From 77d54985b85a0cb760330ec2bd92505e0a2a97a9 Mon Sep 17 00:00:00 2001

From: Prasad J Pandit <pjp@fedoraproject.org>

Date: Tue, 29 Nov 2016 00:38:39 +0530

Subject: [PATCH] net: mcf: check receive buffer size register value

ColdFire Fast Ethernet Controller uses a receive buffer size

register(EMRBR) to hold maximum size of all receive buffers.

It is set by a user before any operation. If it was set to be

zero, ColdFire emulator would go into an infinite loop while

receiving data in mcf_fec_receive. Add check to avoid it.

Reported-by: Wjjzhang <wjjzhang@tencent.com>

Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>

Signed-off-by: Jason Wang <jasowang@redhat.com>

---

 hw/net/mcf_fec.c |    2 +-

 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/hw/net/mcf_fec.c b/hw/net/mcf_fec.c

index dc61bac..4025eb3 100644

--- a/hw/net/mcf_fec.c

+++ b/hw/net/mcf_fec.c

@@ -393,7 +393,7 @@ static void mcf_fec_write(void *opaque, hwaddr addr,

         s->tx_descriptor = s->etdsr;

         break;

     case 0x188:

-        s->emrbr = value & 0x7f0;

+        s->emrbr = value > 0 ? value & 0x7F0 : 0x7F0;

         break;

     default:

         hw_error("mcf_fec_write Bad address 0x%x\n", (int)addr);

-- 

1.7.0.4