openpic: avoid buffer overrun on incoming migration

CVE-2013-4534

opp->nb_cpus is read from the wire and used to determine how many
IRQDest elements to read into opp->dst[]. If the value exceeds the
length of opp->dst[], MAX_CPU, opp->dst[] can be overrun with arbitrary
data from the wire.

Fix this by failing migration if the value read from the wire exceeds
MAX_CPU.

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
Michael Roth 2014-04-28 16:08:17 +03:00 committed by Juan Quintela
parent a9c380db3b
commit 73d963c0a7

View File

@ -41,6 +41,7 @@
#include "hw/sysbus.h"
#include "hw/pci/msi.h"
#include "qemu/bitops.h"
#include "qapi/qmp/qerror.h"
//#define DEBUG_OPENPIC
@ -1416,7 +1417,7 @@ static void openpic_load_IRQ_queue(QEMUFile* f, IRQQueue *q)
static int openpic_load(QEMUFile* f, void *opaque, int version_id)
{
OpenPICState *opp = (OpenPICState *)opaque;
unsigned int i;
unsigned int i, nb_cpus;
if (version_id != 1) {
return -EINVAL;
@ -1428,7 +1429,11 @@ static int openpic_load(QEMUFile* f, void *opaque, int version_id)
qemu_get_be32s(f, &opp->spve);
qemu_get_be32s(f, &opp->tfrr);
qemu_get_be32s(f, &opp->nb_cpus);
qemu_get_be32s(f, &nb_cpus);
if (opp->nb_cpus != nb_cpus) {
return -EINVAL;
}
assert(nb_cpus > 0 && nb_cpus <= MAX_CPU);
for (i = 0; i < opp->nb_cpus; i++) {
qemu_get_sbe32s(f, &opp->dst[i].ctpr);
@ -1567,6 +1572,13 @@ static void openpic_realize(DeviceState *dev, Error **errp)
{NULL}
};
if (opp->nb_cpus > MAX_CPU) {
error_set(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE,
TYPE_OPENPIC, "nb_cpus", (uint64_t)opp->nb_cpus,
(uint64_t)0, (uint64_t)MAX_CPU);
return;
}
switch (opp->model) {
case OPENPIC_MODEL_FSL_MPIC_20:
default: