CVE-2025-21721

nilfs2: handle errors that nilfs_prepare_chunk() may return

Published Feb 27, 2025 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

nilfs2: handle errors that nilfs_prepare_chunk() may return

Patch series "nilfs2: fix issues with rename operations".

This series fixes BUG_ON check failures reported by syzbot around rename
operations, and a minor behavioral issue where the mtime of a child
directory changes when it is renamed instead of moved.


This patch (of 2):

The directory manipulation routines nilfs_set_link() and
nilfs_delete_entry() rewrite the directory entry in the folio/page
previously read by nilfs_find_entry(), so error handling is omitted on the
assumption that nilfs_prepare_chunk(), which prepares the buffer for
rewriting, will always succeed for these. And if an error is returned, it
triggers the legacy BUG_ON() checks in each routine.

This assumption is wrong, as proven by syzbot: the buffer layer called by
nilfs_prepare_chunk() may call nilfs_get_block() if necessary, which may
fail due to metadata corruption or other reasons. This has been there all
along, but improved sanity checks and error handling may have made it more
reproducible in fuzzing tests.

Fix this issue by adding missing error paths in nilfs_set_link(),
nilfs_delete_entry(), and their caller nilfs_rename().

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4178-1 linux security update
Debian DLA Debian DLA DLA-4193-1 linux-6.1 security update
Debian DSA Debian DSA DSA-5900-1 linux security update
EUVD EUVD EUVD-2025-5232 In the Linux kernel, the following vulnerability has been resolved: nilfs2: handle errors that nilfs_prepare_chunk() may return Patch series "nilfs2: fix issues with rename operations". This series fixes BUG_ON check failures reported by syzbot around rename operations, and a minor behavioral issue where the mtime of a child directory changes when it is renamed instead of moved. This patch (of 2): The directory manipulation routines nilfs_set_link() and nilfs_delete_entry() rewrite the directory entry in the folio/page previously read by nilfs_find_entry(), so error handling is omitted on the assumption that nilfs_prepare_chunk(), which prepares the buffer for rewriting, will always succeed for these. And if an error is returned, it triggers the legacy BUG_ON() checks in each routine. This assumption is wrong, as proven by syzbot: the buffer layer called by nilfs_prepare_chunk() may call nilfs_get_block() if necessary, which may fail due to metadata corruption or other reasons. This has been there all along, but improved sanity checks and error handling may have made it more reproducible in fuzzing tests. Fix this issue by adding missing error paths in nilfs_set_link(), nilfs_delete_entry(), and their caller nilfs_rename().
Ubuntu USN Ubuntu USN USN-7510-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-4 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-5 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-6 Linux kernel (AWS FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-7 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7510-8 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7511-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7511-2 Linux kernel (GCP FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7511-3 Linux kernel (GKE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7512-1 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-2 Linux kernel (GCP FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-4 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-5 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-6 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-7 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-8 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7516-9 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7517-1 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7517-2 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7517-3 Linux kernel (BlueField) vulnerabilities
Ubuntu USN Ubuntu USN USN-7518-1 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7521-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7521-2 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7521-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7539-1 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7540-1 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7593-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7602-1 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7640-1 Linux kernel (IoT) vulnerabilities
Ubuntu USN Ubuntu USN USN-7651-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7651-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7651-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7651-4 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7651-5 Linux kernel (Raspberry Pi Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7651-6 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7652-1 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7653-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7737-1 Linux kernel (Azure) vulnerabilities
History
Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses CWE-617
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: nilfs2: handle errors that nilfs_prepare_chunk() may return Patch series "nilfs2: fix issues with rename operations". This series fixes BUG_ON check failures reported by syzbot around rename operations, and a minor behavioral issue where the mtime of a child directory changes when it is renamed instead of moved. This patch (of 2): The directory manipulation routines nilfs_set_link() and nilfs_delete_entry() rewrite the directory entry in the folio/page previously read by nilfs_find_entry(), so error handling is omitted on the assumption that nilfs_prepare_chunk(), which prepares the buffer for rewriting, will always succeed for these. And if an error is returned, it triggers the legacy BUG_ON() checks in each routine. This assumption is wrong, as proven by syzbot: the buffer layer called by nilfs_prepare_chunk() may call nilfs_get_block() if necessary, which may fail due to metadata corruption or other reasons. This has been there all along, but improved sanity checks and error handling may have made it more reproducible in fuzzing tests. Fix this issue by adding missing error paths in nilfs_set_link(), nilfs_delete_entry(), and their caller nilfs_rename().
Title nilfs2: handle errors that nilfs_prepare_chunk() may return
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
May 11, 2026, 9:05 PM
Reserved
Dec 29, 2024, 8:45 AM
Status
Modified
Published
Feb 27, 2025, 2:15 AM
Modified
Jun 17, 2026, 8:44 AM
Severity
Low
Public date
Feb 27, 2025, 12:00 AM