[Important] [Security] Virtuozzo ReadyKernel patch 122.0 for Virtuozzo Hybrid Server 7.5

The cumulative Virtuozzo ReadyKernel patch was updated with security and stability fixes. The patch applies to the kernel 3.10.0-1127.18.2.vz7.163.46 (Virtuozzo Hybrid Server 7.5).
Vulnerability id: CVE-2020-29661
Incorrect locking in TTY subsystem could lead to use-after-free conditions and cause memory corruption.

Vulnerability id: PSBM-122990
‘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.

Vulnerability id: PSBM-122991
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.