RHEL 7 : kernel (RHSA-2017:2770)

high Nessus Plugin ID 103351

Synopsis

The remote Red Hat host is missing a security update for kernel.

Description

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2017:2770 advisory.

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

* A race condition was found in the Linux kernel, present since v3.14-rc1 through v4.12. The race happens between threads of inotify_handle_event() and vfs_rename() while running the rename operation against the same file. As a result of the race the next slab data or the slab's free list pointer can be corrupted with attacker-controlled data, which may lead to the privilege escalation. (CVE-2017-7533, Important)

Red Hat would like to thank Leilei Lin (Alibaba Group), Fan Wu (The University of Hong Kong), and Shixiong Zhao (The University of Hong Kong) for reporting this issue.

Bug Fix(es):

* Previously, the sha1-avx2 optimized hashing, which is used on processors supporting avx2, under certain conditions miscalculated an offset. Consequently, a kernel crash occasionally occurred on the NFS clients or servers using the krb5 security. With this update, the optimized hashing path for sha1-avx2 has been disabled, and the NFS clients and servers with krb5 security no longer experience the miscalculation and subsequent crash. (BZ#1446230)

* When virt boundary limit was set, lots of small bios could not be merged even though they were contiguous physically. In some workload, such as mkfs.ntfs, system performance could be ten times degraded. The proposed patch fixes the bug by allowing to merge these small bios, which improves performance of mkfs.ntfs on devices significantly. (BZ#1472674)

* When executing the mkfs.btrfs command to create a btrfs file system over Non-Volatile Memory Express (NVMe), kernel panic was previously triggered. The underlying code has been patched to fix this regression, and btrfs is now created successfully in the described scenario. (BZ#1472675)

* As a side effect of BZ#147263, the system previously crashed when creating a container device. The provided patch transforms the resched_task() function into resched_curr(), and the chance of kernel crash is thus reduced in the aforementioned situation. (BZ#1473742)

* Due to incorrectly used memory in VXLAN driver (a use-after-free bug and list corruption), the kernel could previously panic under some circumstances while bringing the VXLAN interfaces down. The provided patch fixes the memory corruptions, and the panic no longer occurs in this situation. (BZ#1474263)

* A race condition could cause the in-flight asynchronous buffers count (bt_io_count) to become negative.
This caused the umount operation to hang in the xfs_wait_buftarg() function. The provided patch fixes the buffer I/O accounting release race, and XFS umount no longer hangs. (BZ#1478253)

* Kernel version 3.10.0-498.el7 separated CPU and TSC frequency and introduced the x86_platform.calibrate_cpu function pointer which points by default to the native_calibrate_cpu() function. As a consequence, time synchronization bugs appeared on Red Hat Enterprise Linux 7.3 ESXi guest causing a time offset shortly after boot. An upstream patch has been applied, which sets x86_platform.calibrate_cpu pointer on ESXi guests to the proper function, thus fixing this bug.
(BZ#1479245)

* A system having more than 128 CPUs could previously experience a crash during shutdown after the Intelligent Platform Management Interface (IPMI) service was stopped. The provided patch fixes a race condition in the IPMI smi_timeout() function, allowing the system to shut down as expected. (BZ#1479760)

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the RHEL kernel package based on the guidance in RHSA-2017:2770.

See Also

http://www.nessus.org/u?f476aeba

https://access.redhat.com/errata/RHSA-2017:2770

https://access.redhat.com/security/updates/classification/#important

https://bugzilla.redhat.com/show_bug.cgi?id=1468283

Plugin Details

Severity: High

ID: 103351

File Name: redhat-RHSA-2017-2770.nasl

Version: 3.12

Type: local

Agent: unix

Published: 9/20/2017

Updated: 11/5/2024

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: Medium

Base Score: 6.9

Temporal Score: 5.4

Vector: CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2017-7533

CVSS v3

Risk Factor: High

Base Score: 7

Temporal Score: 6.3

Vector: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:kernel-tools, p-cpe:/a:redhat:enterprise_linux:kernel, p-cpe:/a:redhat:enterprise_linux:kernel-headers, cpe:/o:redhat:rhel_eus:7.3, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs-devel, p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-kdump, p-cpe:/a:redhat:enterprise_linux:kernel-bootwrapper, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs, p-cpe:/a:redhat:enterprise_linux:python-perf, p-cpe:/a:redhat:enterprise_linux:kernel-kdump-devel, p-cpe:/a:redhat:enterprise_linux:kernel-devel, p-cpe:/a:redhat:enterprise_linux:kernel-debug, p-cpe:/a:redhat:enterprise_linux:perf

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 9/19/2017

Vulnerability Publication Date: 8/5/2017

Reference Information

CVE: CVE-2017-7533

CWE: 642

RHSA: 2017:2770