Correct ARP update handling when the routes for network interfaces are

restricted to a single FIB in a multifib system.

Restricting an interface's routes to the FIB to which it is assigned (by
setting net.add_addr_allfibs=0) causes ARP updates to fail with "arpresolve:
can't allocate llinfo for x.x.x.x".  This is due to the ARP update code hard
coding it's lookup for existing routing entries to FIB 0.

sys/netinet/in.c:
	When dealing with RTM_ADD (add route) requests for an interface, use
	the interface's assigned FIB instead of the default (FIB 0).

sys/netinet/if_ether.c:
	In arpresolve(), enhance error message generated when an
	lla_lookup() fails so that the interface causing the error is
	visible in logs.

tests/sys/netinet/fibs_test.sh
	Clear ATF expected error.

PR:		kern/167947
Submitted by:	Nikolay Denev <ndenev@gmail.com> (previous version)
Reviewed by:	melifaro
MFC after:	3 weeks
Sponsored by:	Spectra Logic Corporation

2 files changed, 5 insertions, 4 deletions

diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index a26e179fd987..f40c683be4e2 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -334,8 +334,8 @@ retry:
 	if (la == NULL) {
 		if (flags & LLE_CREATE)
 			log(LOG_DEBUG,
-			    "arpresolve: can't allocate llinfo for %s\n",
-			    inet_ntoa(SIN(dst)->sin_addr));
+			    "arpresolve: can't allocate llinfo for %s on %s\n",
+			    inet_ntoa(SIN(dst)->sin_addr), ifp->if_xname);
 		m_freem(m);
 		return (EINVAL);
 	}
diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index e4a54b2716de..b36d2e224ee9 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -994,8 +994,9 @@ in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr
 	KASSERT(l3addr->sa_family == AF_INET,
 	    ("sin_family %d", l3addr->sa_family));
 
-	/* XXX rtalloc1 should take a const param */
-	rt = rtalloc1(__DECONST(struct sockaddr *, l3addr), 0, 0);
+	/* XXX rtalloc1_fib should take a const param */
+	rt = rtalloc1_fib(__DECONST(struct sockaddr *, l3addr), 0, 0,
+	    ifp->if_fib);
 
 	if (rt == NULL)
 		return (EINVAL);