MGASA-2015-0221

This kernel update is based on upstream -longterm 3.14.41 and fixes the following security issues:

net/netfilter/nfconntrackproto_generic.c in the Linux kernel before 3.18 generates incorrect conntrack entries during handling of certain iptables rule sets for the SCTP, DCCP, GRE, and UDP-Lite protocols, which allows remote attackers to bypass intended access restrictions via packets with disallowed port numbers (CVE-2014-8160).

The em_sysenter function in arch/x86/kvm/emulate.c in the Linux kernel before 3.18.5, when the guest OS lacks SYSENTER MSR initialization, allows guest OS users to gain guest OS privileges or cause a denial of service (guest OS crash) by triggering use of a 16-bit code segment for emulation of a SYSENTER instruction (CVE-2015-0239).

It was found that the Linux kernel's ping socket implementation didn't properly handle socket unhashing during spurious disconnects which could lead to use-after-free flaw. On x86-64 architecture systems, a local user able to create ping sockets could use this flaw to crash the system. On non-x86-64 architecture systems, a local user able to create ping sockets could use this flaw to increase their privileges on the system. Note: By default ping sockets are disabled on the system (net.ipv4.pinggrouprange = 1 0) and have to be explicitly enabled by the system administrator for specific user groups in order to exploit this issue (CVE-2015-3636).

For other fixes in this update, see the referenced changelogs.