svn commit: r316714 - in stable/11/sys: netinet netinet6
Mark Johnston
markj at FreeBSD.org
Tue Apr 11 18:48:19 UTC 2017
Author: markj
Date: Tue Apr 11 18:48:17 2017
New Revision: 316714
URL: https://svnweb.freebsd.org/changeset/base/316714
Log:
MFC r306829, r310286, r311695:
Lock the ND prefix list and add refcounting for prefixes.
Modified:
stable/11/sys/netinet/sctp_output.c
stable/11/sys/netinet6/in6.c
stable/11/sys/netinet6/in6_ifattach.c
stable/11/sys/netinet6/nd6.c
stable/11/sys/netinet6/nd6.h
stable/11/sys/netinet6/nd6_rtr.c
Directory Properties:
stable/11/ (props changed)
Modified: stable/11/sys/netinet/sctp_output.c
==============================================================================
--- stable/11/sys/netinet/sctp_output.c Tue Apr 11 17:36:19 2017 (r316713)
+++ stable/11/sys/netinet/sctp_output.c Tue Apr 11 18:48:17 2017 (r316714)
@@ -13775,6 +13775,7 @@ sctp_v6src_match_nexthop(struct sockaddr
return (0);
/* get prefix entry of address */
+ ND6_RLOCK();
LIST_FOREACH(pfx, &MODULE_GLOBAL(nd_prefix), ndpr_entry) {
if (pfx->ndpr_stateflags & NDPRF_DETACHED)
continue;
@@ -13784,6 +13785,7 @@ sctp_v6src_match_nexthop(struct sockaddr
}
/* no prefix entry in the prefix list */
if (pfx == NULL) {
+ ND6_RUNLOCK();
SCTPDBG(SCTP_DEBUG_OUTPUT2, "No prefix entry for ");
SCTPDBG_ADDR(SCTP_DEBUG_OUTPUT2, (struct sockaddr *)src6);
return (0);
@@ -13805,9 +13807,11 @@ sctp_v6src_match_nexthop(struct sockaddr
if (sctp_cmpaddr((struct sockaddr *)&gw6, ro->ro_rt->rt_gateway)) {
ND6_RUNLOCK();
SCTPDBG(SCTP_DEBUG_OUTPUT2, "pfxrouter is installed\n");
+ ND6_RUNLOCK();
return (1);
}
}
+ ND6_RUNLOCK();
SCTPDBG(SCTP_DEBUG_OUTPUT2, "pfxrouter is not installed\n");
return (0);
}
Modified: stable/11/sys/netinet6/in6.c
==============================================================================
--- stable/11/sys/netinet6/in6.c Tue Apr 11 17:36:19 2017 (r316713)
+++ stable/11/sys/netinet6/in6.c Tue Apr 11 18:48:17 2017 (r316714)
@@ -647,6 +647,7 @@ in6_control(struct socket *so, u_long cm
}
}
}
+ nd6_prefix_rele(pr);
/*
* this might affect the status of autoconfigured addresses,
@@ -694,8 +695,12 @@ aifaddr_out:
*/
pr = ia->ia6_ndpr;
in6_purgeaddr(&ia->ia_ifa);
- if (pr && pr->ndpr_addrcnt == 0)
- prelist_remove(pr);
+ if (pr != NULL && pr->ndpr_addrcnt == 0) {
+ ND6_WLOCK();
+ nd6_prefix_unlink(pr, NULL);
+ ND6_WUNLOCK();
+ nd6_prefix_del(pr);
+ }
EVENTHANDLER_INVOKE(ifaddr_event, ifp);
break;
}
Modified: stable/11/sys/netinet6/in6_ifattach.c
==============================================================================
--- stable/11/sys/netinet6/in6_ifattach.c Tue Apr 11 17:36:19 2017 (r316713)
+++ stable/11/sys/netinet6/in6_ifattach.c Tue Apr 11 18:48:17 2017 (r316714)
@@ -453,6 +453,7 @@ in6_ifattach_linklocal(struct ifnet *ifp
struct in6_ifaddr *ia;
struct in6_aliasreq ifra;
struct nd_prefixctl pr0;
+ struct nd_prefix *pr;
int error;
/*
@@ -535,10 +536,11 @@ in6_ifattach_linklocal(struct ifnet *ifp
* address, and then reconfigure another one, the prefix is still
* valid with referring to the old link-local address.
*/
- if (nd6_prefix_lookup(&pr0) == NULL) {
+ if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0)
return (error);
- }
+ } else
+ nd6_prefix_rele(pr);
return 0;
}
@@ -778,15 +780,6 @@ _in6_ifdetach(struct ifnet *ifp, int pur
return;
/*
- * Remove neighbor management table.
- * Enabling the nd6_purge will panic on vmove for interfaces on VNET
- * teardown as the IPv6 layer is cleaned up already and the locks
- * are destroyed.
- */
- if (purgeulp)
- nd6_purge(ifp);
-
- /*
* nuke any of IPv6 addresses we have
* XXX: all addresses should be already removed
*/
@@ -804,12 +797,10 @@ _in6_ifdetach(struct ifnet *ifp, int pur
in6_purgemaddrs(ifp);
/*
- * remove neighbor management table. we call it twice just to make
- * sure we nuke everything. maybe we need just one call.
- * XXX: since the first call did not release addresses, some prefixes
- * might remain. We should call nd6_purge() again to release the
- * prefixes after removing all addresses above.
- * (Or can we just delay calling nd6_purge until at this point?)
+ * Remove neighbor management table.
+ * Enabling the nd6_purge will panic on vmove for interfaces on VNET
+ * teardown as the IPv6 layer is cleaned up already and the locks
+ * are destroyed.
*/
if (purgeulp)
nd6_purge(ifp);
Modified: stable/11/sys/netinet6/nd6.c
==============================================================================
--- stable/11/sys/netinet6/nd6.c Tue Apr 11 17:36:19 2017 (r316713)
+++ stable/11/sys/netinet6/nd6.c Tue Apr 11 18:48:17 2017 (r316714)
@@ -38,8 +38,10 @@ __FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/callout.h>
+#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
+#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/time.h>
@@ -47,7 +49,6 @@ __FBSDID("$FreeBSD$");
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/syslog.h>
-#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/queue.h>
#include <sys/sdt.h>
@@ -118,6 +119,8 @@ static eventhandler_tag lle_event_eh, if
VNET_DEFINE(struct nd_drhead, nd_defrouter);
VNET_DEFINE(struct nd_prhead, nd_prefix);
VNET_DEFINE(struct rwlock, nd6_lock);
+VNET_DEFINE(uint64_t, nd6_list_genid);
+VNET_DEFINE(struct mtx, nd6_onlink_mtx);
VNET_DEFINE(int, nd6_recalc_reachtm_interval) = ND6_RECALC_REACHTM_INTERVAL;
#define V_nd6_recalc_reachtm_interval VNET(nd6_recalc_reachtm_interval)
@@ -209,11 +212,10 @@ void
nd6_init(void)
{
- rw_init(&V_nd6_lock, "nd6");
+ mtx_init(&V_nd6_onlink_mtx, "nd6 onlink", NULL, MTX_DEF);
+ rw_init(&V_nd6_lock, "nd6 list");
LIST_INIT(&V_nd_prefix);
-
- /* initialization of the default router list */
TAILQ_INIT(&V_nd_defrouter);
/* Start timers. */
@@ -245,6 +247,7 @@ nd6_destroy()
EVENTHANDLER_DEREGISTER(iflladdr_event, iflladdr_event_eh);
}
rw_destroy(&V_nd6_lock);
+ mtx_destroy(&V_nd6_onlink_mtx);
}
#endif
@@ -903,13 +906,15 @@ nd6_timer(void *arg)
{
CURVNET_SET((struct vnet *) arg);
struct nd_drhead drq;
+ struct nd_prhead prl;
struct nd_defrouter *dr, *ndr;
struct nd_prefix *pr, *npr;
struct in6_ifaddr *ia6, *nia6;
+ uint64_t genid;
TAILQ_INIT(&drq);
+ LIST_INIT(&prl);
- /* expire default router list */
ND6_WLOCK();
TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr)
if (dr->expire && dr->expire < time_uptime)
@@ -1016,22 +1021,46 @@ nd6_timer(void *arg)
}
}
- /* expire prefix list */
+ ND6_WLOCK();
+restart:
LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
/*
- * check prefix lifetime.
- * since pltime is just for autoconf, pltime processing for
- * prefix is not necessary.
+ * Expire prefixes. Since the pltime is only used for
+ * autoconfigured addresses, pltime processing for prefixes is
+ * not necessary.
+ *
+ * Only unlink after all derived addresses have expired. This
+ * may not occur until two hours after the prefix has expired
+ * per RFC 4862. If the prefix expires before its derived
+ * addresses, mark it off-link. This will be done automatically
+ * after unlinking if no address references remain.
*/
- if (pr->ndpr_vltime != ND6_INFINITE_LIFETIME &&
- time_uptime - pr->ndpr_lastupdate > pr->ndpr_vltime) {
+ if (pr->ndpr_vltime == ND6_INFINITE_LIFETIME ||
+ time_uptime - pr->ndpr_lastupdate <= pr->ndpr_vltime)
+ continue;
- /*
- * address expiration and prefix expiration are
- * separate. NEVER perform in6_purgeaddr here.
- */
- prelist_remove(pr);
+ if (pr->ndpr_addrcnt == 0) {
+ nd6_prefix_unlink(pr, &prl);
+ continue;
}
+ if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
+ genid = V_nd6_list_genid;
+ nd6_prefix_ref(pr);
+ ND6_WUNLOCK();
+ ND6_ONLINK_LOCK();
+ (void)nd6_prefix_offlink(pr);
+ ND6_ONLINK_UNLOCK();
+ ND6_WLOCK();
+ nd6_prefix_rele(pr);
+ if (genid != V_nd6_list_genid)
+ goto restart;
+ }
+ }
+ ND6_WUNLOCK();
+
+ while ((pr = LIST_FIRST(&prl)) != NULL) {
+ LIST_REMOVE(pr, ndpr_entry);
+ nd6_prefix_del(pr);
}
callout_reset(&V_nd6_timer_ch, V_nd6_prune * hz,
@@ -1118,10 +1147,12 @@ void
nd6_purge(struct ifnet *ifp)
{
struct nd_drhead drq;
+ struct nd_prhead prl;
struct nd_defrouter *dr, *ndr;
struct nd_prefix *pr, *npr;
TAILQ_INIT(&drq);
+ LIST_INIT(&prl);
/*
* Nuke default router list entries toward ifp.
@@ -1136,33 +1167,31 @@ nd6_purge(struct ifnet *ifp)
if (dr->ifp == ifp)
defrouter_unlink(dr, &drq);
}
-
TAILQ_FOREACH_SAFE(dr, &V_nd_defrouter, dr_entry, ndr) {
if (!dr->installed)
continue;
if (dr->ifp == ifp)
defrouter_unlink(dr, &drq);
}
+
+ /*
+ * Remove prefixes on ifp. We should have already removed addresses on
+ * this interface, so no addresses should be referencing these prefixes.
+ */
+ LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
+ if (pr->ndpr_ifp == ifp)
+ nd6_prefix_unlink(pr, &prl);
+ }
ND6_WUNLOCK();
+ /* Delete the unlinked router and prefix objects. */
while ((dr = TAILQ_FIRST(&drq)) != NULL) {
TAILQ_REMOVE(&drq, dr, dr_entry);
defrouter_del(dr);
}
-
- /* Nuke prefix list entries toward ifp */
- LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, npr) {
- if (pr->ndpr_ifp == ifp) {
- /*
- * Because if_detach() does *not* release prefixes
- * while purging addresses the reference count will
- * still be above zero. We therefore reset it to
- * make sure that the prefix really gets purged.
- */
- pr->ndpr_addrcnt = 0;
-
- prelist_remove(pr);
- }
+ while ((pr = LIST_FIRST(&prl)) != NULL) {
+ LIST_REMOVE(pr, ndpr_entry);
+ nd6_prefix_del(pr);
}
/* cancel default outgoing interface setting */
@@ -1228,7 +1257,8 @@ nd6_is_new_addr_neighbor(const struct so
struct rt_addrinfo info;
struct sockaddr_in6 rt_key;
const struct sockaddr *dst6;
- int fibnum;
+ uint64_t genid;
+ int error, fibnum;
/*
* A link-local address is always a neighbor.
@@ -1266,19 +1296,29 @@ nd6_is_new_addr_neighbor(const struct so
* If the address matches one of our on-link prefixes, it should be a
* neighbor.
*/
+ ND6_RLOCK();
+restart:
LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
if (pr->ndpr_ifp != ifp)
continue;
- if (!(pr->ndpr_stateflags & NDPRF_ONLINK)) {
-
+ if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
/* Always use the default FIB here. */
dst6 = (const struct sockaddr *)&pr->ndpr_prefix;
+ genid = V_nd6_list_genid;
+ ND6_RUNLOCK();
+
/* Restore length field before retrying lookup */
rt_key.sin6_len = sizeof(rt_key);
- if (rib_lookup_info(fibnum, dst6, 0, 0, &info) != 0)
+ error = rib_lookup_info(fibnum, dst6, 0, 0, &info);
+
+ ND6_RLOCK();
+ if (genid != V_nd6_list_genid)
+ goto restart;
+ if (error != 0)
continue;
+
/*
* This is the case where multiple interfaces
* have the same prefix, but only one is installed
@@ -1290,14 +1330,17 @@ nd6_is_new_addr_neighbor(const struct so
* differ.
*/
if (!IN6_ARE_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
- &rt_key.sin6_addr))
+ &rt_key.sin6_addr))
continue;
}
if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
- &addr->sin6_addr, &pr->ndpr_mask))
+ &addr->sin6_addr, &pr->ndpr_mask)) {
+ ND6_RUNLOCK();
return (1);
+ }
}
+ ND6_RUNLOCK();
/*
* If the address is assigned on the node of the other side of
@@ -1728,15 +1771,22 @@ nd6_ioctl(u_long cmd, caddr_t data, stru
case SIOCSPFXFLUSH_IN6:
{
/* flush all the prefix advertised by routers */
+ struct in6_ifaddr *ia, *ia_next;
struct nd_prefix *pr, *next;
+ struct nd_prhead prl;
- LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) {
- struct in6_ifaddr *ia, *ia_next;
+ LIST_INIT(&prl);
+ ND6_WLOCK();
+ LIST_FOREACH_SAFE(pr, &V_nd_prefix, ndpr_entry, next) {
if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
continue; /* XXX */
+ nd6_prefix_unlink(pr, &prl);
+ }
+ ND6_WUNLOCK();
- /* do we really have to remove addresses as well? */
+ while ((pr = LIST_FIRST(&prl)) != NULL) {
+ LIST_REMOVE(pr, ndpr_entry);
/* XXXRW: in6_ifaddrhead locking. */
TAILQ_FOREACH_SAFE(ia, &V_in6_ifaddrhead, ia_link,
ia_next) {
@@ -1746,7 +1796,7 @@ nd6_ioctl(u_long cmd, caddr_t data, stru
if (ia->ia6_ndpr == pr)
in6_purgeaddr(&ia->ia_ifa);
}
- prelist_remove(pr);
+ nd6_prefix_del(pr);
}
break;
}
@@ -2690,9 +2740,10 @@ nd6_sysctl_prlist(SYSCTL_HANDLER_ARGS)
ip6_sprintf(ip6buf, &pfr->router->rtaddr));
error = SYSCTL_OUT(req, &s6, sizeof(s6));
if (error != 0)
- break;
+ goto out;
}
}
+out:
ND6_RUNLOCK();
return (error);
}
Modified: stable/11/sys/netinet6/nd6.h
==============================================================================
--- stable/11/sys/netinet6/nd6.h Tue Apr 11 17:36:19 2017 (r316713)
+++ stable/11/sys/netinet6/nd6.h Tue Apr 11 18:48:17 2017 (r316714)
@@ -256,7 +256,7 @@ struct nd_prefixctl {
struct prf_ra ndpr_flags;
};
-
+LIST_HEAD(nd_prhead, nd_prefix);
struct nd_prefix {
struct ifnet *ndpr_ifp;
LIST_ENTRY(nd_prefix) ndpr_entry;
@@ -276,6 +276,7 @@ struct nd_prefix {
LIST_HEAD(pr_rtrhead, nd_pfxrouter) ndpr_advrtrs;
u_char ndpr_plen;
int ndpr_addrcnt; /* count of derived addresses */
+ volatile u_int ndpr_refcnt;
};
#define ndpr_raf ndpr_flags
@@ -314,8 +315,6 @@ struct nd_pfxrouter {
struct nd_defrouter *router;
};
-LIST_HEAD(nd_prhead, nd_prefix);
-
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_IP6NDP);
#endif
@@ -346,17 +345,30 @@ VNET_DECLARE(int, nd6_onlink_ns_rfc4861)
/* Lock for the prefix and default router lists. */
VNET_DECLARE(struct rwlock, nd6_lock);
+VNET_DECLARE(uint64_t, nd6_list_genid);
#define V_nd6_lock VNET(nd6_lock)
+#define V_nd6_list_genid VNET(nd6_list_genid)
#define ND6_RLOCK() rw_rlock(&V_nd6_lock)
#define ND6_RUNLOCK() rw_runlock(&V_nd6_lock)
#define ND6_WLOCK() rw_wlock(&V_nd6_lock)
#define ND6_WUNLOCK() rw_wunlock(&V_nd6_lock)
+#define ND6_TRY_UPGRADE() rw_try_upgrade(&V_nd6_lock)
#define ND6_WLOCK_ASSERT() rw_assert(&V_nd6_lock, RA_WLOCKED)
#define ND6_RLOCK_ASSERT() rw_assert(&V_nd6_lock, RA_RLOCKED)
#define ND6_LOCK_ASSERT() rw_assert(&V_nd6_lock, RA_LOCKED)
#define ND6_UNLOCK_ASSERT() rw_assert(&V_nd6_lock, RA_UNLOCKED)
+/* Mutex for prefix onlink/offlink transitions. */
+VNET_DECLARE(struct mtx, nd6_onlink_mtx);
+#define V_nd6_onlink_mtx VNET(nd6_onlink_mtx)
+
+#define ND6_ONLINK_LOCK() mtx_lock(&V_nd6_onlink_mtx)
+#define ND6_ONLINK_TRYLOCK() mtx_trylock(&V_nd6_onlink_mtx)
+#define ND6_ONLINK_UNLOCK() mtx_unlock(&V_nd6_onlink_mtx)
+#define ND6_ONLINK_LOCK_ASSERT() mtx_assert(&V_nd6_onlink_mtx, MA_OWNED)
+#define ND6_ONLINK_UNLOCK_ASSERT() mtx_assert(&V_nd6_onlink_mtx, MA_NOTOWNED)
+
#define nd6log(x) do { if (V_nd6_debug) log x; } while (/*CONSTCOND*/ 0)
/* nd6_rtr.c */
@@ -463,9 +475,14 @@ void defrouter_rele(struct nd_defrouter
bool defrouter_remove(struct in6_addr *, struct ifnet *);
void defrouter_unlink(struct nd_defrouter *, struct nd_drhead *);
void defrouter_del(struct nd_defrouter *);
-void prelist_remove(struct nd_prefix *);
int nd6_prelist_add(struct nd_prefixctl *, struct nd_defrouter *,
- struct nd_prefix **);
+ struct nd_prefix **);
+void nd6_prefix_unlink(struct nd_prefix *, struct nd_prhead *);
+void nd6_prefix_del(struct nd_prefix *);
+void nd6_prefix_ref(struct nd_prefix *);
+void nd6_prefix_rele(struct nd_prefix *);
+int nd6_prefix_onlink(struct nd_prefix *);
+int nd6_prefix_offlink(struct nd_prefix *);
void pfxlist_onlink_check(void);
struct nd_defrouter *defrouter_lookup(struct in6_addr *, struct ifnet *);
struct nd_defrouter *defrouter_lookup_locked(struct in6_addr *, struct ifnet *);
Modified: stable/11/sys/netinet6/nd6_rtr.c
==============================================================================
--- stable/11/sys/netinet6/nd6_rtr.c Tue Apr 11 17:36:19 2017 (r316713)
+++ stable/11/sys/netinet6/nd6_rtr.c Tue Apr 11 18:48:17 2017 (r316714)
@@ -87,9 +87,6 @@ static int in6_init_prefix_ltimes(struct
static void in6_init_address_ltimes(struct nd_prefix *,
struct in6_addrlifetime *);
-static int nd6_prefix_onlink(struct nd_prefix *);
-static int nd6_prefix_offlink(struct nd_prefix *);
-
static int rt6_deleteroute(const struct rtentry *, void *);
VNET_DECLARE(int, nd6_recalc_reachtm_interval);
@@ -661,6 +658,7 @@ defrouter_unlink(struct nd_defrouter *dr
ND6_WLOCK_ASSERT();
TAILQ_REMOVE(&V_nd_defrouter, dr, dr_entry);
+ V_nd6_list_genid++;
if (drq != NULL)
TAILQ_INSERT_TAIL(drq, dr, dr_entry);
}
@@ -670,6 +668,7 @@ defrouter_del(struct nd_defrouter *dr)
{
struct nd_defrouter *deldr = NULL;
struct nd_prefix *pr;
+ struct nd_pfxrouter *pfxrtr;
ND6_UNLOCK_ASSERT();
@@ -688,11 +687,13 @@ defrouter_del(struct nd_defrouter *dr)
/*
* Also delete all the pointers to the router in each prefix lists.
*/
+ ND6_WLOCK();
LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
- struct nd_pfxrouter *pfxrtr;
if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL)
pfxrtr_del(pfxrtr);
}
+ ND6_WUNLOCK();
+
pfxlist_onlink_check();
/*
@@ -852,14 +853,18 @@ static struct nd_defrouter *
defrtrlist_update(struct nd_defrouter *new)
{
struct nd_defrouter *dr, *n;
+ uint64_t genid;
int oldpref;
+ bool writelocked;
if (new->rtlifetime == 0) {
defrouter_remove(&new->rtaddr, new->ifp);
return (NULL);
}
- ND6_WLOCK();
+ ND6_RLOCK();
+ writelocked = false;
+restart:
dr = defrouter_lookup_locked(&new->rtaddr, new->ifp);
if (dr != NULL) {
oldpref = rtpref(dr);
@@ -875,10 +880,32 @@ defrtrlist_update(struct nd_defrouter *n
* router is still installed in the kernel.
*/
if (dr->installed && rtpref(new) == oldpref) {
- ND6_WUNLOCK();
+ if (writelocked)
+ ND6_WUNLOCK();
+ else
+ ND6_RUNLOCK();
return (dr);
}
+ }
+ /*
+ * The router needs to be reinserted into the default router
+ * list, so upgrade to a write lock. If that fails and the list
+ * has potentially changed while the lock was dropped, we'll
+ * redo the lookup with the write lock held.
+ */
+ if (!writelocked) {
+ writelocked = true;
+ if (!ND6_TRY_UPGRADE()) {
+ genid = V_nd6_list_genid;
+ ND6_RUNLOCK();
+ ND6_WLOCK();
+ if (genid != V_nd6_list_genid)
+ goto restart;
+ }
+ }
+
+ if (dr != NULL) {
/*
* The preferred router may have changed, so relocate this
* router.
@@ -912,6 +939,7 @@ defrtrlist_update(struct nd_defrouter *n
TAILQ_INSERT_BEFORE(dr, n, dr_entry);
else
TAILQ_INSERT_TAIL(&V_nd_defrouter, n, dr_entry);
+ V_nd6_list_genid++;
ND6_WUNLOCK();
defrouter_select();
@@ -924,11 +952,12 @@ pfxrtr_lookup(struct nd_prefix *pr, stru
{
struct nd_pfxrouter *search;
+ ND6_LOCK_ASSERT();
+
LIST_FOREACH(search, &pr->ndpr_advrtrs, pfr_entry) {
if (search->router == dr)
break;
}
-
return (search);
}
@@ -936,55 +965,110 @@ static void
pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr)
{
struct nd_pfxrouter *new;
+ bool update;
+
+ ND6_UNLOCK_ASSERT();
+
+ ND6_RLOCK();
+ if (pfxrtr_lookup(pr, dr) != NULL) {
+ ND6_RUNLOCK();
+ return;
+ }
+ ND6_RUNLOCK();
new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO);
if (new == NULL)
return;
- new->router = dr;
defrouter_ref(dr);
+ new->router = dr;
- LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry);
+ ND6_WLOCK();
+ if (pfxrtr_lookup(pr, dr) == NULL) {
+ LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry);
+ update = true;
+ } else {
+ /* We lost a race to add the reference. */
+ defrouter_rele(dr);
+ free(new, M_IP6NDP);
+ update = false;
+ }
+ ND6_WUNLOCK();
- pfxlist_onlink_check();
+ if (update)
+ pfxlist_onlink_check();
}
static void
pfxrtr_del(struct nd_pfxrouter *pfr)
{
+ ND6_WLOCK_ASSERT();
+
LIST_REMOVE(pfr, pfr_entry);
defrouter_rele(pfr->router);
free(pfr, M_IP6NDP);
}
-struct nd_prefix *
-nd6_prefix_lookup(struct nd_prefixctl *key)
+static struct nd_prefix *
+nd6_prefix_lookup_locked(struct nd_prefixctl *key)
{
struct nd_prefix *search;
+ ND6_LOCK_ASSERT();
+
LIST_FOREACH(search, &V_nd_prefix, ndpr_entry) {
if (key->ndpr_ifp == search->ndpr_ifp &&
key->ndpr_plen == search->ndpr_plen &&
in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr,
&search->ndpr_prefix.sin6_addr, key->ndpr_plen)) {
+ nd6_prefix_ref(search);
break;
}
}
+ return (search);
+}
+struct nd_prefix *
+nd6_prefix_lookup(struct nd_prefixctl *key)
+{
+ struct nd_prefix *search;
+
+ ND6_RLOCK();
+ search = nd6_prefix_lookup_locked(key);
+ ND6_RUNLOCK();
return (search);
}
+void
+nd6_prefix_ref(struct nd_prefix *pr)
+{
+
+ refcount_acquire(&pr->ndpr_refcnt);
+}
+
+void
+nd6_prefix_rele(struct nd_prefix *pr)
+{
+
+ if (refcount_release(&pr->ndpr_refcnt)) {
+ KASSERT(LIST_EMPTY(&pr->ndpr_advrtrs),
+ ("prefix %p has advertising routers", pr));
+ free(pr, M_IP6NDP);
+ }
+}
+
int
nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr,
struct nd_prefix **newp)
{
- struct nd_prefix *new = NULL;
- int error = 0;
+ struct nd_prefix *new;
char ip6buf[INET6_ADDRSTRLEN];
+ int error;
new = malloc(sizeof(*new), M_IP6NDP, M_NOWAIT | M_ZERO);
if (new == NULL)
return (ENOMEM);
+ refcount_init(&new->ndpr_refcnt, newp != NULL ? 2 : 1);
new->ndpr_ifp = pr->ndpr_ifp;
new->ndpr_prefix = pr->ndpr_prefix;
new->ndpr_plen = pr->ndpr_plen;
@@ -1003,20 +1087,22 @@ nd6_prelist_add(struct nd_prefixctl *pr,
/* make prefix in the canonical form */
IN6_MASK_ADDR(&new->ndpr_prefix.sin6_addr, &new->ndpr_mask);
- /* link ndpr_entry to nd_prefix list */
+ ND6_WLOCK();
LIST_INSERT_HEAD(&V_nd_prefix, new, ndpr_entry);
+ V_nd6_list_genid++;
+ ND6_WUNLOCK();
/* ND_OPT_PI_FLAG_ONLINK processing */
if (new->ndpr_raf_onlink) {
- int e;
-
- if ((e = nd6_prefix_onlink(new)) != 0) {
+ ND6_ONLINK_LOCK();
+ if ((error = nd6_prefix_onlink(new)) != 0) {
nd6log((LOG_ERR, "nd6_prelist_add: failed to make "
"the prefix %s/%d on-link on %s (errno=%d)\n",
ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
- pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
+ pr->ndpr_plen, if_name(pr->ndpr_ifp), error));
/* proceed anyway. XXX: is it correct? */
}
+ ND6_ONLINK_UNLOCK();
}
if (dr != NULL)
@@ -1026,51 +1112,67 @@ nd6_prelist_add(struct nd_prefixctl *pr,
return (0);
}
+/*
+ * Remove a prefix from the prefix list and optionally stash it in a
+ * caller-provided list.
+ *
+ * The ND6 lock must be held.
+ */
void
-prelist_remove(struct nd_prefix *pr)
+nd6_prefix_unlink(struct nd_prefix *pr, struct nd_prhead *list)
+{
+
+ ND6_WLOCK_ASSERT();
+
+ LIST_REMOVE(pr, ndpr_entry);
+ V_nd6_list_genid++;
+ if (list != NULL)
+ LIST_INSERT_HEAD(list, pr, ndpr_entry);
+}
+
+/*
+ * Free an unlinked prefix, first marking it off-link if necessary.
+ */
+void
+nd6_prefix_del(struct nd_prefix *pr)
{
struct nd_pfxrouter *pfr, *next;
int e;
char ip6buf[INET6_ADDRSTRLEN];
- /* make sure to invalidate the prefix until it is really freed. */
- pr->ndpr_vltime = 0;
- pr->ndpr_pltime = 0;
+ KASSERT(pr->ndpr_addrcnt == 0,
+ ("prefix %p has referencing addresses", pr));
+ ND6_UNLOCK_ASSERT();
/*
* Though these flags are now meaningless, we'd rather keep the value
* of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users
* when executing "ndp -p".
*/
-
- if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 &&
- (e = nd6_prefix_offlink(pr)) != 0) {
- nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink "
- "on %s, errno=%d\n",
- ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
- pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
- /* what should we do? */
+ if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
+ ND6_ONLINK_LOCK();
+ if ((e = nd6_prefix_offlink(pr)) != 0) {
+ nd6log((LOG_ERR,
+ "nd6_prefix_del: failed to make %s/%d offlink "
+ "on %s, errno=%d\n",
+ ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
+ pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
+ /* what should we do? */
+ }
+ ND6_ONLINK_UNLOCK();
}
- if (pr->ndpr_addrcnt > 0)
- return; /* notice here? */
-
- /* unlink ndpr_entry from nd_prefix list */
- LIST_REMOVE(pr, ndpr_entry);
-
- /* free list of routers that advertised the prefix */
- LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next) {
+ /* Release references to routers that have advertised this prefix. */
+ ND6_WLOCK();
+ LIST_FOREACH_SAFE(pfr, &pr->ndpr_advrtrs, pfr_entry, next)
pfxrtr_del(pfr);
- }
- free(pr, M_IP6NDP);
+ ND6_WUNLOCK();
+
+ nd6_prefix_rele(pr);
pfxlist_onlink_check();
}
-/*
- * dr - may be NULL
- */
-
static int
prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr,
struct mbuf *m, int mcast)
@@ -1120,21 +1222,22 @@ prelist_update(struct nd_prefixctl *new,
if (new->ndpr_raf_onlink &&
(pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
- int e;
-
- if ((e = nd6_prefix_onlink(pr)) != 0) {
+ ND6_ONLINK_LOCK();
+ if ((error = nd6_prefix_onlink(pr)) != 0) {
nd6log((LOG_ERR,
"prelist_update: failed to make "
"the prefix %s/%d on-link on %s "
"(errno=%d)\n",
ip6_sprintf(ip6buf,
- &pr->ndpr_prefix.sin6_addr),
- pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
+ &pr->ndpr_prefix.sin6_addr),
+ pr->ndpr_plen, if_name(pr->ndpr_ifp),
+ error));
/* proceed anyway. XXX: is it correct? */
}
+ ND6_ONLINK_UNLOCK();
}
- if (dr && pfxrtr_lookup(pr, dr) == NULL)
+ if (dr != NULL)
pfxrtr_add(pr, dr);
} else {
if (new->ndpr_vltime == 0)
@@ -1393,8 +1496,10 @@ prelist_update(struct nd_prefixctl *new,
}
}
- end:
- return error;
+end:
+ if (pr != NULL)
+ nd6_prefix_rele(pr);
+ return (error);
}
/*
@@ -1409,6 +1514,8 @@ find_pfxlist_reachable_router(struct nd_
struct llentry *ln;
int canreach;
+ ND6_LOCK_ASSERT();
+
LIST_FOREACH(pfxrtr, &pr->ndpr_advrtrs, pfr_entry) {
IF_AFDATA_RLOCK(pfxrtr->router->ifp);
ln = nd6_lookup(&pfxrtr->router->rtaddr, 0, pfxrtr->router->ifp);
@@ -1444,6 +1551,11 @@ pfxlist_onlink_check(void)
struct nd_defrouter *dr;
struct nd_pfxrouter *pfxrtr = NULL;
struct rm_priotracker in6_ifa_tracker;
+ uint64_t genid;
+ uint32_t flags;
+
+ ND6_ONLINK_LOCK();
+ ND6_RLOCK();
/*
* Check if there is a prefix that has a reachable advertising
@@ -1459,7 +1571,6 @@ pfxlist_onlink_check(void)
* that does not advertise any prefixes.
*/
if (pr == NULL) {
- ND6_RLOCK();
TAILQ_FOREACH(dr, &V_nd_defrouter, dr_entry) {
struct nd_prefix *pr0;
@@ -1470,7 +1581,6 @@ pfxlist_onlink_check(void)
if (pfxrtr != NULL)
break;
}
- ND6_RUNLOCK();
}
if (pr != NULL || (!TAILQ_EMPTY(&V_nd_defrouter) && pfxrtr == NULL)) {
/*
@@ -1515,6 +1625,7 @@ pfxlist_onlink_check(void)
* interfaces. Such cases will be handled in nd6_prefix_onlink,
* so we don't have to care about them.
*/
+restart:
LIST_FOREACH(pr, &V_nd_prefix, ndpr_entry) {
char ip6buf[INET6_ADDRSTRLEN];
int e;
@@ -1524,21 +1635,20 @@ pfxlist_onlink_check(void)
pr->ndpr_raf_auto == 0)
continue;
- if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 &&
- (pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
- if ((e = nd6_prefix_offlink(pr)) != 0) {
+ flags = pr->ndpr_stateflags & (NDPRF_DETACHED | NDPRF_ONLINK);
+ if (flags == 0 || flags == (NDPRF_DETACHED | NDPRF_ONLINK)) {
+ genid = V_nd6_list_genid;
+ ND6_RUNLOCK();
+ if ((flags & NDPRF_ONLINK) != 0 &&
+ (e = nd6_prefix_offlink(pr)) != 0) {
nd6log((LOG_ERR,
"pfxlist_onlink_check: failed to "
"make %s/%d offlink, errno=%d\n",
ip6_sprintf(ip6buf,
&pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, e));
- }
- }
- if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 &&
- (pr->ndpr_stateflags & NDPRF_ONLINK) == 0 &&
- pr->ndpr_raf_onlink) {
- if ((e = nd6_prefix_onlink(pr)) != 0) {
+ } else if ((flags & NDPRF_ONLINK) == 0 &&
+ (e = nd6_prefix_onlink(pr)) != 0) {
nd6log((LOG_ERR,
"pfxlist_onlink_check: failed to "
"make %s/%d onlink, errno=%d\n",
@@ -1546,6 +1656,9 @@ pfxlist_onlink_check(void)
&pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, e));
}
+ ND6_RLOCK();
+ if (genid != V_nd6_list_genid)
+ goto restart;
}
}
@@ -1606,6 +1719,8 @@ pfxlist_onlink_check(void)
}
}
IN6_IFADDR_RUNLOCK(&in6_ifa_tracker);
+ ND6_RUNLOCK();
+ ND6_ONLINK_UNLOCK();
}
static int
@@ -1686,23 +1801,20 @@ nd6_prefix_onlink_rtrequest(struct nd_pr
return (a_failure);
}
-static int
+int
nd6_prefix_onlink(struct nd_prefix *pr)
{
struct ifaddr *ifa;
struct ifnet *ifp = pr->ndpr_ifp;
struct nd_prefix *opr;
- int error = 0;
char ip6buf[INET6_ADDRSTRLEN];
+ int error;
- /* sanity check */
- if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
- nd6log((LOG_ERR,
- "nd6_prefix_onlink: %s/%d is already on-link\n",
- ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
*** DIFF OUTPUT TRUNCATED AT 1000 LINES ***
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