From 6c79ea275d72bc1fd88bdcf1e7d231b2c9c865de Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Wed, 15 Jul 2015 18:17:02 +0100 Subject: [PATCH 5/7] rtl8139: check IP Total Length field The IP Total Length field includes the IP header and data. Make sure it is valid and does not exceed the Ethernet payload size. Signed-off-by: Stefan Hajnoczi --- hw/net/rtl8139.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/hw/net/rtl8139.c b/hw/net/rtl8139.c index cd5ac05..ed2b23b 100644 --- a/hw/net/rtl8139.c +++ b/hw/net/rtl8139.c @@ -2205,7 +2205,12 @@ static int rtl8139_cplus_transmit_one(RTL8139State *s) } ip_protocol = ip->ip_p; - ip_data_len = be16_to_cpu(ip->ip_len) - hlen; + + ip_data_len = be16_to_cpu(ip->ip_len); + if (ip_data_len < hlen || ip_data_len > eth_payload_len) { + goto skip_offload; + } + ip_data_len -= hlen; if (txdw0 & CP_TX_IPCS) { -- 2.1.4