[Important] [Security] Virtuozzo ReadyKernel patch 122.0 for Virtuozzo Hybrid Server 7.0, Virtuozzo Infrastructure Platform 3.0, and Virtuozzo Hybrid Infrastructure 3.5, 4.0

Issue date: 2021-02-15

Applies to: Virtuozzo Hybrid Infrastructure 3.5, Virtuozzo Hybrid Infrastructure 4.0, Virtuozzo Hybrid Server 7.0, Virtuozzo Infrastructure Platform 3.0

Virtuozzo Advisory ID: VZA-2021-008

1. Overview

The cumulative Virtuozzo ReadyKernel patch was updated with security fixes. The patch applies to the kernels 3.10.0-957.12.2.vz7.96.21 (Virtuozzo Hybrid Server 7.0.11 and Virtuozzo Infrastructure Platform 3.0), 3.10.0-1062.4.2.vz7.116.7 (Virtuozzo Hybrid Server 7.0.12 HF1 and Virtuozzo Hybrid Infrastructure 3.5), 3.10.0-1062.12.1.vz7.131.10 (Virtuozzo Hybrid Server 7.0.13), 3.10.0-1127.8.2.vz7.151.14 (Virtuozzo Hybrid Server 7.0.14), 3.10.0-1127.8.2.vz7.158.8 (Virtuozzo Hybrid Infrastructure 4.0).

2. Security Fixes

  • [Important] [3.10.0-957.12.2.vz7.96.21 to 3.10.0-1127.8.2.vz7.158.8] Incorrect locking in TTY subsystem could lead to use-after-free conditions and cause memory corruption. (CVE-2020-29661)

  • [Moderate] [3.10.0-957.12.2.vz7.96.21 to 3.10.0-1127.8.2.vz7.158.8] ‘Bad unlock balance’ error in ipmr_mfc_seq_stop(). It was discovered that the implementation of IPv6 multicast routing could try to access wrong data when a user tried to read certain files in /proc. An attacker could exploit that from a container to trigger ‘bad unlock balance’ error in ipmr_mfc_seq_stop(), followed by a kernel crash. (PSBM-122990)

  • [Moderate] [3.10.0-957.12.2.vz7.96.21 to 3.10.0-1127.8.2.vz7.158.8] Soft lockup in ext4_ext_find_extent(). It was discovered that certain ioctl operations in ext4 did not check their arguments properly. An attacker could exploit that from a container to trigger soft lockups in ext4_ext_find_extent() function, which could result in a denial of service. (PSBM-122991)

3. Installing the Update

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