CVE-2026-46078 PUBLISHED

erofs: fix the out-of-bounds nameoff handling for trailing dirents

Assigner: Linux
Reserved: 13.05.2026 Published: 27.05.2026 Updated: 27.05.2026

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

erofs: fix the out-of-bounds nameoff handling for trailing dirents

Currently we already have boundary-checks for nameoffs, but the trailing dirents are special since the namelens are calculated with strnlen() with unchecked nameoffs.

If a crafted EROFS has a trailing dirent with nameoff >= maxsize, maxsize - nameoff can underflow, causing strnlen() to read past the directory block.

nameoff0 should also be verified to be a multiple of sizeof(struct erofs_dirent) as well [1].

[1] https://sashiko.dev/#/patchset/20260416063511.3173774-1-hsiangkao%40linux.alibaba.com

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from 3aa8ec716e52c02360457fa018296629b4d0becf to 222055e6b4063abd2d9e13c3d49bbd1724c50789 (excl.)
  • affected from 3aa8ec716e52c02360457fa018296629b4d0becf to 48b27a955d22391c7f30169fa7b6b2e1977f1ce4 (excl.)
  • affected from 3aa8ec716e52c02360457fa018296629b4d0becf to 8ebb951a284b7446e025afc7dc5e9516ef9a7214 (excl.)
  • affected from 3aa8ec716e52c02360457fa018296629b4d0becf to 1d55445226c75ddd4e78b09b3e7d99109b28c366 (excl.)
  • affected from 3aa8ec716e52c02360457fa018296629b4d0becf to d18a3b5d337fa412a38e776e6b4b857a58836575 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 4.19 is affected
  • unaffected from 0 to 4.19 (excl.)
  • unaffected from 6.6.140 to 6.6.* (incl.)
  • unaffected from 6.12.86 to 6.12.* (incl.)
  • unaffected from 6.18.27 to 6.18.* (incl.)
  • unaffected from 7.0.4 to 7.0.* (incl.)
  • unaffected from 7.1-rc1 to * (incl.)

References