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Improve locking of multicast addresses in VLAN and LAGG interfaces.

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This fixes several scenarios of reproducible panics, cause by races
between multicast address changes and interface destruction.

MFC after:	2 weeks
This commit is contained in:
Alexander Motin 2014-08-04 00:58:12 +00:00
parent 6dde7ecb5d
commit 2d222cb761
3 changed files with 38 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
sys/net/if_lagg.c
View File

@ -1217,35 +1217,39 @@ lagg_ether_cmdmulti(struct lagg_port *lp, int set)
struct ifnet *ifp = lp->lp_ifp;
struct ifnet *scifp = sc->sc_ifp;
struct lagg_mc *mc;
struct ifmultiaddr *ifma, *rifma = NULL;
struct sockaddr_dl sdl;
struct ifmultiaddr *ifma;
int error;
LAGG_WLOCK_ASSERT(sc);
link_init_sdl(ifp, (struct sockaddr *)&sdl, IFT_ETHER);
sdl.sdl_alen = ETHER_ADDR_LEN;
if (set) {
IF_ADDR_WLOCK(scifp);
TAILQ_FOREACH(ifma, &scifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_LINK)
continue;
bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
LLADDR(&sdl), ETHER_ADDR_LEN);
error = if_addmulti(ifp, (struct sockaddr *)&sdl, &rifma);
mc = malloc(sizeof(struct lagg_mc), M_DEVBUF, M_NOWAIT);
if (mc == NULL) {
IF_ADDR_WUNLOCK(scifp);
return (ENOMEM);
}
bcopy(ifma->ifma_addr, &mc->mc_addr,
ifma->ifma_addr->sa_len);
mc->mc_addr.sdl_index = ifp->if_index;
mc->mc_ifma = NULL;
SLIST_INSERT_HEAD(&lp->lp_mc_head, mc, mc_entries);
}
IF_ADDR_WUNLOCK(scifp);
SLIST_FOREACH (mc, &lp->lp_mc_head, mc_entries) {
error = if_addmulti(ifp,
(struct sockaddr *)&mc->mc_addr, &mc->mc_ifma);
if (error)
return (error);
mc = malloc(sizeof(struct lagg_mc), M_DEVBUF, M_NOWAIT);
if (mc == NULL)
return (ENOMEM);
mc->mc_ifma = rifma;
SLIST_INSERT_HEAD(&lp->lp_mc_head, mc, mc_entries);
}
} else {
while ((mc = SLIST_FIRST(&lp->lp_mc_head)) != NULL) {
SLIST_REMOVE(&lp->lp_mc_head, mc, lagg_mc, mc_entries);
if_delmulti_ifma(mc->mc_ifma);
if (mc->mc_ifma && !lp->lp_detaching)
if_delmulti_ifma(mc->mc_ifma);
free(mc, M_DEVBUF);
}
}

1
sys/net/if_lagg.h
View File

@ -174,6 +174,7 @@ struct lagg_lb {
};
struct lagg_mc {
struct sockaddr_dl mc_addr;
struct ifmultiaddr *mc_ifma;
SLIST_ENTRY(lagg_mc) mc_entries;
};

31
sys/net/if_vlan.c
View File

@ -460,48 +460,48 @@ trunk_destroy(struct ifvlantrunk *trunk)
* traffic that it doesn't really want, which ends up being discarded
* later by the upper protocol layers. Unfortunately, there's no way
* to avoid this: there really is only one physical interface.
*
* XXX: There is a possible race here if more than one thread is
* modifying the multicast state of the vlan interface at the same time.
*/
static int
vlan_setmulti(struct ifnet *ifp)
{
struct ifnet *ifp_p;
struct ifmultiaddr *ifma, *rifma = NULL;
struct ifmultiaddr *ifma;
struct ifvlan *sc;
struct vlan_mc_entry *mc;
int error;
/*VLAN_LOCK_ASSERT();*/
/* Find the parent. */
sc = ifp->if_softc;
TRUNK_LOCK_ASSERT(TRUNK(sc));
ifp_p = PARENT(sc);
CURVNET_SET_QUIET(ifp_p->if_vnet);
/* First, remove any existing filter entries. */
while ((mc = SLIST_FIRST(&sc->vlan_mc_listhead)) != NULL) {
error = if_delmulti(ifp_p, (struct sockaddr *)&mc->mc_addr);
if (error)
return (error);
SLIST_REMOVE_HEAD(&sc->vlan_mc_listhead, mc_entries);
(void)if_delmulti(ifp_p, (struct sockaddr *)&mc->mc_addr);
free(mc, M_VLAN);
}
/* Now program new ones. */
IF_ADDR_WLOCK(ifp);
TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
if (ifma->ifma_addr->sa_family != AF_LINK)
continue;
mc = malloc(sizeof(struct vlan_mc_entry), M_VLAN, M_NOWAIT);
if (mc == NULL)
if (mc == NULL) {
IF_ADDR_WUNLOCK(ifp);
return (ENOMEM);
}
bcopy(ifma->ifma_addr, &mc->mc_addr, ifma->ifma_addr->sa_len);
mc->mc_addr.sdl_index = ifp_p->if_index;
SLIST_INSERT_HEAD(&sc->vlan_mc_listhead, mc, mc_entries);
}
IF_ADDR_WUNLOCK(ifp);
SLIST_FOREACH (mc, &sc->vlan_mc_listhead, mc_entries) {
error = if_addmulti(ifp_p, (struct sockaddr *)&mc->mc_addr,
&rifma);
NULL);
if (error)
return (error);
}
@ -1374,7 +1374,7 @@ vlan_unconfig_locked(struct ifnet *ifp, int departing)
* Check if we were the last.
*/
if (trunk->refcnt == 0) {
trunk->parent->if_vlantrunk = NULL;
parent->if_vlantrunk = NULL;
/*
* XXXGL: If some ithread has already entered
* vlan_input() and is now blocked on the trunk
@ -1568,6 +1568,7 @@ vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
struct ifreq *ifr;
struct ifaddr *ifa;
struct ifvlan *ifv;
struct ifvlantrunk *trunk;
struct vlanreq vlr;
int error = 0;
@ -1712,8 +1713,12 @@ vlan_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
* If we don't have a parent, just remember the membership for
* when we do.
*/
if (TRUNK(ifv) != NULL)
trunk = TRUNK(ifv);
if (trunk != NULL) {
TRUNK_LOCK(trunk);
error = vlan_setmulti(ifp);
TRUNK_UNLOCK(trunk);
}
break;
default: