[SECURITY] [DSA 4188-1] linux security update

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Debian Security Advisory DSA-4188-1 [email protected]
https://www.debian.org/security/ Salvatore Bonaccorso
May 01, 2018 https://www.debian.org/security/faq

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Package : linux
CVE ID : CVE-2017-5715 CVE-2017-5753 CVE-2017-17975 CVE-2017-18193
CVE-2017-18216 CVE-2017-18218 CVE-2017-18222 CVE-2017-18224
CVE-2017-18241 CVE-2017-18257 CVE-2018-1065 CVE-2018-1066
CVE-2018-1068 CVE-2018-1092 CVE-2018-1093 CVE-2018-1108
CVE-2018-5803 CVE-2018-7480 CVE-2018-7566 CVE-2018-7740
CVE-2018-7757 CVE-2018-7995 CVE-2018-8087 CVE-2018-8781
CVE-2018-8822 CVE-2018-10323 CVE-2018-1000199

Several vulnerabilities have been discovered in the Linux kernel that
may lead to a privilege escalation, denial of service or information
leaks.

CVE-2017-5715

Multiple researchers have discovered a vulnerability in various
processors supporting speculative execution, enabling an attacker
controlling an unprivileged process to read memory from arbitrary
addresses, including from the kernel and all other processes
running on the system.

This specific attack has been named Spectre variant 2 (branch
target injection) and is mitigated for the x86 architecture (amd64
and i386) by using the "retpoline" compiler feature which allows
indirect branches to be isolated from speculative execution.

CVE-2017-5753

Multiple researchers have discovered a vulnerability in various
processors supporting speculative execution, enabling an attacker
controlling an unprivileged process to read memory from arbitrary
addresses, including from the kernel and all other processes
running on the system.

This specific attack has been named Spectre variant 1
(bounds-check bypass) and is mitigated by identifying vulnerable
code sections (array bounds checking followed by array access) and
replacing the array access with the speculation-safe
array_index_nospec() function.

More use sites will be added over time.

CVE-2017-17975

Tuba Yavuz reported a use-after-free flaw in the USBTV007
audio-video grabber driver. A local user could use this for denial
of service by triggering failure of audio registration.

CVE-2017-18193

Yunlei He reported that the f2fs implementation does not properly
handle extent trees, allowing a local user to cause a denial of
service via an application with multiple threads.

CVE-2017-18216

Alex Chen reported that the OCFS2 filesystem failed to hold a
necessary lock during nodemanager sysfs file operations,
potentially leading to a null pointer dereference.  A local user
could use this for denial of service.

CVE-2017-18218

Jun He reported a user-after-free flaw in the Hisilicon HNS ethernet
driver. A local user could use this for denial of service.

CVE-2017-18222

It was reported that the Hisilicon Network Subsystem (HNS) driver
implementation does not properly handle ethtool private flags. A
local user could use this for denial of service or possibly have
other impact.

CVE-2017-18224

Alex Chen reported that the OCFS2 filesystem omits the use of a
semaphore and consequently has a race condition for access to the
extent tree during read operations in DIRECT mode. A local user
could use this for denial of service.

CVE-2017-18241

Yunlei He reported that the f2fs implementation does not properly
initialise its state if the "noflush_merge" mount option is used.
A local user with access to a filesystem mounted with this option
could use this to cause a denial of service.

CVE-2017-18257

It was reported that the f2fs implementation is prone to an infinite
loop caused by an integer overflow in the __get_data_block()
function. A local user can use this for denial of service via
crafted use of the open and fallocate system calls with an
FS_IOC_FIEMAP ioctl.

CVE-2018-1065

The syzkaller tool found a NULL pointer dereference flaw in the
netfilter subsystem when handling certain malformed iptables
rulesets. A local user with the CAP_NET_RAW or CAP_NET_ADMIN
capability (in any user namespace) could use this to cause a denial
of service. Debian disables unprivileged user namespaces by default.

CVE-2018-1066

Dan Aloni reported to Red Hat that the CIFS client implementation
would dereference a null pointer if the server sent an invalid
response during NTLMSSP setup negotiation.  This could be used
by a malicious server for denial of service.

CVE-2018-1068

The syzkaller tool found that the 32-bit compatibility layer of
ebtables did not sufficiently validate offset values. On a 64-bit
kernel, a local user with the CAP_NET_ADMIN capability (in any user
namespace) could use this to overwrite kernel memory, possibly
leading to privilege escalation. Debian disables unprivileged user
namespaces by default.

CVE-2018-1092

Wen Xu reported that a crafted ext4 filesystem image would
trigger a null dereference when mounted.  A local user able
to mount arbitrary filesystems could use this for denial of
service.

CVE-2018-1093

Wen Xu reported that a crafted ext4 filesystem image could trigger
an out-of-bounds read in the ext4_valid_block_bitmap() function. A
local user able to mount arbitrary filesystems could use this for
denial of service.

CVE-2018-1108

Jann Horn reported that crng_ready() does not properly handle the
crng_init variable states and the RNG could be treated as
cryptographically safe too early after system boot.

CVE-2018-5803

Alexey Kodanev reported that the SCTP protocol did not range-check
the length of chunks to be created.  A local or remote user could
use this to cause a denial of service.

CVE-2018-7480

Hou Tao discovered a double-free flaw in the blkcg_init_queue()
function in block/blk-cgroup.c. A local user could use this to cause
a denial of service or have other impact.

CVE-2018-7566

Fan LongFei reported a race condition in the ALSA (sound)
sequencer core, between write and ioctl operations.  This could
lead to an out-of-bounds access or use-after-free.  A local user
with access to a sequencer device could use this for denial of
service or possibly for privilege escalation.

CVE-2018-7740

Nic Losby reported that the hugetlbfs filesystem's mmap operation
did not properly range-check the file offset.  A local user with
access to files on a hugetlbfs filesystem could use this to cause
a denial of service.

CVE-2018-7757

Jason Yan reported a memory leak in the SAS (Serial-Attached
SCSI) subsystem.  A local user on a system with SAS devices
could use this to cause a denial of service.

CVE-2018-7995

Seunghun Han reported a race condition in the x86 MCE
(Machine Check Exception) driver.  This is unlikely to have
any security impact.

CVE-2018-8087

A memory leak flaw was found in the hwsim_new_radio_nl() function in
the simulated radio testing tool driver for mac80211, allowing a
local user to cause a denial of service.

CVE-2018-8781

Eyal Itkin reported that the udl (DisplayLink) driver's mmap
operation did not properly range-check the file offset.  A local
user with access to a udl framebuffer device could exploit this to
overwrite kernel memory, leading to privilege escalation.

CVE-2018-8822

Dr Silvio Cesare of InfoSect reported that the ncpfs client
implementation did not validate reply lengths from the server.  An
ncpfs server could use this to cause a denial of service or
remote code execution in the client.

CVE-2018-10323

Wen Xu reported a NULL pointer dereference flaw in the
xfs_bmapi_write() function triggered when mounting and operating a
crafted xfs filesystem image. A local user able to mount arbitrary
filesystems could use this for denial of service.

CVE-2018-1000199

Andy Lutomirski discovered that the ptrace subsystem did not
sufficiently validate hardware breakpoint settings.  Local users
can use this to cause a denial of service, or possibly for
privilege escalation, on x86 (amd64 and i386) and possibly other
architectures.

For the stable distribution (stretch), these problems have been fixed in
version 4.9.88-1.

We recommend that you upgrade your linux packages.

For the detailed security status of linux please refer to its security
tracker page at:
https://security-tracker.debian.org/tracker/linux

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/

Mailing list: [email protected]