CVE-2025-40205

btrfs: avoid potential out-of-bounds in btrfs_encode_fh()

En bref

Sévérité
HIGH 7.8
EPSS
EPSS 0.15 % · centile 4 (2026-10-27)
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
Linux
Statut NVD
Deferred

Description

In the Linux kernel, the following vulnerability has been resolved: btrfs: avoid potential out-of-bounds in btrfs_encode_fh() The function btrfs_encode_fh() does not properly account for the three cases it handles. Before writing to the file handle (fh), the function only returns to the user BTRFS_FID_SIZE_NON_CONNECTABLE (5 dwords, 20 bytes) or BTRFS_FID_SIZE_CONNECTABLE (8 dwords, 32 bytes). However, when a parent exists and the root ID of the parent and the inode are different, the function writes BTRFS_FID_SIZE_CONNECTABLE_ROOT (10 dwords, 40 bytes). If *max_len is not large enough, this write goes out of bounds because BTRFS_FID_SIZE_CONNECTABLE_ROOT is greater than BTRFS_FID_SIZE_CONNECTABLE originally returned. This results in an 8-byte out-of-bounds write at fid->parent_root_objectid = parent_root_id. A previous attempt to fix this issue was made but was lost. https://lore.kernel.org/all/4CADAEEC020000780001B32C@vpn.id2.novell.com/ Although this issue does not seem to be easily triggerable, it is a potential memory corruption bug that should be fixed. This patch resolves the issue by ensuring the function returns the appropriate size for all three cases and validates that *max_len is large enough before writing any data.

Scores

VersionScoreVecteurÉvalué par
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

Références européennes

Avis du CERT-FR

Produits affectés

ProduitVersions
Linux · Linuxaffected be6e8dc0ba84029997075a1ec77b4ddb863cbe15 < 60de2f55d2aca53e81b4ef2a67d7cc9e1eb677db ; affected be6e8dc0ba84029997075a1ec77b4ddb863cbe15 < 742b44342204e5dfe3926433823623c1a0c581df ; affected be6e8dc0ba84029997075a1ec77b4ddb863cbe15 < d3a9a8e1275eb9b87f006b5562a287aea3f6885f ; affected be6e8dc0ba84029997075a1ec77b4ddb863cbe15 < d91f6626133698362bba08fbc04bd72c466806d3 ; affected be6e8dc0ba84029997075a1ec77b4ddb863cbe15 < 0276c8582488022f057b4cec21975a5edf079f47 ; affected be6e8dc0ba84029997075a1ec77b4ddb863cbe15 < 361d67276eb8ec6be8f27f4ad6c6090459438fee
Linux · Linuxaffected 2.6.29 ; unaffected 0 < 2.6.29 ; unaffected 5.4.301 ≤ 5.4.* ; unaffected 5.10.246 ≤ 5.10.* ; unaffected 5.15.195 ≤ 5.15.* ; unaffected 6.1.157 ≤ 6.1.*

Références

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD