Security update for xen (important)

xen was updated to fix eight security issues.

These security issues were fixed:

• CVE-2015-4037: The slirp_smb function in net/slirp.c created temporary
  files with predictable names, which allowed local users to cause a
  denial of service (instantiation failure) by creating /tmp/qemu-smb.-
  files before the program (bsc#932267).
• CVE-2014-0222: Integer overflow in the qcow_open function allowed remote
  attackers to cause a denial of service (crash) via a large L2 table in a
  QCOW version 1 image (bsc#877642).
• CVE-2015-7835: Uncontrolled creation of large page mappings by PV guests
  (bsc#950367).
• CVE-2015-5239: Integer overflow in vnc_client_read() and
  protocol_client_msg() (bsc#944463).
• CVE-2015-6815: With e1000 NIC emulation support it was possible to enter
  an infinite loop (bsc#944697).
• CVE-2015-7969: Leak of main per-domain vcpu pointer array leading to
  denial of service (bsc#950703).
• CVE-2015-7969: Leak of per-domain profiling- related vcpu pointer array
  leading to denial of service (bsc#950705).
• CVE-2015-7971: Some pmu and profiling hypercalls log without rate
  limiting (bsc#950706).