CVE-2013-4527 hw/timer/hpet.c buffer overrun
hpet is a VARRAY with a uint8 size but static array of 32
To fix, make sure num_timers is valid using VMSTATE_VALID hook.
Reported-by: Anthony Liguori <anth...@codemonkey.ws>
Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
---
hw/timer/hpet.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
index e15d6bc..2792f89 100644
--- a/hw/timer/hpet.c
+++ b/hw/timer/hpet.c
@@ -239,6 +239,18 @@ static int hpet_pre_load(void *opaque)
return 0;
}
+static bool hpet_validate_num_timers(void *opaque, int version_id)
+{
+ HPETState *s = opaque;
+
+ if (s->num_timers < HPET_MIN_TIMERS) {
+ return false;
+ } else if (s->num_timers > HPET_MAX_TIMERS) {
+ return false;
+ }
+ return true;
+}
+
static int hpet_post_load(void *opaque, int version_id)
{
HPETState *s = opaque;
@@ -307,6 +319,7 @@ static const VMStateDescription vmstate_hpet = {
VMSTATE_UINT64(isr, HPETState),
VMSTATE_UINT64(hpet_counter, HPETState),
VMSTATE_UINT8_V(num_timers, HPETState, 2),
+ VMSTATE_VALIDATE("num_timers in range", hpet_validate_num_timers),
VMSTATE_STRUCT_VARRAY_UINT8(timer, HPETState, num_timers, 0,
vmstate_hpet_timer, HPETTimer),
VMSTATE_END_OF_LIST()
--
MST
