msf2-mac: switch to use qemu_receive_packet() for loopback

This patch switches to use qemu_receive_packet() which can detect
reentrancy and return early.

This is intended to address CVE-2021-3416.

Cc: Prasad J Pandit <ppandit@redhat.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

diff --git a/hw/net/msf2-emac.c b/hw/net/msf2-emac.c
index 32ba9e84124496fe22f165095d61b675ed71d805..3e6206044f8b441c9222f28cc1ec6d00d807dea8 100644 (file)
--- a/hw/net/msf2-emac.c
+++ b/hw/net/msf2-emac.c
@@ -158,7 +158,7 @@ static void msf2_dma_tx(MSF2EmacState *s)
          * R_CFG1 bit 0 is set.
          */
         if (s->regs[R_CFG1] & R_CFG1_LB_EN_MASK) {
-            nc->info->receive(nc, buf, size);
+            qemu_receive_packet(nc, buf, size);
         } else {
             qemu_send_packet(nc, buf, size);
         }