CVE-2024-57924: fs: relax assertions on failure to encode file handles

Medium severity · published Jan 19, 2025

CVE-2024-57924

fs: relax assertions on failure to encode file handles

5.5

CVSS

0.3%

EPSS

On KEV

Description

In the Linux kernel, the following vulnerability has been resolved: fs: relax assertions on failure to encode file handles Encoding file handles is usually performed by a filesystem >encode_fh() method that may fail for various reasons. The legacy users of exportfs_encode_fh(), namely, nfsd and name_to_handle_at(2) syscall are ready to cope with the possibility of failure to encode a file handle. There are a few other users of exportfs_encode_{fh,fid}() that currently have a WARN_ON() assertion when ->encode_fh() fails. Relax those assertions because they are wrong. The second linked bug report states commit 16aac5ad1fa9 ("ovl: support encoding non-decodable file handles") in v6.6 as the regressing commit, but this is not accurate. The aforementioned commit only increases the chances of the assertion and allows triggering the assertion with the reproducer using overlayfs, inotify and drop_caches. Triggering this assertion was always possible with other filesystems and other reasons of ->encode_fh() failures and more particularly, it was also possible with the exact same reproducer using overlayfs that is mounted with options index=on,nfs_export=on also on kernels < v6.6. Therefore, I am not listing the aforementioned commit as a Fixes commit. Backport hint: this patch will have a trivial conflict applying to v6.6.y, and other trivial conflicts applying to stable kernels < v6.6.

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack vector

Local

Complexity

Low

Privileges

Low

User interaction

None

Confidentiality

None

Integrity

None

Availability

High

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.3% · higher than 20% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Kernel · Linux

before 6.1.151; 6.2 before 6.6.74; 6.7 before 6.12.10; 6.13; 6.13; 6.13; +3 more · source: NVD

Linux · Linux

be77196b809cdce8603a5aadd5e3cfabd3cbef96 before 73697928c806fe4689939722184a86fc1c1957b4; be77196b809cdce8603a5aadd5e3cfabd3cbef96 before f47c834a9131ae64bee3c462f4e610c67b0a000f; be77196b809cdce8603a5aadd5e3cfabd3cbef96 before adcde2872f8fc399b249758ae1990dcd53b694ea; be77196b809cdce8603a5aadd5e3cfabd3cbef96 before 974e3fe0ac61de85015bbe5a4990cf4127b304b2; 3.8 · source: vendor

SIMATIC CN 4100 · Siemens

before V5.0 · source: CISA

SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens

V3.1.5; V3.1.6; V3.1.7; V3.1.5; V3.1.6; V3.1.7 · source: CISA

SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens

V3.1.5; V3.1.6; V3.1.7; V3.1.5; V3.1.6; V3.1.7 · source: CISA

SIPLUS S7-1500 CPU 1518-4 PN/DP MFP · Siemens

V3.1.5; V3.1.6; V3.1.7 · source: CISA

In the news

VulnerabilityHigh

Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP

View CSAF Summary Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the firmware version V3.1.6 for the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP (incl. SIPLUS variant). Siemens is preparing fix versions and recommends specific countermeasures for products where fixes are not, or not yet available. The following versions of Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP are affected: SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) vers:intdot/>=3.1.6 (CVE-2021-41617, CVE-2023-28531, CVE-2023-51384, CVE-2023-52927, CVE-2024-26783, CVE-2024-27056, CVE-2024-28956, CVE-2024-36903, CVE-2024-36927, CVE-2024-42079, CVE-2024-46786, CVE-2024-47736, CVE-2024-47809, CVE-2024-49968, CVE-2024-49994, CVE-2024-49998, CVE-2024-50014, CVE-2024-50063, CVE-2024-50164, CVE-2024-50298, CVE-2024-53124, CVE-2024-53170, CVE-2024-54458, CVE-2024-56631, CVE-2024-56703, CVE-2024-56719, CVE-2024-57917, CVE-2024-57924, CVE-2024-57973, CVE-2024-57977, CVE-2024-57979, CVE-2024-58011, CVE-2024-58016, CVE-2024-58020, CVE-2024-58056, CVE-2024-58058, CVE-2024-58061, CVE-2024-58086, CVE-2025-21645, CVE-2025-21648, CVE-2025-21655, CVE-2025-21676, CVE-2025-21682, CVE-2025-21702, CVE-2025-21705, CVE-2025-21706, CVE-2025-21707, CVE-2025-21718, CVE-2025-21731, CVE-2025-21745, CVE-2025-21758, CVE-2025-21760, CVE-2025-21764, CVE-2025-21765, CVE-2025-21780, CVE-2025-21795, CVE-2025-21796, CVE-2025-21802, CVE-2025-21814, CVE-2025-21846, CVE-2025-21853, CVE-2...

CVE-2021-41617 CVE-2023-28531 CVE-2023-51384

Jul 28, 2026·CISA Advisories

Affected product

Kernel

Linux

All Kernel CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2024-57924

CVE.org

https://www.cve.org/CVERecord?id=CVE-2024-57924

Patch