USN-3168-1: Linux kernel vulnerabilities

11 January 2017

Several security issues were fixed in the kernel.

Releases

Packages

  • linux - Linux kernel

Details

Dmitry Vyukov discovered that the KVM implementation in the Linux kernel
did not properly initialize the Code Segment (CS) in certain error cases. A
local attacker could use this to expose sensitive information (kernel
memory). (CVE-2016-9756)

Andrey Konovalov discovered that signed integer overflows existed in the
setsockopt() system call when handling the SO_SNDBUFFORCE and
SO_RCVBUFFORCE options. A local attacker with the CAP_NET_ADMIN capability
could use this to cause a denial of service (system crash or memory
corruption). (CVE-2016-9793)

Baozeng Ding discovered a race condition that could lead to a use-after-
free in the Advanced Linux Sound Architecture (ALSA) subsystem of the Linux
kernel. A local attacker could use this to cause a denial of service
(system crash). (CVE-2016-9794)

Baozeng Ding discovered a double free in the netlink_dump() function in the
Linux kernel. A local attacker could use this to cause a denial of service
(system crash). (CVE-2016-9806)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 14.04

After a standard system update you need to reboot your computer to make
all the necessary changes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.

Related notices

  • USN-3169-2: linux-image-generic-lts-xenial, linux-image-powerpc64-smp-lts-xenial, linux-image-4.4.0-59-lowlatency, linux-image-powerpc64-emb-lts-xenial, linux-image-lowlatency-lts-xenial, linux-lts-xenial, linux-image-powerpc-smp-lts-xenial, linux-image-4.4.0-59-powerpc-e500mc, linux-image-4.4.0-59-generic, linux-image-powerpc-e500mc-lts-xenial, linux-image-4.4.0-59-powerpc-smp, linux-image-generic-lpae-lts-xenial, linux-image-4.4.0-59-powerpc64-emb, linux-image-4.4.0-59-powerpc64-smp, linux-image-4.4.0-59-generic-lpae
  • USN-3167-1: linux-image-3.2.0-120-generic, linux-image-3.2.0-120-highbank, linux-image-3.2.0-120-virtual, linux-image-3.2.0-120-generic-pae, linux-image-3.2.0-120-powerpc64-smp, linux-image-3.2.0-120-powerpc-smp, linux-image-powerpc-smp, linux-image-generic, linux-image-powerpc64-smp, linux-image-virtual, linux-image-omap, linux-image-3.2.0-120-omap, linux, linux-image-generic-pae, linux-image-highbank
  • USN-3169-4: linux-image-snapdragon, linux-snapdragon, linux-image-4.4.0-1044-snapdragon
  • USN-3167-2: linux-image-omap4, linux-image-3.2.0-1498-omap4, linux-ti-omap4
  • USN-3170-1: linux-image-lowlatency, linux-image-generic-lpae, linux-image-4.8.0-34-powerpc64-emb, linux-image-generic, linux-image-4.8.0-34-generic, linux-image-powerpc-smp, linux-image-4.8.0-34-powerpc-e500mc, linux-image-4.8.0-34-generic-lpae, linux-image-powerpc64-emb, linux, linux-image-powerpc-e500mc, linux-image-4.8.0-34-powerpc-smp, linux-image-4.8.0-34-lowlatency
  • USN-3169-1: linux-image-lowlatency, linux-image-powerpc-smp, linux-image-powerpc64-smp, linux-image-4.4.0-59-lowlatency, linux-image-generic, linux-image-powerpc64-emb, linux-image-4.4.0-59-powerpc-smp, linux, linux-image-4.4.0-59-generic, linux-image-4.4.0-59-powerpc-e500mc, linux-image-powerpc-e500mc, linux-image-4.4.0-59-powerpc64-emb, linux-image-4.4.0-59-powerpc64-smp, linux-image-4.4.0-59-generic-lpae, linux-image-generic-lpae
  • USN-3168-2: linux-image-3.13.0-107-generic-lpae, linux-image-generic-lts-trusty, linux-image-generic-lpae-lts-trusty, linux-image-3.13.0-107-generic, linux-lts-trusty
  • USN-3170-2: linux-image-4.8.0-1022-raspi2, linux-raspi2, linux-image-raspi2
  • USN-3169-3: linux-raspi2, linux-image-4.4.0-1040-raspi2, linux-image-raspi2