svn commit: r305407 - head/sys/dev/hyperv/netvsc

[Sepherosa Ziehau]

Author: sephe
Date: Mon Sep  5 03:39:04 2016
New Revision: 305407
URL: https://svnweb.freebsd.org/changeset/base/305407

Log:
  hyperv/hn: Stringent NVS notification length check.
  
  MFC after:	1 week
  Sponsored by:	Microsoft
  Differential Revision:	https://reviews.freebsd.org/D7753

Modified:
  head/sys/dev/hyperv/netvsc/hv_net_vsc.c

Modified: head/sys/dev/hyperv/netvsc/hv_net_vsc.c
==============================================================================
--- head/sys/dev/hyperv/netvsc/hv_net_vsc.c	Mon Sep  5 03:37:28 2016	(r305406)
+++ head/sys/dev/hyperv/netvsc/hv_net_vsc.c	Mon Sep  5 03:39:04 2016	(r305407)
@@ -816,7 +816,12 @@ hn_proc_notify(struct hn_softc *sc, cons
 {
 	const struct hn_nvs_hdr *hdr;
 
+	if (VMBUS_CHANPKT_DATALEN(pkt) < sizeof(*hdr)) {
+		if_printf(sc->hn_ifp, "invalid nvs notify\n");
+		return;
+	}
 	hdr = VMBUS_CHANPKT_CONST_DATA(pkt);
+
 	if (hdr->nvs_type == HN_NVS_TYPE_TXTBL_NOTE) {
 		/* Useless; ignore */
 		return;