ESB-2017.1890 - [RedHat] kernel-rt: Multiple vulnerabilities 2017-08-02

Printable version
PGP/GPG verifiable version

Hash: SHA256

             AUSCERT External Security Bulletin Redistribution

      Important: kernel-rt security, bug fix, and enhancement update
                               2 August 2017


        AusCERT Security Bulletin Summary

Product:           kernel-rt
Publisher:         Red Hat
Operating System:  Red Hat
Impact/Access:     Root Compromise        -- Existing Account      
                   Access Privileged Data -- Existing Account      
                   Denial of Service      -- Existing Account      
                   Reduced Security       -- Remote/Unauthenticated
Resolution:        Patch/Upgrade
CVE Names:         CVE-2017-9242 CVE-2017-9077 CVE-2017-9076
                   CVE-2017-9075 CVE-2017-9074 CVE-2017-8890
                   CVE-2017-8797 CVE-2017-7889 CVE-2017-7616
                   CVE-2017-7187 CVE-2017-6951 CVE-2017-6001
                   CVE-2017-5970 CVE-2017-2671 CVE-2017-2647
                   CVE-2017-2596 CVE-2016-10200 CVE-2016-10147
                   CVE-2016-10088 CVE-2016-9806 CVE-2016-9685
                   CVE-2016-9604 CVE-2016-9588 CVE-2016-9576
                   CVE-2016-8645 CVE-2016-7097 CVE-2016-7042
                   CVE-2016-6213 CVE-2015-8970 CVE-2015-8839
                   CVE-2014-7975 CVE-2014-7970 

Reference:         ASB-2017.0032

Original Bulletin:

- --------------------------BEGIN INCLUDED TEXT--------------------

Hash: SHA1

                   Red Hat Security Advisory

Synopsis:          Important: kernel-rt security, bug fix, and enhancement update
Advisory ID:       RHSA-2017:2077-01
Product:           Red Hat Enterprise Linux
Advisory URL:
Issue date:        2017-08-01
CVE Names:         CVE-2014-7970 CVE-2014-7975 CVE-2015-8839 
                   CVE-2015-8970 CVE-2016-10088 CVE-2016-10147 
                   CVE-2016-10200 CVE-2016-6213 CVE-2016-7042 
                   CVE-2016-7097 CVE-2016-8645 CVE-2016-9576 
                   CVE-2016-9588 CVE-2016-9604 CVE-2016-9685 
                   CVE-2016-9806 CVE-2017-2596 CVE-2017-2647 
                   CVE-2017-2671 CVE-2017-5970 CVE-2017-6001 
                   CVE-2017-6951 CVE-2017-7187 CVE-2017-7616 
                   CVE-2017-7889 CVE-2017-8797 CVE-2017-8890 
                   CVE-2017-9074 CVE-2017-9075 CVE-2017-9076 
                   CVE-2017-9077 CVE-2017-9242 

1. Summary:

An update for kernel-rt is now available for Red Hat Enterprise Linux 7.

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.

2. Relevant releases/architectures:

Red Hat Enterprise Linux for Real Time (v. 7) - noarch, x86_64
Red Hat Enterprise Linux for Real Time for NFV (v. 7) - 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):

* 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,

* 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.

4. Solution:

For details on how to apply this update, which includes the changes
described in this advisory, refer to:

The system must be rebooted for this update to take effect.

5. Bugs fixed (

1151095 - CVE-2014-7970 Kernel: fs: VFS denial of service
1151108 - CVE-2014-7975 Kernel: fs: umount denial of service
1323577 - CVE-2015-8839 kernel: ext4 filesystem page fault race condition with fallocate call.
1356471 - CVE-2016-6213 kernel: Overflowing kernel mount table using shared bind mount
1368938 - CVE-2016-7097 kernel: Setting a POSIX ACL via setxattr doesn't clear the setgid bit
1373966 - CVE-2016-7042 kernel: Stack corruption while reading /proc/keys when gcc stack protector is enabled
1377840 - kernel-rt: update to the RHEL7.3.z batch#1 source tree
1378172 - KVM-RT: halting and starting guests cause latency spikes
1386286 - CVE-2015-8970 kernel: crypto: GPF in lrw_crypt caused by null-deref
1389215 - RT kernel panics with dm-multipath enabled
1389433 - CVE-2016-9604 kernel: security: The built-in keyrings for security tokens can be joined as a session and then modified by the root user
1393904 - CVE-2016-8645 kernel: a BUG() statement can be hit in net/ipv4/tcp_input.c
1396941 - CVE-2016-9685 kernel: Memory leaks in xfs_attr_list.c error paths
1400188 - kernel-rt: update to the RHEL7.3.z batch#2 source tree
1401502 - CVE-2016-9806 kernel: netlink: double-free in netlink_dump
1403145 - CVE-2016-9576 kernel: Use after free in SCSI generic device interface
1404200 - CVE-2016-10147 kernel: Kernel crash by spawning mcrypt(alg) with incompatible algorithm
1404924 - CVE-2016-9588 Kernel: kvm: nVMX: uncaught software exceptions in L1 guest leads to DoS
1412210 - CVE-2016-10088 kernel: Use after free in SCSI generic device interface (CVE-2016-9576 regression)
1414052 - kernel-rt: update to the RHEL7.3.z batch#3 source tree
1417812 - CVE-2017-2596 Kernel: kvm: page reference leakage in handle_vmon
1421638 - CVE-2017-5970 kernel: ipv4: Invalid IP options could cause skb->dst drop
1421801 - [rt] update driver modifications from upstream PREEMPT_RT patchset
1421810 - [rt] implement the simple work queue from upstream PREEMPT_RT series
1422825 - CVE-2017-6001 kernel: Race condition between multiple sys_perf_event_open() calls
1425780 - latencyhist: disable jump-labels
1426661 - BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:915
1427626 - [rt] x86_64 specific updates from upstream PREEMPT_RT patchset
1427647 - [rt] dump stack: don't disable preemption during trace
1427991 - lockdep: selftest: fix warnings due to missing PREEMPT_RT conditionals
1428353 - CVE-2017-2647 kernel: Null pointer dereference in search_keyring
1428890 - update softirq: Check preemption after reenabling interrupts
1428943 - Consider backport "ftrace: Fix trace header alignment"
1429610 - kernel-rt: update to the RHEL7.3.z batch#4 source tree
1429640 - [rt] ipc/msg: Implement lockless pipelined wakeups
1429951 - [rt] fs: dcache: Use cpu_chill() in trylock loops
1429977 - workqueue: use rcu_readlock() in put_pwq_unlocked()
1430023 - snd/pcm: fix snd_pcm_stream_lock*() irqs_disabled() splats
1430038 - Add missing hunk for upstream skbufhead-raw-lock RT patches
1430074 - Backport "net: dev: always take qdisc's busylock in __dev_xmit_skb" upstream RT patch
1430347 - CVE-2016-10200 kernel: l2tp: Race condition in the L2TPv3 IP encapsulation feature
1430353 - net: add back the missing serialization in  ip_send_unicast_reply()
1430926 - percpu_ida: Use local locks
1430946 - sas-ata/isci: dont't disable interrupts in qc_issue handler
1431104 - cpu hotplug: Document why PREEMPT_RT uses a spinlock
1432118 - hotplug: Use set_cpus_allowed_ptr() in sync_unplug_thread()
1433252 - CVE-2017-6951 kernel: NULL pointer dereference in keyring_search_aux function
1434327 - CVE-2017-7187 kernel: scsi: Stack-based buffer overflow in sg_ioctl function
1434616 - CPU hotplug causes lglock to be taken from atomic context
1436649 - CVE-2017-2671 kernel: ping socket / AF_LLC connect() sin_family race
1438512 - [rt] pull patchset that lifts single reader restriction on rwsems
1441088 - CVE-2017-7616 kernel: Incorrect error handling in the set_mempolicy and mbind compat syscalls in mm/mempolicy.c
1441552 - kernel BUG at kernel/sched/rt.c:2021!
1444493 - CVE-2017-7889 kernel: mm subsystem does not properly enforce the CONFIG_STRICT_DEVMEM protection mechanism
1450972 - CVE-2017-8890 kernel: Double free in the inet_csk_clone_lock function in net/ipv4/inet_connection_sock.c
1452240 - kvmgt.ko needs unknown symbol
1452679 - CVE-2017-9074 kernel: net: IPv6 fragmentation implementation of nexthdr field may be associated with an invalid option
1452688 - CVE-2017-9076 kernel: net: IPv6 DCCP implementation mishandles inheritance
1452691 - CVE-2017-9075 kernel: net: sctp_v6_create_accept_sk function mishandles inheritance
1452744 - CVE-2017-9077 kernel: net: tcp_v6_syn_recv_sock function mishandles inheritance
1456388 - CVE-2017-9242 kernel: Incorrect overwrite check in __ip6_append_data()
1459056 - Boot/Shutdown RT guest with kernel-rt-debug will cause "BUG: sleeping function called from invalid context at kernel/rtmutex.c:818"
1466329 - CVE-2017-8797 kernel: NFSv4 server does not properly validate layout type when processing NFSv4 pNFS LAYOUTGET operand

6. Package List:

Red Hat Enterprise Linux for Real Time for NFV (v. 7):




Red Hat Enterprise Linux for Real Time (v. 7):




These packages are GPG signed by Red Hat for security.  Our key and
details on how to verify the signature are available from

7. References:

8. Contact:

The Red Hat security contact is <>. More contact
details at

Copyright 2017 Red Hat, Inc.
Version: GnuPG v1


- --
RHSA-announce mailing list

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to
and we will forward your request to the appropriate person.

NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

Australian Computer Emergency Response Team
The University of Queensland
Qld 4072

Internet Email:
Facsimile:      (07) 3365 7031
Telephone:      (07) 3365 4417 (International: +61 7 3365 4417)
                AusCERT personnel answer during Queensland business hours
                which are GMT+10:00 (AEST).
                On call after hours for member emergencies only.


« Back to bulletins