From: Patrick McHardy Date: Mon, 16 May 2011 12:45:39 +0000 (+0200) Subject: netfilter: nf_ct_sip: fix SDP parsing in TCP SIP messages for some Cisco phones X-Git-Tag: v2.6.39.1~114 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=6406426e95eea9ccfcc8b15ac6613c8af438cffe;p=karo-tx-linux.git netfilter: nf_ct_sip: fix SDP parsing in TCP SIP messages for some Cisco phones [ Upstream commit e6e4d9ed11fb1fab8b3256a3dc14d71b5e984ac4 ] Some Cisco phones do not place the Content-Length field at the end of the SIP message. This is valid, due to a misunderstanding of the specification the parser expects the SDP body to start directly after the Content-Length field. Fix the parser to scan for \r\n\r\n to locate the beginning of the SDP body. Reported-by: Teresa Kang Signed-off-by: Patrick McHardy Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c index 3fed15e82512..cb5a28581782 100644 --- a/net/netfilter/nf_conntrack_sip.c +++ b/net/netfilter/nf_conntrack_sip.c @@ -1419,6 +1419,7 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff, const char *dptr, *end; s16 diff, tdiff = 0; int ret = NF_ACCEPT; + bool term; typeof(nf_nat_sip_seq_adjust_hook) nf_nat_sip_seq_adjust; if (ctinfo != IP_CT_ESTABLISHED && @@ -1453,10 +1454,15 @@ static int sip_help_tcp(struct sk_buff *skb, unsigned int protoff, if (dptr + matchoff == end) break; - if (end + strlen("\r\n\r\n") > dptr + datalen) - break; - if (end[0] != '\r' || end[1] != '\n' || - end[2] != '\r' || end[3] != '\n') + term = false; + for (; end + strlen("\r\n\r\n") <= dptr + datalen; end++) { + if (end[0] == '\r' && end[1] == '\n' && + end[2] == '\r' && end[3] == '\n') { + term = true; + break; + } + } + if (!term) break; end += strlen("\r\n\r\n") + clen;