[Qemu-devel] [PATCH 21/32] virtio-net: only delete bh that existed

[Michael Roth]

From: Jason Wang <address@hidden>

We delete without check whether it existed during exit. This will lead NULL
pointer deference since it was created conditionally depends on guest driver
status and features. So add a check of existence before trying to delete it.

Cc: address@hidden
Signed-off-by: Jason Wang <address@hidden>
Reviewed-by: Michael S. Tsirkin <address@hidden>
Message-id: address@hidden
Signed-off-by: Anthony Liguori <address@hidden>
(cherry picked from commit fe2dafa02de4f80ab36f6e0f4ddfcd6418c03c49)

Conflicts:

        hw/net/virtio-net.c

*modified to reflect timer function names for 1.6

Signed-off-by: Michael Roth <address@hidden>
---
 hw/net/virtio-net.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index aa1880c..bb757b3 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -1600,7 +1600,7 @@ static int virtio_net_device_exit(DeviceState *qdev)
         if (q->tx_timer) {
             qemu_del_timer(q->tx_timer);
             qemu_free_timer(q->tx_timer);
-        } else {
+        } else if (q->tx_bh) {
             qemu_bh_delete(q->tx_bh);
         }
     }
-- 
1.7.9.5