From b974d27de014b3ea652caa4ea60bafbf3f65b14f Mon Sep 17 00:00:00 2001 From: ae Date: Wed, 24 May 2017 09:03:46 +0000 Subject: MFC r318399: Set M_BCAST and M_MCAST flags on mbuf sent via divert socket. r290383 has changed how mbufs sent by divert socket are handled. Previously they are always handled by slow path processing in ip_input(). Now ip_tryforward() is invoked from ip_input() before in_broadcast() check. Since diverted packet lost all mbuf flags, it passes the broadcast check in ip_tryforward() due to missing M_BCAST flag. In the result the broadcast packet is forwarded to the wire instead of be consumed by network stack. Add in_broadcast() check to the div_output() function. And restore the M_BCAST flag if destination address is broadcast for the given network interface. PR: 209491 --- sys/netinet/ip_divert.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/sys/netinet/ip_divert.c b/sys/netinet/ip_divert.c index 4d4572f..fcb7c3e 100644 --- a/sys/netinet/ip_divert.c +++ b/sys/netinet/ip_divert.c @@ -489,6 +489,14 @@ div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin, /* Send packet to input processing via netisr */ switch (ip->ip_v) { case IPVERSION: + /* + * Restore M_BCAST flag when destination address is + * broadcast. It is expected by ip_tryforward(). + */ + if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) + m->m_flags |= M_MCAST; + else if (in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) + m->m_flags |= M_BCAST; netisr_queue_src(NETISR_IP, (uintptr_t)so, m); break; #ifdef INET6 -- cgit v1.1