ps2: check PS2Queue pointers in post_load routine
During Qemu guest migration, a destination process invokes ps2 post_load function. In that, if 'rptr' and 'count' values were invalid, it could lead to OOB access or infinite loop issue. Add check to avoid it. Reported-by: Cyrille Chatras <cyrille.chatras@orange.com> Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> Message-id: 20171116075155.22378-1-ppandit@redhat.com Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
parent
a5f99be41e
commit
802cbcb730
|
@ -1225,24 +1225,21 @@ static void ps2_common_reset(PS2State *s)
|
||||||
static void ps2_common_post_load(PS2State *s)
|
static void ps2_common_post_load(PS2State *s)
|
||||||
{
|
{
|
||||||
PS2Queue *q = &s->queue;
|
PS2Queue *q = &s->queue;
|
||||||
int size;
|
uint8_t i, size;
|
||||||
int i;
|
uint8_t tmp_data[PS2_QUEUE_SIZE];
|
||||||
int tmp_data[PS2_QUEUE_SIZE];
|
|
||||||
|
|
||||||
/* set the useful data buffer queue size, < PS2_QUEUE_SIZE */
|
/* set the useful data buffer queue size, < PS2_QUEUE_SIZE */
|
||||||
size = q->count > PS2_QUEUE_SIZE ? 0 : q->count;
|
size = (q->count < 0 || q->count > PS2_QUEUE_SIZE) ? 0 : q->count;
|
||||||
|
|
||||||
/* move the queue elements to the start of data array */
|
/* move the queue elements to the start of data array */
|
||||||
if (size > 0) {
|
for (i = 0; i < size; i++) {
|
||||||
for (i = 0; i < size; i++) {
|
if (q->rptr < 0 || q->rptr >= sizeof(q->data)) {
|
||||||
/* move the queue elements to the temporary buffer */
|
q->rptr = 0;
|
||||||
tmp_data[i] = q->data[q->rptr];
|
|
||||||
if (++q->rptr == 256) {
|
|
||||||
q->rptr = 0;
|
|
||||||
}
|
|
||||||
}
|
}
|
||||||
memcpy(q->data, tmp_data, size);
|
tmp_data[i] = q->data[q->rptr++];
|
||||||
}
|
}
|
||||||
|
memcpy(q->data, tmp_data, size);
|
||||||
|
|
||||||
/* reset rptr/wptr/count */
|
/* reset rptr/wptr/count */
|
||||||
q->rptr = 0;
|
q->rptr = 0;
|
||||||
q->wptr = size;
|
q->wptr = size;
|
||||||
|
|
Loading…
Reference in a new issue