From 32e2f1ebf0d979c5ccc7e934ea9729e956d6aa52 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Fri, 31 Jul 2015 15:59:46 +0200 Subject: [PATCH 5/7] rtl8139: check IP Total Length field (CVE-2015-5165) Message-id: <1438358388-10575-6-git-send-email-stefanha@redhat.com> Patchwork-id: 67240 O-Subject: [RHEL-7.1.z qemu-kvm EMBARGOED PATCH 5/7] rtl8139: check IP Total Length field (CVE-2015-5165) Bugzilla: 1248764 RH-Acked-by: Dr. David Alan Gilbert RH-Acked-by: Xiao Wang RH-Acked-by: Laszlo Ersek 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 Signed-off-by: Miroslav Rezanina --- 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 7efc0b5..61bc34c 100644 --- a/hw/net/rtl8139.c +++ b/hw/net/rtl8139.c @@ -2183,7 +2183,12 @@ 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) { -- 1.8.3.1