rtl8139: fix possible out of bound access

In rtl8139_do_receive(), we try to assign size_ to size which converts
from size_t to integer. This will cause troubles when size_ is greater
INT_MAX, this will lead a negative value in size and it can then pass
the check of size < MIN_BUF_SIZE which may lead out of bound access of
for both buf and buf1.

Fixing by converting the type of size to size_t.

CC: qemu-stable@nongnu.org
Reported-by: Daniel Shapira <daniel@twistlock.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This commit is contained in:
Jason Wang 2018-05-30 13:07:43 +08:00
parent fdc89e90fa
commit 1a326646fe

View File

@ -817,7 +817,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t
RTL8139State *s = qemu_get_nic_opaque(nc);
PCIDevice *d = PCI_DEVICE(s);
/* size is the length of the buffer passed to the driver */
int size = size_;
size_t size = size_;
const uint8_t *dot1q_buf = NULL;
uint32_t packet_header = 0;
@ -826,7 +826,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t
static const uint8_t broadcast_macaddr[6] =
{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
DPRINTF(">>> received len=%d\n", size);
DPRINTF(">>> received len=%zu\n", size);
/* test if board clock is stopped */
if (!s->clock_enabled)
@ -1035,7 +1035,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t
if (size+4 > rx_space)
{
DPRINTF("C+ Rx mode : descriptor %d size %d received %d + 4\n",
DPRINTF("C+ Rx mode : descriptor %d size %d received %zu + 4\n",
descriptor, rx_space, size);
s->IntrStatus |= RxOverflow;
@ -1148,7 +1148,7 @@ static ssize_t rtl8139_do_receive(NetClientState *nc, const uint8_t *buf, size_t
if (avail != 0 && RX_ALIGN(size + 8) >= avail)
{
DPRINTF("rx overflow: rx buffer length %d head 0x%04x "
"read 0x%04x === available 0x%04x need 0x%04x\n",
"read 0x%04x === available 0x%04x need 0x%04zx\n",
s->RxBufferSize, s->RxBufAddr, s->RxBufPtr, avail, size + 8);
s->IntrStatus |= RxOverflow;