diff options
| -rw-r--r-- | sys/net/rtsock.c | 46 |
1 files changed, 30 insertions, 16 deletions
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c index 6c79d2e9b71..633134f9f6e 100644 --- a/sys/net/rtsock.c +++ b/sys/net/rtsock.c @@ -1,4 +1,4 @@ -/* $OpenBSD: rtsock.c,v 1.195 2016/08/22 16:01:52 mpi Exp $ */ +/* $OpenBSD: rtsock.c,v 1.196 2016/08/23 13:07:26 mpi Exp $ */ /* $NetBSD: rtsock.c,v 1.18 1996/03/29 00:32:10 cgd Exp $ */ /* @@ -98,7 +98,7 @@ struct walkarg { int route_ctloutput(int, struct socket *, int, int, struct mbuf **); void route_input(struct mbuf *m0, ...); -int route_arp_conflict(struct rt_addrinfo *, unsigned int); +int route_arp_conflict(struct rtentry *, struct rt_addrinfo *); int route_cleargateway(struct rtentry *, void *, unsigned int); struct mbuf *rt_msg1(int, struct rt_addrinfo *); @@ -454,7 +454,7 @@ route_output(struct mbuf *m, ...) struct rtentry *rt = NULL; struct rtentry *saved_nrt = NULL; struct rt_addrinfo info; - int plen, len, newgate, error = 0; + int plen, len, newgate = 0, error = 0; struct ifnet *ifp = NULL; struct ifaddr *ifa = NULL; struct socket *so; @@ -602,8 +602,25 @@ route_output(struct mbuf *m, ...) error = EINVAL; goto flush; } - if ((error = route_arp_conflict(&info, tableid))) + + rt = rtalloc(info.rti_info[RTAX_DST], 0, tableid); + if ((error = route_arp_conflict(rt, &info))) { + rtfree(rt); + rt = NULL; goto flush; + } + + /* + * We cannot go through a delete/create/insert cycle for + * cached route because this can lead to races in the + * receive path. Instead we upade the L2 cache. + */ + if ((rt != NULL) && ISSET(rt->rt_flags, RTF_CACHED)) + goto change; + + rtfree(rt); + rt = NULL; + error = rtrequest(RTM_ADD, &info, prio, &saved_nrt, tableid); if (error == 0) { rt_setmetrics(rtm->rtm_inits, &rtm->rtm_rmx, @@ -755,7 +772,6 @@ report: break; case RTM_CHANGE: - newgate = 0; if (info.rti_info[RTAX_GATEWAY] != NULL) if (rt->rt_gateway == NULL || bcmp(rt->rt_gateway, @@ -791,6 +807,7 @@ report: #endif } } +change: if (info.rti_info[RTAX_GATEWAY] != NULL && (error = rt_setgate(rt, info.rti_info[RTAX_GATEWAY], tableid))) @@ -936,35 +953,32 @@ route_cleargateway(struct rtentry *rt, void *arg, unsigned int rtableid) * (priv) and a public one (pub). */ int -route_arp_conflict(struct rt_addrinfo *info, unsigned int tableid) +route_arp_conflict(struct rtentry *rt, struct rt_addrinfo *info) { #if defined(ART) && !defined(SMALL_KERNEL) - struct rtentry *rt; int proxy = (info->rti_flags & RTF_ANNOUNCE); if ((info->rti_flags & RTF_LLINFO) == 0 || (info->rti_info[RTAX_DST]->sa_family != AF_INET)) return (0); - rt = rtalloc(info->rti_info[RTAX_DST], 0, tableid); - if (rt == NULL || !ISSET(rt->rt_flags, RTF_LLINFO)) { - rtfree(rt); + if (rt == NULL || !ISSET(rt->rt_flags, RTF_LLINFO)) + return (0); + + /* If the entry is cached, it can be updated. */ + if (ISSET(rt->rt_flags, RTF_CACHED)) return (0); - } /* - * Same destination and both "priv" or "pub" conflict. + * Same destination, not cached and both "priv" or "pub" conflict. * If a second entry exists, it always conflict. */ if ((ISSET(rt->rt_flags, RTF_ANNOUNCE) == proxy) || - (rtable_mpath_next(rt) != NULL)) { - rtfree(rt); + (rtable_mpath_next(rt) != NULL)) return (EEXIST); - } /* No conflict but an entry exist so we need to force mpath. */ info->rti_flags |= RTF_MPATH; - rtfree(rt); #endif /* ART && !SMALL_KERNEL */ return (0); } |