MGASA-2014-0451

This kernel-linus update is based on upstream -longterm 3.14.23 and fixes the following security issues:

The kvmiommumap_pages function in virt/kvm/iommu.c in the Linux kernel through 3.16.1 miscalculates the number of pages during the handling of a mapping failure, which allows guest OS users to (1) cause a denial of service (host OS memory corruption) or possibly have unspecified other impact by triggering a large gfn value or (2) cause a denial of service (host OS memory consumption) by triggering a small gfn value that leads to permanently pinned pages (CVE-2014-3601).

The assocarraygc function in the associative-array implementation in lib/assoc_array.c in the Linux kernel before 3.16.3 does not properly implement garbage collection, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via multiple "keyctl newring" operations followed by a "keyctl timeout" operation (CVE-2014-3631).

The xfsda3fixhashpath function in fs/xfs/xfsdabtree.c in the xfs implementation in the Linux kernel before 3.14.2 does not properly compare btree hash values, which allows local users to cause a denial of service (filesystem corruption, and OOPS or panic) via operations on directories that have hash collisions, as demonstrated by rmdir operations (CVE-2014-7283).

The netgetrandom_once implementation in net/core/utils.c in the Linux kernel 3.13.x and 3.14.x before 3.14.5 on certain Intel processors does not perform the intended slow-path operation to initialize random seeds, which makes it easier for remote attackers to spoof or disrupt IP communication by leveraging the predictability of TCP sequence numbers, TCP and UDP port numbers, and IP ID values (CVE-2014-7284)

The pivotroot implementation in fs/namespace.c in the Linux kernel through 3.17 does not properly interact with certain locations of a chroot directory, which allows local users to cause a denial of service (mount-tree loop) via . (dot) values in both arguments to the pivotroot system call (CVE-2014-7970).

The doumount function in fs/namespace.c in the Linux kernel through 3.17 does not require the CAPSYSADMIN capability for doremountsb calls that change the root filesystem to read-only, which allows local users to cause a denial of service (loss of writability) by making certain unshare system calls, clearing the / MNTLOCKED flag, and making an MNT_FORCE umount system call (CVE-2014-7975).

For other fixes included in this update, read the referenced changelogs.