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CVE-2025-38579 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix KMSAN uninit-value in extent_info usage KMSAN reported a use of uninitialized value in `__is_extent_mergeable()` and `__is_back_mergeable()` via the read extent tree path. The root cause is that `get_read_extent_info()` only initializes three fields (`fofs`, `blk`, `len`) of `struct extent_info`, leaving the remaining fields uninitialized. This leads to undefined behavior when those fields are accessed later, especially during extent merging. Fix it by zero-initializing the `extent_info` struct before population.


Metrics

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CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://git.kernel.org/stable/c/01b6f5955e0008af6bc3a181310d2744bb349800 kernel.org Patch 
https://git.kernel.org/stable/c/08e8ab00a6d20d5544c932ee85a297d833895141 kernel.org Patch 
https://git.kernel.org/stable/c/154467f4ad033473e5c903a03e7b9bca7df9a0fa kernel.org Patch 
https://git.kernel.org/stable/c/44a79437309e0ee2276ac17aaedc71253af253a8 kernel.org Patch 
https://git.kernel.org/stable/c/cc1615d5aba4f396cf412579928539a2b124c8a0 kernel.org Patch 
https://git.kernel.org/stable/c/dabfa3952c8e6bfe6414dbf32e8b6c5f349dc898 kernel.org Patch 
https://git.kernel.org/stable/c/e68b751ec2b15d866967812c57cfdfc1eba6a269 kernel.org Patch 
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html CVE Mailing List  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-908 Use of Uninitialized Resource cwe source acceptance level NIST  

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-38579
NVD Published Date:
08/19/2025
NVD Last Modified:
01/09/2026
Source:
kernel.org