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Revision 0447378a4a793da008451fad50bc0f93e9675ae6 authored by Marc Orr on 21 June 2018, 00:21:29 UTC, committed by Radim Krčmář on 22 June 2018, 14:46:26 UTC 
kvm: vmx: Nested VM-entry prereqs for event inj.
 
This patch extends the checks done prior to a nested VM entry.
Specifically, it extends the check_vmentry_prereqs function with checks
for fields relevant to the VM-entry event injection information, as
described in the Intel SDM, volume 3.

This patch is motivated by a syzkaller bug, where a bad VM-entry
interruption information field is generated in the VMCS02, which causes
the nested VM launch to fail. Then, KVM fails to resume L1.

While KVM should be improved to correctly resume L1 execution after a
failed nested launch, this change is justified because the existing code
to resume L1 is flaky/ad-hoc and the test coverage for resuming L1 is
sparse.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Marc Orr <marcorr@google.com>
[Removed comment whose parts were describing previous revisions and the
 rest was obvious from function/variable naming. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
1 parent 5f9077c
Raw File
p8023.c 
/*
 *	NET3:	802.3 data link hooks used for IPX 802.3
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 *
 *	802.3 isn't really a protocol data link layer. Some old IPX stuff
 *	uses it however. Note that there is only one 802.3 protocol layer
 *	in the system. We don't currently support different protocols
 *	running raw 802.3 on different devices. Thankfully nobody else
 *	has done anything like the old IPX.
 */

#include <linux/in.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/slab.h>

#include <net/datalink.h>
#include <net/p8022.h>

/*
 *	Place an 802.3 header on a packet. The driver will do the mac
 *	addresses, we just need to give it the buffer length.
 */
static int p8023_request(struct datalink_proto *dl,
			 struct sk_buff *skb, unsigned char *dest_node)
{
	struct net_device *dev = skb->dev;

	dev_hard_header(skb, dev, ETH_P_802_3, dest_node, NULL, skb->len);
	return dev_queue_xmit(skb);
}

/*
 *	Create an 802.3 client. Note there can be only one 802.3 client
 */
struct datalink_proto *make_8023_client(void)
{
	struct datalink_proto *proto = kmalloc(sizeof(*proto), GFP_ATOMIC);

	if (proto) {
		proto->header_length = 0;
		proto->request	     = p8023_request;
	}
	return proto;
}

/*
 *	Destroy the 802.3 client.
 */
void destroy_8023_client(struct datalink_proto *dl)
{
	kfree(dl);
}

EXPORT_SYMBOL(destroy_8023_client);
EXPORT_SYMBOL(make_8023_client);

MODULE_LICENSE("GPL");
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