(RHSA-2021:5227) Moderate: kernel security and bug fix update

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: In Overlayfs missing a check for a negative dentry before calling vfs_rename() (CVE-2021-20321)

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):

• panic while breaking a lease/delegation after user mode helper invocation (BZ#2010333)

• The ASR driver is causing a system crash in RHEL8.4 compared to RHEL8.3 due to kernel changes (BZ#2016384)

• RHEL8: DFS provided SMB shares are not accessible following unprivileged access (BZ#2017177)

• Avoid hitting the rtnl_trylock/restart_syscall logic in net-sysfs when possible (BZ#2021165)

• RHEL8: x86/Kconfig: Do not enable AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT (BZ#2024678)

• RHEL8.4-[Regression][P10][DD2.0][Rainier/Denali] - system crashed while offlining and onlining cores (BZ#2026450)