RHSA-2021:1070: Red Hat Security Advisory: kernel-rt security and bug fix update

An update for kernel-rt is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.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: out-of-bounds read in libiscsi module (CVE-2021-27364)
• kernel: heap buffer overflow in the iSCSI subsystem (CVE-2021-27365)
• 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):
• RHEL7.9 Realtime crashes due to a blocked task detection. The blocked task is stuck in unregister_shrinker() where multiple tasks have taken the shrinker_rwsem and are fighting on a dentry’s d_lockref lock rt_mutex. [kernel-rt] (BZ#1935557)
• kernel-rt: update to the latest RHEL7.9.z5 source tree (BZ#1939220) Related CVEs:
• CVE-2021-27363: kernel: iscsi: unrestricted access to sessions and handles
• CVE-2021-27364: kernel: out-of-bounds read in libiscsi module
• CVE-2021-27365: kernel: heap buffer overflow in the iSCSI subsystem