SB20260912330 - Improper Check or Handling of Exceptional Conditions in Linux kernel s390 block driver

Description

This security bulletin contains information about 1 vulnerability.

1) Improper Check or Handling of Exceptional Conditions (CVE-ID: CVE-2026-89456)

CWE-ID: CWE-703 - Improper Check or Handling of Exceptional Conditions

CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to receive zeroed data for unread portions of a request.

The vulnerability exists due to improper handling of partial-completion length in dasd_default_erp_postaction() when recovering a partially completed ESE read through the ERP chain. A local user can issue a read request that is partially completed and recovered through the ERP chain to receive zeroed data for unread portions of a request.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/15ec03452c18e8d288e519837d21b308300d74b2
• https://git.kernel.org/stable/c/6fb5ba2e7e43173a3761e46f091070a8185efa14
• https://git.kernel.org/stable/c/ceafb262475ac6cb3a7d07b1102608be2b216b99
• https://git.kernel.org/stable/c/d6b8778b1b82aa3a8dbf8612080f635b834bd16b