RedHat: RHSA-2021-4648:04 Important: kernel-rt security and bug fix update
Summary
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: Insufficient validation of user-supplied sizes for the MSG_CRYPTO
message type (CVE-2021-43267)
* kernel: timer tree corruption leads to missing wakeup and system freeze
(CVE-2021-20317)
* kernel: fuse: stall on CPU can occur because a retry loop continually
finds the same bad inode (CVE-2021-28950)
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: update RT source tree to the RHEL-8.4.z5 source tree
(BZ#2017122)
Summary
Solution
For details on how to apply this update, which includes the changes
described in this advisory, refer to:
https://access.redhat.com/articles/11258
The system must be rebooted for this update to take effect.
References
https://access.redhat.com/security/cve/CVE-2021-20317 https://access.redhat.com/security/cve/CVE-2021-28950 https://access.redhat.com/security/cve/CVE-2021-43267 https://access.redhat.com/security/updates/classification/#important
Package List
Red Hat Enterprise Linux Real Time for NFV EUS (v.8.4):
Source:
kernel-rt-4.18.0-305.28.1.rt7.100.el8_4.src.rpm
x86_64:
kernel-rt-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-core-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-core-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-debuginfo-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-devel-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-kvm-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-modules-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-modules-extra-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debuginfo-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debuginfo-common-x86_64-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-devel-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-kvm-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-modules-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-modules-extra-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
Red Hat Enterprise Linux Real Time EUS (v.8.4):
Source:
kernel-rt-4.18.0-305.28.1.rt7.100.el8_4.src.rpm
x86_64:
kernel-rt-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-core-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-core-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-debuginfo-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-devel-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-modules-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debug-modules-extra-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debuginfo-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-debuginfo-common-x86_64-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-devel-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-modules-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
kernel-rt-modules-extra-4.18.0-305.28.1.rt7.100.el8_4.x86_64.rpm
These packages are GPG signed by Red Hat for security. Our key and
details on how to verify the signature are available from
https://access.redhat.com/security/team/key/
Topic
An update for kernel-rt is now available for Red Hat Enterprise Linux 8.4Extended Update Support.Red Hat Product Security has rated this update as having a security impactof Important. A Common Vulnerability Scoring System (CVSS) base score,which gives a detailed severity rating, is available for each vulnerabilityfrom the CVE link(s) in the References section.
Topic
Relevant Releases Architectures
Red Hat Enterprise Linux Real Time EUS (v.8.4) - x86_64
Red Hat Enterprise Linux Real Time for NFV EUS (v.8.4) - x86_64
Bugs Fixed
1941762 - CVE-2021-28950 kernel: fuse: stall on CPU can occur because a retry loop continually finds the same bad inode
2005258 - CVE-2021-20317 kernel: timer tree corruption leads to missing wakeup and system freeze
2020362 - CVE-2021-43267 kernel: Insufficient validation of user-supplied sizes for the MSG_CRYPTO message type