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

Date: Wed, 24 Feb 2016 11:41:33 +0530

Subject: [PATCH] net: ne2000: check ring buffer control registers

Ne2000 NIC uses ring buffer of NE2000_MEM_SIZE(49152)

bytes to process network packets. Registers PSTART & PSTOP

define ring buffer size & location. Setting these registers

to invalid values could lead to infinite loop or OOB r/w

access issues. Add check to avoid it.

Reported-by: Yang Hongke <yanghongke@huawei.com>

Tested-by: Yang Hongke <yanghongke@huawei.com>

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

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

(cherry picked from commit 415ab35a441eca767d033a2702223e785b9d5190)

---

 hw/net/ne2000.c | 4 ++++

 1 file changed, 4 insertions(+)

diff --git a/hw/net/ne2000.c b/hw/net/ne2000.c

index a3dffff..995115e 100644

--- a/hw/net/ne2000.c

+++ b/hw/net/ne2000.c

@@ -154,6 +154,10 @@ static int ne2000_buffer_full(NE2000State *s)

 {

     int avail, index, boundary;

+    if (s->stop <= s->start) {

+        return 1;

+    }

+

     index = s->curpag << 8;

     boundary = s->boundary << 8;

     if (index < boundary)