The XFS_IS_REALTIME_INODE macro in fs/xfs/xfs_linux.h in the Linux kernel before 4.13.2 does not verify that a filesystem has a realtime device, which allows local users to cause a denial of service (NULL pointer dereference and OOPS) via vectors related to setting an RHINHERIT flag on a directory.

Affected: Ubuntu:16.04:LTS: linux-hwe

USN-3468-1 fixed vulnerabilities in the Linux kernel for Ubuntu 17.04. This update provides the corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 17.04 for Ubuntu 16.04 LTS.

It was discovered that the KVM subsystem in the Linux kernel did not properly bound guest IRQs. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2017-1000252)

It was discovered that the Flash-Friendly File System (f2fs) implementation in the Linux kernel did not properly validate superblock metadata. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-10663)

Anthony Perard discovered that the Xen virtual block driver did not properly initialize some data structures before passing them to user space. A local attacker in a guest VM could use this to expose sensitive information from the host OS or other guest VMs. (CVE-2017-10911)

It was discovered that a use-after-free vulnerability existed in the POSIX message queue implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2017-11176)

Dave Chinner discovered that the XFS filesystem did not enforce that the realtime inode flag was settable only on filesystems on a realtime device. A local attacker could use this to cause a denial of service (system crash). (CVE-2017-14340)