SUSE-SU-2018:2474-1

This update for the Linux Kernel 4.12.14-23 fixes several issues.

The following security issues were fixed:

• CVE-2018-5390: Linux kernel versions 4.9+ can be forced to make very expensive calls to tcpcollapseofoqueue() and tcppruneofoqueue() for every incoming packet which can lead to a denial of service (bsc#1102682).
• CVE-2018-3646: Local attackers in virtualized guest systems could use speculative code patterns on hyperthreaded processors to read data present in the L1 Datacache used by other hyperthreads on the same CPU core, potentially leaking sensitive data, even from other virtual machines or the host system (bsc#1099306).
• CVE-2017-18344: The timercreate syscall implementation in kernel/time/posix-timers.c didn't properly validate the sigevent->sigevnotify field, which lead to out-of-bounds access in the showtimer function (called when /proc/$PID/timers is read). This allowed userspace applications to read arbitrary kernel memory (on a kernel built with CONFIGPOSIXTIMERS and CONFIGCHECKPOINT_RESTORE) (bsc#1103203). before 4.14.8
• CVE-2018-12904: In arch/x86/kvm/vmx.c local attackers could cause L1 KVM guests to VMEXIT, potentially allowing privilege escalations and denial of service attacks due to lack of checking of CPL (bsc#1099258).
• CVE-2018-10853: A flaw was found in kvm. In which certain instructions such as sgdt/sidt call segmentedwritestd didn't propagate access correctly. As such, during userspace induced exception, the guest can incorrectly assume that the exception happened in the kernel and panic. (bsc#1097108).