From: Alexander Bulekov <alxndr@bu.edu>
Date: Mon, 1 Mar 2021 14:33:43 -0500
Subject: cadence_gem: switch to use qemu_receive_packet() for loopback
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Git-commit: e73adfbeec9d4e008630c814759052ed945c3fed

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: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 hw/net/cadence_gem.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c
index 7a534691f1f43ab4fefaf2f82dc9..43b760e3f1b7fb9bf0d116361713 100644
--- a/hw/net/cadence_gem.c
+++ b/hw/net/cadence_gem.c
@@ -1275,8 +1275,8 @@ static void gem_transmit(CadenceGEMState *s)
                 /* Send the packet somewhere */
                 if (s->phy_loop || (s->regs[GEM_NWCTRL] &
                                     GEM_NWCTRL_LOCALLOOP)) {
-                    gem_receive(qemu_get_queue(s->nic), s->tx_packet,
-                                total_bytes);
+                    qemu_receive_packet(qemu_get_queue(s->nic), s->tx_packet,
+                                        total_bytes);
                 } else {
                     qemu_send_packet(qemu_get_queue(s->nic), s->tx_packet,
                                      total_bytes);