Synopsis

Important: kernel-rt security update

Type/Severity

Security Advisory: Important

Topic

An update for kernel-rt is now available for Red Hat Enterprise Linux 8.

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.

Description

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

Security Fix(es):

• A flaw was found in the implementation of the "fill buffer", a mechanism used by modern CPUs when a cache-miss is made on L1 CPU cache. If an attacker can generate a load operation that would create a page fault, the execution will continue speculatively with incorrect data from the fill buffer while the data is fetched from higher level caches. This response time can be measured to infer data in the fill buffer. (CVE-2018-12130)
  
• Modern Intel microprocessors implement hardware-level micro-optimizations to improve the performance of writing data back to CPU caches. The write operation is split into STA (STore Address) and STD (STore Data) sub-operations. These sub-operations allow the processor to hand-off address generation logic into these sub-operations for optimized writes. Both of these sub-operations write to a shared distributed processor structure called the 'processor store buffer'. As a result, an unprivileged attacker could use this flaw to read private data resident within the CPU's processor store buffer. (CVE-2018-12126)
  
• Microprocessors use a ‘load port’ subcomponent to perform load operations from memory or IO. During a load operation, the load port receives data from the memory or IO subsystem and then provides the data to the CPU registers and operations in the CPU’s pipelines. Stale load operations results are stored in the 'load port' table until overwritten by newer operations. Certain load-port operations triggered by an attacker can be used to reveal data about previous stale requests leaking data back to the attacker via a timing side-channel. (CVE-2018-12127)
  
• Uncacheable memory on some microprocessors utilizing speculative execution may allow an authenticated user to potentially enable information disclosure via a side channel with local access. (CVE-2019-11091)
  

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.

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.

Affected Products

• Red Hat Enterprise Linux for Real Time 8 x86_64
• Red Hat Enterprise Linux for Real Time for NFV 8 x86_64

Fixes

• BZ - 1646781 - CVE-2018-12126 hardware: Microarchitectural Store Buffer Data Sampling (MSBDS)
• BZ - 1646784 - CVE-2018-12130 hardware: Microarchitectural Fill Buffer Data Sampling (MFBDS)
• BZ - 1667782 - CVE-2018-12127 hardware: Micro-architectural Load Port Data Sampling - Information Leak (MLPDS)
• BZ - 1705312 - CVE-2019-11091 hardware: Microarchitectural Data Sampling Uncacheable Memory (MDSUM)

CVEs

• CVE-2018-12126
• CVE-2018-12127
• CVE-2018-12130
• CVE-2019-11091

References

• https://access.redhat.com/security/updates/classification/#important
• https://access.redhat.com/security/vulnerabilities/mds

Red Hat Enterprise Linux for Real Time 8

SRPM
kernel-rt-4.18.0-80.1.2.rt9.145.el8_0.src.rpm	SHA-256: 32c6baff67250ed1ed0825df74627f175dcfdaddfed13f04898e7f93a0767e30
x86_64
kernel-rt-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: acf4af642bc43d1da058aad4683390ca69d7c20443173c6b0cc340fce0d0d124
kernel-rt-core-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: e4e2354c9cd8ece16ea6026059e31710d0fc44becdf29461885ae62c1ada007b
kernel-rt-debug-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: caa9cfd883b89316941c25e1cb9096d8c90d409679bb1641563cb825ddc2e16a
kernel-rt-debug-core-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 3650fa75a9af8477d8c7fa066c0cf134f6d8778c33f213f64fa41f6c066b04f2
kernel-rt-debug-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: f7f66d18263034cba8f06de161989a455419f52fab52d6e8bf7772e17a84c13e
kernel-rt-debug-devel-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 239e22d43c9b95ec3ed59c98619d86b9208b0a6ee3004a8819f93356955af920
kernel-rt-debug-kvm-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 1d028115e774122abcead17b8e35337633c4b76f03fa69434c2b5adb78231a98
kernel-rt-debug-modules-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 0663590a249ffc35441bea81804509a7683a0a1d9f9d3e2a5d12a04b0dae067d
kernel-rt-debug-modules-extra-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 9a32d51d68fd27ee60b1e23478dc82027a2a4e441e22f9a0ca942cfc46a65502
kernel-rt-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 0d7ae8382881ccb8c439e78dae5ed363d9dfad50338429fd669a1e85dca3c952
kernel-rt-debuginfo-common-x86_64-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: b73656649891b222225e59317a68ce22734ca45ce13eb2ac36ebde376da32b70
kernel-rt-devel-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: b2c1602107f89204389b9a26760dcbacaaa44dcb0bed996718b9d663d70962c9
kernel-rt-kvm-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 2969525dc3b52e4aa027604a3c19090c0fc3e3de5ca9379a69ee09f1858cd72a
kernel-rt-modules-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 7546721e4d65225e9f513c204f00262478cbedfbb31e1f47b511d9f11baaa228
kernel-rt-modules-extra-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 4a6c5433edc6e1f18b0a6f8c8106242f79de70e8fff3d4b1a3cbf44721ac96bc

Red Hat Enterprise Linux for Real Time for NFV 8

SRPM
kernel-rt-4.18.0-80.1.2.rt9.145.el8_0.src.rpm	SHA-256: 32c6baff67250ed1ed0825df74627f175dcfdaddfed13f04898e7f93a0767e30
x86_64
kernel-rt-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: acf4af642bc43d1da058aad4683390ca69d7c20443173c6b0cc340fce0d0d124
kernel-rt-core-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: e4e2354c9cd8ece16ea6026059e31710d0fc44becdf29461885ae62c1ada007b
kernel-rt-debug-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: caa9cfd883b89316941c25e1cb9096d8c90d409679bb1641563cb825ddc2e16a
kernel-rt-debug-core-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 3650fa75a9af8477d8c7fa066c0cf134f6d8778c33f213f64fa41f6c066b04f2
kernel-rt-debug-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: f7f66d18263034cba8f06de161989a455419f52fab52d6e8bf7772e17a84c13e
kernel-rt-debug-devel-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 239e22d43c9b95ec3ed59c98619d86b9208b0a6ee3004a8819f93356955af920
kernel-rt-debug-kvm-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 63e4d63575f1665d2d229c08bc9ac10c84debe6574c8ad503afb73f7cd72be40
kernel-rt-debug-kvm-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 1d028115e774122abcead17b8e35337633c4b76f03fa69434c2b5adb78231a98
kernel-rt-debug-modules-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 0663590a249ffc35441bea81804509a7683a0a1d9f9d3e2a5d12a04b0dae067d
kernel-rt-debug-modules-extra-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 9a32d51d68fd27ee60b1e23478dc82027a2a4e441e22f9a0ca942cfc46a65502
kernel-rt-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 0d7ae8382881ccb8c439e78dae5ed363d9dfad50338429fd669a1e85dca3c952
kernel-rt-debuginfo-common-x86_64-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: b73656649891b222225e59317a68ce22734ca45ce13eb2ac36ebde376da32b70
kernel-rt-devel-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: b2c1602107f89204389b9a26760dcbacaaa44dcb0bed996718b9d663d70962c9
kernel-rt-kvm-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 7f7087c7ce2bcb9306ba7435276e219cf87c8eb8d9dd830013f60f9f8bb2cd50
kernel-rt-kvm-debuginfo-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 2969525dc3b52e4aa027604a3c19090c0fc3e3de5ca9379a69ee09f1858cd72a
kernel-rt-modules-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 7546721e4d65225e9f513c204f00262478cbedfbb31e1f47b511d9f11baaa228
kernel-rt-modules-extra-4.18.0-80.1.2.rt9.145.el8_0.x86_64.rpm	SHA-256: 4a6c5433edc6e1f18b0a6f8c8106242f79de70e8fff3d4b1a3cbf44721ac96bc