---
id: CVE-2023-53576
title: 'null_blk: Always check queue mode setting from configfs'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  null_blk: Always check queue mode setting from configfs

  Make sure to check device queue mode in the null_validate_conf() and
  return error for NULL_Q_RQ as we don't all…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b <
    e732a266b973cd4e115e2cc2ea5007119e8a7fbc
  - >-
    Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b <
    35e304dbcefa95237a3d6f94c007bfb10f012b17
  - >-
    Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b <
    fd35b7bb6d5a329c427924886949ab51f210200a
  - >-
    Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b <
    651260e563d9f50827dac496dc8a0b9b23d5db1a
  - >-
    Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b <
    63f8793ee60513a09f110ea460a6ff2c33811cdb
  - Linux 4.20
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T20:24:17.398915Z'
published: '2025-10-04'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T20:31:15.450Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2023-53576'
references:
  - url: 'https://git.kernel.org/stable/c/e732a266b973cd4e115e2cc2ea5007119e8a7fbc'
  - url: 'https://git.kernel.org/stable/c/35e304dbcefa95237a3d6f94c007bfb10f012b17'
  - url: 'https://git.kernel.org/stable/c/fd35b7bb6d5a329c427924886949ab51f210200a'
  - url: 'https://git.kernel.org/stable/c/651260e563d9f50827dac496dc8a0b9b23d5db1a'
  - url: 'https://git.kernel.org/stable/c/63f8793ee60513a09f110ea460a6ff2c33811cdb'
tags:
  - cve.org
epss: 0.00148
epssPercentile: 0.04029
ingestedAt: '2026-11-05T22:38:31.811Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

null_blk: Always check queue mode setting from configfs

Make sure to check device queue mode in the null_validate_conf() and
return error for NULL_Q_RQ as we don't allow legacy I/O path, without
this patch we get OOPs when queue mode is set to 1 from configfs,
following are repro steps :-

modprobe null_blk nr_devices=0
mkdir config/nullb/nullb0
echo 1 > config/nullb/nullb0/memory_backed
echo 4096 > config/nullb/nullb0/blocksize
echo 20480 > config/nullb/nullb0/size
echo 1 > config/nullb/nullb0/queue_mode
echo 1 > config/nullb/nullb0/power

Entering kdb (current=0xffff88810acdd080, pid 2372) on processor 42 Oops: (null)
due to oops @ 0xffffffffc041c329
CPU: 42 PID: 2372 Comm: sh Tainted: G           O     N 6.3.0-rc5lblk+ #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:null_add_dev.part.0+0xd9/0x720 [null_blk]
Code: 01 00 00 85 d2 0f 85 a1 03 00 00 48 83 bb 08 01 00 00 00 0f 85 f7 03 00 00 80 bb 62 01 00 00 00 48 8b 75 20 0f 85 6d 02 00 00 <48> 89 6e 60 48 8b 75 20 bf 06 00 00 00 e8 f5 37 2c c1 48 8b 75 20
RSP: 0018:ffffc900052cbde0 EFLAGS: 00010246
RAX: 0000000000000001 RBX: ffff88811084d800 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888100042e00
RBP: ffff8881053d8200 R08: ffffc900052cbd68 R09: ffff888105db2000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000002
R13: ffff888104765200 R14: ffff88810eec1748 R15: ffff88810eec1740
FS:  00007fd445fd1740(0000) GS:ffff8897dfc80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000060 CR3: 0000000166a00000 CR4: 0000000000350ee0
DR0: ffffffff8437a488 DR1: ffffffff8437a489 DR2: ffffffff8437a48a
DR3: ffffffff8437a48b DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 nullb_device_power_store+0xd1/0x120 [null_blk]
 configfs_write_iter+0xb4/0x120
 vfs_write+0x2ba/0x3c0
 ksys_write+0x5f/0xe0
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7fd4460c57a7
Code: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007ffd3792a4a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fd4460c57a7
RDX: 0000000000000002 RSI: 000055b43c02e4c0 RDI: 0000000000000001
RBP: 000055b43c02e4c0 R08: 000000000000000a R09: 00007fd44615b4e0
R10: 00007fd44615b3e0 R11: 0000000000000246 R12: 0000000000000002
R13: 00007fd446198520 R14: 0000000000000002 R15: 00007fd446198700
 </TASK>

## Affected

- `Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b < e732a266b973cd4e115e2cc2ea5007119e8a7fbc`
- `Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b < 35e304dbcefa95237a3d6f94c007bfb10f012b17`
- `Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b < fd35b7bb6d5a329c427924886949ab51f210200a`
- `Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b < 651260e563d9f50827dac496dc8a0b9b23d5db1a`
- `Linux >= e50b1e327aeb4b224364aa6f85c1713ff8b3654b < 63f8793ee60513a09f110ea460a6ff2c33811cdb`
- `Linux 4.20`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.