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>
diff --git a/hw/net/ne2000.c b/hw/net/ne2000.c
index e408083..f0feaf9 100644
--- a/hw/net/ne2000.c
+++ b/hw/net/ne2000.c
@@ -155,6 +155,10 @@
{
int avail, index, boundary;
+ if (s->stop <= s->start) {
+ return 1;
+ }
+
index = s->curpag << 8;
boundary = s->boundary << 8;
if (index < boundary)
