Request for stable-4.1.y stable inclusion

Hello Dave,

Could you please backport the following to stable-4.1.y:

	commit 74e98eb085889b0d2d4908f59f6e00026063014f -- RDS: verify
	the underlying transport exists before creating a connection

	This fixes CVE-2015-6937.

	commit 48900cb6af4282fa0fb6ff4d72a81aa3dadb5c39 -- virtio-net:
	drop NETIF_F_FRAGLIST

	This fixes CVE-2015-5156.

Thanks!