(RHSA-2021:1081) Important: kernel-rt security and bug fix update

The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.

Security Fix(es):

• kernel: use after free in eventpoll.c may lead to escalation of privilege (CVE-2020-0466)

• kernel: SCSI target (LIO) write to any block on ILO backstore (CVE-2020-28374)

• kernel: Use after free via PI futex state (CVE-2021-3347)

• kernel: race conditions caused by wrong locking in net/vmw_vsock/af_vsock.c (CVE-2021-26708)

• kernel: out-of-bounds read in libiscsi module (CVE-2021-27364)

• kernel: heap buffer overflow in the iSCSI subsystem (CVE-2021-27365)

• Kernel: KVM: host stack overflow due to lazy update IOAPIC (CVE-2020-27152)

• kernel: iscsi: unrestricted access to sessions and handles (CVE-2021-27363)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• kernel-rt possible livelock: WARNING: CPU: 28 PID: 3109 at kernel/ptrace.c:242 ptrace_check_attach+0xdd/0x1a0 (BZ#1925308)

• kernel-rt: update RT source tree to the RHEL-8.3.z3 source tree (BZ#1926369)