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_TEST hook. Reported-by: Anthony Liguori <anth...@codemonkey.ws> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> --- hw/timer/hpet.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c index 1ee0640..67671bc 100644 --- a/hw/timer/hpet.c +++ b/hw/timer/hpet.c @@ -248,6 +248,22 @@ static int hpet_pre_load(void *opaque) return 0; } +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 bool hpet_fix_num_timers(HPETState *s) +{ +} + static int hpet_post_load(void *opaque, int version_id) { HPETState *s = opaque; @@ -318,6 +334,7 @@ static const VMStateDescription vmstate_hpet = { VMSTATE_UINT64(isr, HPETState), VMSTATE_UINT64(hpet_counter, HPETState), VMSTATE_UINT8_V(num_timers, HPETState, 2), + VMSTATE_TEST("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