(RHSA-2017:2077) Important: kernel-rt security, bug fix, and enhancement update

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

Security Fix(es):

• An use-after-free flaw was found in the Linux kernel which enables a race condition in the L2TPv3 IP Encapsulation feature. A local user could use this flaw to escalate their privileges or crash the system. (CVE-2016-10200, Important)

• A flaw was found that can be triggered in keyring_search_iterator in keyring.c if type->match is NULL. A local user could use this flaw to crash the system or, potentially, escalate their privileges. (CVE-2017-2647, Important)

• It was found that the NFSv4 server in the Linux kernel did not properly validate layout type when processing NFSv4 pNFS LAYOUTGET and GETDEVICEINFO operands. A remote attacker could use this flaw to soft-lockup the system and thus cause denial of service. (CVE-2017-8797, Important)

This update also fixes multiple Moderate and Low impact security issues:

• CVE-2015-8839, CVE-2015-8970, CVE-2016-9576, CVE-2016-7042, CVE-2016-7097, CVE-2016-8645, CVE-2016-9576, CVE-2016-9588, CVE-2016-9806, CVE-2016-10088, CVE-2016-10147, CVE-2017-2596, CVE-2017-2671, CVE-2017-5970, CVE-2017-6001, CVE-2017-6951, CVE-2017-7187, CVE-2017-7616, CVE-2017-7889, CVE-2017-8890, CVE-2017-9074, CVE-2017-8890, CVE-2017-9075, CVE-2017-8890, CVE-2017-9076, CVE-2017-8890, CVE-2017-9077, CVE-2017-9242, CVE-2014-7970, CVE-2014-7975, CVE-2016-6213, CVE-2016-9604, CVE-2016-9685

Documentation for these issues is available from the Release Notes document linked from the References section.

Red Hat would like to thank Igor Redko (Virtuozzo) and Andrey Ryabinin (Virtuozzo) for reporting CVE-2017-2647; Igor Redko (Virtuozzo) and Vasily Averin (Virtuozzo) for reporting CVE-2015-8970; Marco Grassi for reporting CVE-2016-8645; and Dmitry Vyukov (Google Inc.) for reporting CVE-2017-2596. The CVE-2016-7042 issue was discovered by Ondrej Kozina (Red Hat); the CVE-2016-7097 issue was discovered by Andreas Gruenbacher (Red Hat) and Jan Kara (SUSE); the CVE-2016-6213 and CVE-2016-9685 issues were discovered by Qian Cai (Red Hat); and the CVE-2016-9604 issue was discovered by David Howells (Red Hat).

Additional Changes:

For detailed information on other changes in this release, see the Red Hat Enterprise Linux 7.4 Release Notes linked from the References section.