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

fsverity: reject FS_IOC_ENABLE_VERITY on mode 3 fds

Commit 56124d6c87fd ("fsverity: support enabling with tree block size <
PAGE_SIZE") changed FS_IOC_ENABLE_VERITY to use __kernel_read() to read
the file's data, instead of direct pagecache accesses.

An unintended consequence of this is that the
'WARN_ON_ONCE(!(file->f_mode & FMODE_READ))' in __kernel_read() became
reachable by fuzz tests. This happens if FS_IOC_ENABLE_VERITY is called
on a fd opened with access mode 3, which means "ioctl access only".

Arguably, FS_IOC_ENABLE_VERITY should work on ioctl-only fds. But
ioctl-only fds are a weird Linux extension that is rarely used and that
few people even know about. (The documentation for FS_IOC_ENABLE_VERITY
even specifically says it requires O_RDONLY.) It's probably not
worthwhile to make the ioctl internally open a new fd just to handle
this case. Thus, just reject the ioctl on such fds for now.
Advisories
Source ID Title
EUVD EUVD EUVD-2023-59804 In the Linux kernel, the following vulnerability has been resolved: fsverity: reject FS_IOC_ENABLE_VERITY on mode 3 fds Commit 56124d6c87fd ("fsverity: support enabling with tree block size < PAGE_SIZE") changed FS_IOC_ENABLE_VERITY to use __kernel_read() to read the file's data, instead of direct pagecache accesses. An unintended consequence of this is that the 'WARN_ON_ONCE(!(file->f_mode & FMODE_READ))' in __kernel_read() became reachable by fuzz tests. This happens if FS_IOC_ENABLE_VERITY is called on a fd opened with access mode 3, which means "ioctl access only". Arguably, FS_IOC_ENABLE_VERITY should work on ioctl-only fds. But ioctl-only fds are a weird Linux extension that is rarely used and that few people even know about. (The documentation for FS_IOC_ENABLE_VERITY even specifically says it requires O_RDONLY.) It's probably not worthwhile to make the ioctl internally open a new fd just to handle this case. Thus, just reject the ioctl on such fds for now.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 02 Dec 2025 19:15:00 +0000

Type Values Removed Values Added
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:6.3:*:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

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'}


Wed, 17 Sep 2025 11:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Vendors & Products Linux
Linux linux Kernel

Wed, 17 Sep 2025 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate


Mon, 15 Sep 2025 14:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: fsverity: reject FS_IOC_ENABLE_VERITY on mode 3 fds Commit 56124d6c87fd ("fsverity: support enabling with tree block size < PAGE_SIZE") changed FS_IOC_ENABLE_VERITY to use __kernel_read() to read the file's data, instead of direct pagecache accesses. An unintended consequence of this is that the 'WARN_ON_ONCE(!(file->f_mode & FMODE_READ))' in __kernel_read() became reachable by fuzz tests. This happens if FS_IOC_ENABLE_VERITY is called on a fd opened with access mode 3, which means "ioctl access only". Arguably, FS_IOC_ENABLE_VERITY should work on ioctl-only fds. But ioctl-only fds are a weird Linux extension that is rarely used and that few people even know about. (The documentation for FS_IOC_ENABLE_VERITY even specifically says it requires O_RDONLY.) It's probably not worthwhile to make the ioctl internally open a new fd just to handle this case. Thus, just reject the ioctl on such fds for now.
Title fsverity: reject FS_IOC_ENABLE_VERITY on mode 3 fds
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-09-15T14:04:06.075Z

Reserved: 2025-09-15T13:59:19.064Z

Link: CVE-2023-53172

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2025-09-15T14:15:39.057

Modified: 2025-12-02T19:09:53.717

Link: CVE-2023-53172

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-09-15T00:00:00Z

Links: CVE-2023-53172 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-09-17T10:08:10Z