From 6da8eb04ef869e8754805f7316b95d0c03a8ccd0 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Thu, 30 Jul 2015 14:34:52 +0200 Subject: [PATCH 5/7] rtl8139: check IP Total Length field (CVE-2015-5165) Message-id: <1438266894-23344-6-git-send-email-stefanha@redhat.com> Patchwork-id: 67226 O-Subject: [virt-devel] [RHEV-7.1.z qemu-kvm-rhev EMBARGOED PATCH 5/7] rtl8139: check IP Total Length field (CVE-2015-5165) Bugzilla: 1248768 RH-Acked-by: Dr. David Alan Gilbert RH-Acked-by: Xiao Wang RH-Acked-by: Michael S. Tsirkin 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 9890333..22aef55 100644 --- a/hw/net/rtl8139.c +++ b/hw/net/rtl8139.c @@ -2191,7 +2191,12 @@ 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