slirp: don't zero the whole ti_i when m == NULL

98c63057d2 ('slirp: Factorizing
tcpiphdr structure with an union') introduced a memset call to clear
possibly-undefined fields in ti. This however overwrites src/dst/pr which
are used below.

So let us clear only the unused fields.

This should fix some rare cases (some RST cases, keep alive probes)
where packets would be sent to 0.0.0.0.

Signed-off-by: Tao Wu <lepton@google.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
This commit is contained in:
Tao Wu 2017-11-08 14:53:40 -08:00 committed by Samuel Thibault
parent b0fbe46ad8
commit 990132cda9
1 changed files with 10 additions and 1 deletions

View File

@ -148,7 +148,16 @@ tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m,
m->m_data += IF_MAXLINKHDR;
*mtod(m, struct tcpiphdr *) = *ti;
ti = mtod(m, struct tcpiphdr *);
memset(&ti->ti, 0, sizeof(ti->ti));
switch (af) {
case AF_INET:
ti->ti.ti_i4.ih_x1 = 0;
break;
case AF_INET6:
ti->ti.ti_i6.ih_x1 = 0;
break;
default:
g_assert_not_reached();
}
flags = TH_ACK;
} else {
/*