-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 ===================================================================== Red Hat Security Advisory Synopsis: Moderate: kernel-rt security and bug fix update Advisory ID: RHSA-2017:3295-01 Product: Red Hat Enterprise MRG for RHEL-6 Advisory URL: https://access.redhat.com/errata/RHSA-2017:3295 Issue date: 2017-11-30 CVE Names: CVE-2017-1000380 ===================================================================== 1. Summary: An update for kernel-rt is now available for Red Hat Enterprise MRG 2. Red Hat Product Security has rated this update as having a security impact of Moderate. 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. 2. Relevant releases/architectures: MRG Realtime for RHEL 6 Server v.2 - noarch, x86_64 3. 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): * It was found that the timer functionality in the Linux kernel ALSA subsystem is prone to a race condition between read and ioctl system call handlers, resulting in an uninitialized memory disclosure to user space. A local user could use this flaw to read information belonging to other users. (CVE-2017-1000380, Moderate) Red Hat would like to thank Alexander Potapenko (Google) for reporting this issue. Bug Fix(es): * The current realtime throttling mechanism prevents the starvation of non-realtime tasks by CPU-intensive realtime tasks. When a realtime run queue is throttled, it allows non-realtime tasks to run. If there are not non-realtime tasks, the CPU goes idle. To safely maximize CPU usage by decreasing the CPU idle time, the RT_RUNTIME_GREED scheduler feature has been implemented. When enabled, this feature checks if non-realtime tasks are starving before throttling the realtime task. The RT_RUNTIME_GREED scheduler option guarantees some run time on all CPUs for the non-realtime tasks, while keeping the realtime tasks running as much as possible. (BZ#1459275) * The kernel-rt packages have been upgraded to version 3.10.0-693.11.1.rt56.595, which provides a number of security and bug fixes over the previous version. (BZ#1500036) * In the realtime kernel, if the rt_mutex locking mechanism was taken in the interrupt context, the normal priority inheritance protocol incorrectly identified a deadlock, and a kernel panic occurred. This update reverts the patch that added rt_mutex in the interrupt context, and the kernel no longer panics due to this behavior. (BZ#1509021) 4. 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. 5. Bugs fixed (https://bugzilla.redhat.com/): 1463311 - CVE-2017-1000380 kernel: information leak due to a data race in ALSA timer 1500036 - update the MRG 2.5.z 3.10 kernel-rt sources 1509021 - [MRG-RT] Possible regression with NOHZ_FULL & rt_mutexes in IRQ (BZ1250649) 6. Package List: MRG Realtime for RHEL 6 Server v.2: Source: kernel-rt-3.10.0-693.11.1.rt56.597.el6rt.src.rpm noarch: kernel-rt-doc-3.10.0-693.11.1.rt56.597.el6rt.noarch.rpm kernel-rt-firmware-3.10.0-693.11.1.rt56.597.el6rt.noarch.rpm x86_64: kernel-rt-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-debug-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-debug-debuginfo-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-debug-devel-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-debuginfo-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-debuginfo-common-x86_64-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-devel-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-trace-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-trace-debuginfo-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-trace-devel-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-vanilla-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-vanilla-debuginfo-3.10.0-693.11.1.rt56.597.el6rt.x86_64.rpm kernel-rt-vanilla-devel-3.10.0-693.11.1.rt56.597.el6rt.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/ 7. References: https://access.redhat.com/security/cve/CVE-2017-1000380 https://access.redhat.com/security/updates/classification/#moderate 8. Contact: The Red Hat security contact is . More contact details at https://access.redhat.com/security/team/contact/ Copyright 2017 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iD8DBQFaIDvCXlSAg2UNWIIRAqNlAKCgvv0MD+8c8tUZ6PWtyo5G4VBIyQCgww6S V5ptWOp9rkSfJ6aQ/qWNjMM= =vLDd -----END PGP SIGNATURE----- -- RHSA-announce mailing list RHSA-announce@redhat.com https://www.redhat.com/mailman/listinfo/rhsa-announce