Important kernel security update: Virtuozzo ReadyKernel patch 97.0 for Virtuozzo 7.0, Virtuozzo Infrastructure Platform 2.5, 3.0 and Virtuozzo Hybrid Infrastructure 3.5

Issue date: 2020-02-10

Applies to: Virtuozzo 7.0, Virtuozzo Infrastructure Platform 2.5, Virtuozzo Infrastructure Platform 3.0, Virtuozzo Hybrid Infrastructure 3.5

Virtuozzo Advisory ID: VZA-2020-013

1. Overview

The cumulative Virtuozzo ReadyKernel patch was updated with security and stability fixes. The patch applies to the kernels 3.10.0-862.9.1.vz7.63.3 (Virtuozzo 7.0.8), 3.10.0-862.11.6.vz7.64.7 (Virtuozzo 7.0.8 HF1), 3.10.0-862.20.2.vz7.73.24 (Virtuozzo 7.0.9 and Virtuozzo Infrastructure Platform 2.5), 3.10.0-862.20.2.vz7.73.29 (Virtuozzo 7.0.9 and Virtuozzo Infrastructure Platform 2.5), 3.10.0-957.10.1.vz7.85.17 (Virtuozzo 7.0.10), 3.10.0-957.12.2.vz7.86.2 (Virtuozzo 7.0.10 HF1), 3.10.0-957.12.2.vz7.96.21 (Virtuozzo 7.0.11 and Virtuozzo Infrastructure Platform 3.0), 3.10.0-1062.4.2.vz7.116.7 (Virtuozzo 7.0.12 HF1 and Virtuozzo Hybrid Infrastructure 3.5).

2. Security Fixes

  • [Important] [3.10.0-862.9.1.vz7.63.3 to 3.10.0-862.20.2.vz7.73.29] Use-after-free in fs/xfs/xfs_super.c. A flaw was found in the implementation of XFS filesystem where a key data structure (sb->s_fs_info) may not be de-allocated properly when the system is under memory pressure. This could allow a local attacker to create a use-after-free situation which can result in memory corruption or, potentially, privilege escalation. (CVE-2018-20976)

  • [Moderate] [3.10.0-862.9.1.vz7.63.3 to 3.10.0-1062.4.2.vz7.116.7] Kernel crash due to out-of-bounds memory accesses in process_vm_readv(). It was discovered that the implementation of process_vm_readv() system call could try to access memory outside of the structures it was processing in certain cases. A local unprivileged user could use this vulnerability to crash the system. (PSBM-94695)

3. Bug Fixes

  • [3.10.0-957.12.2.vz7.96.21 to 3.10.0-1062.4.2.vz7.116.7] Certain operations with an empty ploop image could lead to its unexpected growth. (PSBM-101143)

  • [3.10.0-1062.4.2.vz7.116.7] quotaoff operation executed in a container could get stuck in D state. (PSBM-101159)

  • [3.10.0-1062.4.2.vz7.116.7] Incomplete fix for PSBM-100575: reading of /proc/bc/resources line by line would never end. (PSBM-101249)

4. Installing the Update

Download, install, and immediately apply the patch to the current kernel by running ‘readykernel update’.