kernel security and bug fix update

kernel
[2.6.18-406]

• [fs] pipe: fix pipe corruption and iovec overrun on partial copy (Mateusz Guzik) [1203787] {CVE-2015-1805}
  [2.6.18-405]
• [net] tcp: zero retrans_stamp if all retrans were acked (Marcelo Leitner) [1205521]
• [net] tcp: fix retrans_stamp advancing in error cases (Marcelo Leitner) [1205521]
• [net] tcp: Fix inconsistency source (Marcelo Leitner) [1205521]
• [ipc] sem: fix the potential use-after-free in freeary() (Oleg Nesterov) [1124574]
• [scsi] lpfc: Fix crash in device reset handler (Rob Evers) [1070964]
• [mm] fix broken max_reclaims_in_progress memory reclaim throttle (Lachlan McIlroy) [1164105]
• [x86_64] fpu: save_i387() must clr TS_USEDFPU along with stts() (Oleg Nesterov) [1193505]
• [block] virtio: Call revalidate_disk() upon online disk resize (Stefan Hajnoczi) [1200855]
• [block] virtio: fix config handler race (Stefan Hajnoczi) [1200855]
• [block] virtio: allow re-reading config space at runtime (Stefan Hajnoczi) [1200855]