From 6c352ca9b4ee3e1e286ea9e8434bd8e69ac7d0d8 Mon Sep 17 00:00:00 2001
From: Li Qiang <liqiang6-s@360.cn>
Date: Mon, 8 Aug 2016 18:08:31 +0530
Subject: [PATCH] net: vmxnet3: check for device_active before write

Vmxnet3 device emulator does not check if the device is active,
before using it for write. It leads to a use after free issue,
if the vmxnet3_io_bar0_write routine is called after the device is
deactivated. Add check to avoid it.

Reported-by: Li Qiang <liqiang6-s@360.cn>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
Acked-by: Dmitry Fleytman <dmitry@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 hw/net/vmxnet3.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hw/net/vmxnet3.c b/hw/net/vmxnet3.c
index bbf44adbcc..90f6943668 100644
--- a/hw/net/vmxnet3.c
+++ b/hw/net/vmxnet3.c
@@ -1167,6 +1167,10 @@ vmxnet3_io_bar0_write(void *opaque, hwaddr addr,
 {
     VMXNET3State *s = opaque;
 
+    if (!s->device_active) {
+        return;
+    }
+
     if (VMW_IS_MULTIREG_ADDR(addr, VMXNET3_REG_TXPROD,
                         VMXNET3_DEVICE_MAX_TX_QUEUES, VMXNET3_REG_ALIGN)) {
         int tx_queue_idx =