Important kernel security update: Virtuozzo ReadyKernel patch 89.2 for Virtuozzo 7.0 and Virtuozzo Infrastructure Platform 2.5, 3.0

Issue date: 2019-10-16

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

Virtuozzo Advisory ID: VZA-2019-081

1. Overview

The cumulative Virtuozzo ReadyKernel patch was updated with security and stability fixes. The patch applies to the kernels 3.10.0-693.21.1.vz7.46.7 (Virtuozzo 7.0.7 HF2), 3.10.0-693.21.1.vz7.48.2 (Virtuozzo 7.0.7 HF3), 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).

2. Security Fixes

  • [Important] [3.10.0-693.21.1.vz7.46.7 to 3.10.0-957.12.2.vz7.96.21] Use-after-free in __blk_drain_queue() function. It was found that a use-after-free condition could be triggered in the block device subsystem while the outstanding command queue was drained. A patient local attacker can use this flaw to crash the system or, potentially, to escalate their privileges. (CVE-2018-20856)

  • [Moderate] [3.10.0-693.21.1.vz7.46.7 to 3.10.0-957.12.2.vz7.96.21] tun: potential kernel crash when TUNSETIFF ioctl operation is used for a device with an invalid name. (CVE-2018-7191)

  • [Moderate] [3.10.0-693.21.1.vz7.46.7 to 3.10.0-957.12.2.vz7.96.21] Certain operations with iptables in a container may crash the kernel. (PSBM-98522)

  • [Moderate] [3.10.0-693.21.1.vz7.46.7 to 3.10.0-957.12.2.vz7.96.21] A container that tries to mount NFS shares may cause the whole system to hang in certain conditions. (PSBM-98297)

3. Bug Fixes

  • [3.10.0-862.20.2.vz7.73.24 to 3.10.0-957.12.2.vz7.96.21] sunrpc: kernel crash in svcauth_unix_set_client(). (PSBM-97738)

  • [3.10.0-957.12.2.vz7.96.21] Base ploop images containing holes could become larger than needed after merge. (PSBM-98313)

4. Installing the Update

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