[RHSA-2021:2316] 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: Integer overflow in Intel(R) Graphics Drivers (CVE-2020-12362)

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

• kernel: use-after-free in n_tty_receive_buf_common function in drivers/tty/n_tty.c (CVE-2020-8648)

• kernel: Improper input validation in some Intel(R) Graphics Drivers (CVE-2020-12363)

• kernel: Null pointer dereference in some Intel(R) Graphics Drivers (CVE-2020-12364)

• kernel: Speculation on pointer arithmetic against bpf_context pointer (CVE-2020-27170)

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):

• lru-add-drain workqueue on RT is allocated without being used (BZ#1894587)

• kernel-rt: update to the latest RHEL7.9.z source tree (BZ#1953118)