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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.
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 race condition flaw was found in the N_HLDC Linux kernel driver when
accessing n_hdlc.tbuf list that can lead to double free. A local,
unprivileged user able to set the HDLC line discipline on the tty device
could use this flaw to increase their privileges on the system.
(CVE-2017-2636, Important)
* A use-after-free flaw was found in the way the Linux kernel's Datagram
Congestion Control Protocol (DCCP) implementation freed SKB (socket buffer)
resources for a DCCP_PKT_REQUEST packet when the IPV6_RECVPKTINFO option is
set on the socket. A local, unprivileged user could use this flaw to alter
the kernel memory, allowing them to escalate their privileges on the
system. (CVE-2017-6074, Important)
* A flaw was found in the Linux kernel key management subsystem in which a
local attacker could crash the kernel or corrupt the stack and additional
memory (denial of service) by supplying a specially crafted RSA key. This
flaw panics the machine during the verification of the RSA key.
(CVE-2016-8650, Moderate)
* A flaw was found in the Linux kernel's implementation of setsockopt for
the SO_{SND|RCV}BUFFORCE setsockopt() system call. Users with non-namespace
CAP_NET_ADMIN are able to trigger this call and create a situation in which
the sockets sendbuff data size could be negative. This could adversely
affect memory allocations and create situations where the system could
crash or cause memory corruption. (CVE-2016-9793, Moderate)
* A flaw was found in the Linux kernel's handling of clearing SELinux
attributes on /proc/pid/attr files. An empty (null) write to this file can
crash the system by causing the system to attempt to access unmapped kernel
memory. (CVE-2017-2618, Moderate)
Red Hat would like to thank Alexander Popov for reporting CVE-2017-2636;
Andrey Konovalov (Google) for reporting CVE-2017-6074; and Ralf Spenneberg
for reporting CVE-2016-8650. The CVE-2017-2618 issue was discovered by Paul
Moore (Red Hat Engineering).
Bug Fix(es):
* The kernel-rt packages have been upgraded to version 3.10.0-514.rt56.219,
which provides a number of bug fix updates over the previous version.
(BZ#1429613)
https://access.redhat.com/security/cve/CVE-2016-8650 https://access.redhat.com/security/cve/CVE-2016-9793 https://access.redhat.com/security/cve/CVE-2017-2618 https://access.redhat.com/security/cve/CVE-2017-2636 https://access.redhat.com/security/cve/CVE-2017-6074 https://access.redhat.com/security/updates/classification/#important
MRG Realtime for RHEL 6 Server v.2:
Source:
kernel-rt-3.10.0-514.rt56.219.el6rt.src.rpm
noarch:
kernel-rt-doc-3.10.0-514.rt56.219.el6rt.noarch.rpm
kernel-rt-firmware-3.10.0-514.rt56.219.el6rt.noarch.rpm
x86_64:
kernel-rt-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-debug-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-debug-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-debug-devel-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-debuginfo-common-x86_64-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-devel-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-trace-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-trace-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-trace-devel-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-vanilla-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-vanilla-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm
kernel-rt-vanilla-devel-3.10.0-514.rt56.219.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/
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 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.
MRG Realtime for RHEL 6 Server v.2 - noarch, x86_64
1395187 - CVE-2016-8650 kernel: Null pointer dereference via keyctl
1402013 - CVE-2016-9793 kernel: Signed overflow for SO_{SND|RCV}BUFFORCE
1419916 - CVE-2017-2618 kernel: Off-by-one error in selinux_setprocattr (/proc/self/attr/fscreate)
1423071 - CVE-2017-6074 kernel: use after free in dccp protocol
1428319 - CVE-2017-2636 kernel: Race condition access to n_hdlc.tbuf causes double free in n_hdlc_release()
1429613 - update the MRG 2.5.z 3.10 kernel-rt sources
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