d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix ip_output() on point-to-point links

Browse Source 
In r304435, ip_output() was changed to use the result of the route
lookup to decide whether the outgoing packet was a broadcast or
not.  This introduced a regression on interfaces where
IFF_BROADCAST was not set (e.g. point-to-point links), as the
algorithm could incorrectly treat the destination address as a
broadcast address, and ip_output() would subsequently drop the
packet as broadcasting on a non-IFF_BROADCAST interface is not
allowed.

Differential Revision:	https://reviews.freebsd.org/D8303
Reviewed by:	jtl
Reported by:	ambrisko
MFC after:	2 weeks
X-MFC-With:	r304435
Sponsored by:	Dell EMC Isilon
This commit is contained in:
Ryan Stone 2016-10-24 22:11:33 +00:00
parent f5355fadf7
commit 6c1bd55875
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=307887
1 changed files with 5 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
sys/netinet/ip_output.c
View File

@ -350,7 +350,8 @@ ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
have_ia_ref = 1;
ifp = ia->ia_ifp;
ip->ip_ttl = 1;
isbroadcast = in_ifaddr_broadcast(dst->sin_addr, ia);
isbroadcast = ifp->if_flags & IFF_BROADCAST ?
in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
} else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
imo != NULL && imo->imo_multicast_ifp != NULL) {
/*
@ -403,8 +404,10 @@ ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
gw = (struct sockaddr_in *)rte->rt_gateway;
if (rte->rt_flags & RTF_HOST)
isbroadcast = (rte->rt_flags & RTF_BROADCAST);
else
else if (ifp->if_flags & IFF_BROADCAST)
isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
else
isbroadcast = 0;
}
/*