 83
> RSP: 0018:ffffc90004c878d0 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: 00000000000556e0 RCX: ffffffff85266eab
> RDX: ffff88803214a540 RSI: ffffffff85266f17 RDI: ffff88803214a540
> RBP: ffff888055c95c38 R08: 0000000000000007 R09: 000000000003ffff
> R10: 00000000000556e0 R11: 0000000000000000 R12: 1ffff92000990f29
> R13: ffff88802323a0d0 R14: ffff888055c95c80 R15: ffffc90004c87968
> FS:  000055557cf64500(0000) GS:ffff8880d5fd8000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000000556e0 CR3: 0000000058784000 CR4: 0000000000352ef0
> Call Trace:
>  <TASK>
>  nhi_probe+0xdc/0x8f0 drivers/thunderbolt/nhi.c:1198
>  nhi_pci_probe+0x322/0x5a0 drivers/thunderbolt/pci.c:479
>  local_pci_probe+0xdd/0x1b0 drivers/pci/pci-driver.c:332
>  pci_call_probe+0x176/0x800 drivers/pci/pci-driver.c:394
>  __pci_device_probe drivers/pci/pci-driver.c:455 [inline]
>  pci_device_probe+0x1cd/0x370 drivers/pci/pci-driver.c:489
>  call_driver_probe drivers/base/dd.c:628 [inline]
>  really_probe+0x241/0xa60 drivers/base/dd.c:706
>  __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
>  device_driver_attach+0xd1/0x220 drivers/base/dd.c:1203
>  bind_store+0xf4/0x190 drivers/base/bus.c:267
>  drv_attr_store+0x74/0xb0 drivers/base/bus.c:125
>  sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
>  kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
>  new_sync_write fs/read_write.c:595 [inline]
>  vfs_write+0x6ac/0x1050 fs/read_write.c:687
>  ksys_write+0x12a/0x250 fs/read_write.c:739
>  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
>  do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
>  entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7fb04af9e019
> 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:00007fff5f802b58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> RAX: ffffffffffffffda RBX: 00007fb04b225fa0 RCX: 00007fb04af9e019
> RDX: 000000000000000d RSI: 0000200000000240 RDI: 0000000000000005
> RBP: 00007fb04b03500c R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007fb04b225fac R14: 00007fb04b225fa0 R15: 00007fb04b225fa0
>  </TASK>
> Modules linked in:
> CR2: 00000000000556e0
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:readl arch/x86/include/asm/io.h:59 [inline]
> RIP: 0010:ioread32+0x87/0xc0 lib/iomap.c:99
> Code: 2d 0e 3b 5a 0a 31 ff 89 ee e8 55 f0 e3 fc 85 ed 75 28 e8 dc f5 e3 fc bb ff ff ff ff 89 d8 5b 5d e9 ce 03 98 06 e8 c9 f5 e3 fc <8b> 1b e8 c2 f5 e3 fc 89 d8 5b 5d c3 cc cc cc cc e8 b4 f5 e3 fc 83
> RSP: 0018:ffffc90004c878d0 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: 00000000000556e0 RCX: ffffffff85266eab
> RDX: ffff88803214a540 RSI: ffffffff85266f17 RDI: ffff88803214a540
> RBP: ffff888055c95c38 R08: 0000000000000007 R09: 000000000003ffff
> R10: 00000000000556e0 R11: 0000000000000000 R12: 1ffff92000990f29
> R13: ffff88802323a0d0 R14: ffff888055c95c80 R15: ffffc90004c87968
> FS:  000055557cf64500(0000) GS:ffff8880d5fd8000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000000556e0 CR3: 0000000058784000 CR4: 0000000000352ef0
> ----------------
> Code disassembly (best guess):
>    0:   2d 0e 3b 5a 0a          sub    $0xa5a3b0e,%eax
>    5:   31 ff                   xor    %edi,%edi
>    7:   89 ee                   mov    %ebp,%esi
>    9:   e8 55 f0 e3 fc          call   0xfce3f063
>    e:   85 ed                   test   %ebp,%ebp
>   10:   75 28                   jne    0x3a
>   12:   e8 dc f5 e3 fc          call   0xfce3f5f3
>   17:   bb ff ff ff ff          mov    $0xffffffff,%ebx
>   1c:   89 d8                   mov    %ebx,%eax
>   1e:   5b                      pop    %rbx
>   1f:   5d                      pop    %rbp
>   20:   e9 ce 03 98 06          jmp    0x69803f3
>   25:   e8 c9 f5 e3 fc          call   0xfce3f5f3
> * 2a:   8b 1b                   mov    (%rbx),%ebx <-- trapping instruction
>   2c:   e8 c2 f5 e3 fc          call   0xfce3f5f3
>   31:   89 d8                   mov    %ebx,%eax
>   33:   5b                      pop    %rbx
>   34:   5d                      pop    %rbp
>   35:   c3                      ret
>   36:   cc                      int3
>   37:   cc                      int3
>   38:   cc                      int3
>   39:   cc                      int3
>   3a:   e8 b4 f5 e3 fc          call   0xfce3f5f3
>   3f:   83                      .byte 0x83
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.
>
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>
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>
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>
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>
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