Commit 8357946b authored by Stefan Hajnoczi's avatar Stefan Hajnoczi
Browse files

rtl8139: check TCP Data Offset field (CVE-2015-5165) 



The TCP Data Offset field contains the length of the header.  Make sure
it is valid and does not exceed the IP data length.

Reported-by: default avatar朱东海(启路) <donghai.zdh@alibaba-inc.com>
Reviewed-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 4240be45

hw/net/rtl8139.c

+5 −0
Original line number Diff line number Diff line
@@ -2239,6 +2239,11 @@ static int rtl8139_cplus_transmit_one(RTL8139State *s) 


                int tcp_hlen = TCP_HEADER_DATA_OFFSET(p_tcp_hdr);



                /* Invalid TCP data offset? */

                if (tcp_hlen < sizeof(tcp_header) || tcp_hlen > ip_data_len) {

                    goto skip_offload;

                }



                /* ETH_MTU = ip header len + tcp header len + payload */

                int tcp_data_len = ip_data_len - tcp_hlen;

                int tcp_chunk_size = ETH_MTU - hlen - tcp_hlen;