# CVE-2023-54177: quota: fix warning in dqgrab()

> A null pointer dereference in the Linux kernel quota subsystem allows local attackers to cause a system crash via race conditions during filesystem reconfiguration.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Dec 2025
- **Updated:** 23 May 2026
- **Also known as:** BELL-CVE-2023-54177, DEBIAN-CVE-2023-54177, GHSA-f7wq-xf7h-wrxp, UBUNTU-CVE-2023-54177

## What is CVE-2023-54177?

CVE-2023-54177 is a vulnerability in Linux, published on 30 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

quota: fix warning in dqgrab()

There's issue as follows when do fault injection:
WARNING: CPU: 1 PID: 14870 at include/linux/quotaops.h:51 dquot_disable+0x13b7/0x18c0
Modules linked in:
CPU: 1 PID: 14870 Comm: fsconfig Not tainted 6.3.0-next-20230505-00006-g5107a9c821af-dirty #541
RIP: 0010:dquot_disable+0x13b7/0x18c0
RSP: 0018:ffffc9000acc79e0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88825e41b980
RDX: 0000000000000000 RSI: ffff88825e41b980 RDI: 0000000000000002
RBP: ffff888179f68000 R08: ffffffff82087ca7 R09: 0000000000000000
R10: 0000000000000001 R11: ffffed102f3ed026 R12: ffff888179f68130
R13: ffff888179f68110 R14: dffffc0000000000 R15: ffff888179f68118
FS:  00007f450a073740(0000) GS:ffff88882fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe96f2efd8 CR3: 000000025c8ad000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dquot_load_quota_sb+0xd53/0x1060
 dquot_resume+0x172/0x230
 ext4_reconfigure+0x1dc6/0x27b0
 reconfigure_super+0x515/0xa90
 __x64_sys_fsconfig+0xb19/0xd20
 do_syscall_64+0x39/0xb0
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Above issue may happens as follows:
ProcessA              ProcessB                    ProcessC
sys_fsconfig
  vfs_fsconfig_locked
   reconfigure_super
     ext4_remount
      dquot_suspend -> suspend all type quota

                 sys_fsconfig
                  vfs_fsconfig_locked
                    reconfigure_super
                     ext4_remount
                      dquot_resume
                       ret = dquot_load_quota_sb
                        add_dquot_ref
                                           do_open  -> open file O_RDWR
                                            vfs_open
                                             do_dentry_open
                                              get_write_access
                                               atomic_inc_unless_negative(&inode->i_writecount)
                                              ext4_file_open
                                               dquot_file_open
                                                dquot_initialize
                                                  __dquot_initialize
                                                   dqget
						    atomic_inc(&dquot->dq_count);

                          __dquot_initialize
                           __dquot_initialize
                            dqget
                             if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
                               ext4_acquire_dquot
			        -> Return error DQ_ACTIVE_B flag isn't set
                         dquot_disable
			  invalidate_dquots
			   if (atomic_read(&dquot->dq_count))
	                    dqgrab
			     WARN_ON_ONCE(!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
	                      -> Trigger warning

In the above scenario, 'dquot->dq_flags' has no DQ_ACTIVE_B is normal when
dqgrab().
To solve above issue just replace the dqgrab() use in invalidate_dquots() with
atomic_inc(&dquot->dq_count).

## Which versions are affected by CVE-2023-54177?


## How do I fix CVE-2023-54177?

Apply the vendor's patch.

## Is CVE-2023-54177 being exploited?

There is no known exploitation of CVE-2023-54177 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54177 and fix it if it is affected.

What it is: CVE-2023-54177 is a vulnerability in Linux, published on 30 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-54177 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-54177/ (Markdown: https://insights.sbomify.com/CVE-2023-54177/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54177
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54177
- OSV: https://osv.dev/vulnerability/CVE-2023-54177

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54177/
Summaries are generated and may contain mistakes; the official description above is the record.