From: Stefan Hajnoczi <stefanha@redhat.com>
Date: Mon, 5 Feb 2018 12:16:00 +0000 (+0100)
Subject: vhost: validate untrusted memory regions number field
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=4d490c7ce392d4307c9ad6009729a8279646cf6c;p=dpdk.git

vhost: validate untrusted memory regions number field

Check if memory.nregions is valid right away.  This eliminates the
possibility of bugs when memory.nregions is used later on in
vhost_user_set_mem_table().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 6db50affaf..baf58dd3a8 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -663,6 +663,12 @@ vhost_user_set_mem_table(struct virtio_net *dev, struct VhostUserMsg *pmsg)
 	uint32_t i;
 	int fd;
 
+	if (memory.nregions > VHOST_MEMORY_MAX_NREGIONS) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"too many memory regions (%u)\n", memory.nregions);
+		return -1;
+	}
+
 	if (dev->mem && !vhost_memory_changed(&memory, dev->mem)) {
 		RTE_LOG(INFO, VHOST_CONFIG,
 			"(%d) memory regions not changed\n", dev->vid);