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[PULL,3/3] Fix total IP header length in forwarded TCP packets

Message ID 20170527214618.32626-4-samuel.thibault@ens-lyon.org
State New
Headers show

Commit Message

Samuel Thibault May 27, 2017, 9:46 p.m. UTC 
From: Sjors Gielen <sjors@sjorsgielen.nl>

When forwarding TCP packets, the internal tcpiphdr struct length was wrongly
used inside the IP header. This commit changes the behaviour to what is used
by tcp_output.c, using the correct full IP header + payload length.

Signed-off-by: Sjors Gielen <sjors@sjorsgielen.nl>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
---
 slirp/tcp_subr.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c
index ed16e1807f..dc8b4bbb50 100644
--- a/slirp/tcp_subr.c
+++ b/slirp/tcp_subr.c
@@ -204,7 +204,7 @@  tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m,
 	    m->m_len  -= sizeof(struct tcpiphdr) - sizeof(struct tcphdr)
 	                                         - sizeof(struct ip);
 	    ip = mtod(m, struct ip *);
-	    ip->ip_len = tlen;
+	    ip->ip_len = m->m_len;
 	    ip->ip_dst = tcpiph_save.ti_dst;
 	    ip->ip_src = tcpiph_save.ti_src;
 	    ip->ip_p = tcpiph_save.ti_pr;
@@ -224,7 +224,7 @@  tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m,
 	    m->m_len  -= sizeof(struct tcpiphdr) - sizeof(struct tcphdr)
 	                                         - sizeof(struct ip6);
 	    ip6 = mtod(m, struct ip6 *);
-	    ip6->ip_pl = tlen;
+	    ip6->ip_pl = tcpiph_save.ti_len;
 	    ip6->ip_dst = tcpiph_save.ti_dst6;
 	    ip6->ip_src = tcpiph_save.ti_src6;
 	    ip6->ip_nh = tcpiph_save.ti_nh6;