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Diffstat (limited to 'net/ipv4/igmp.c')
-rw-r--r--net/ipv4/igmp.c151
1 files changed, 85 insertions, 66 deletions
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 3b9c7a2725a9..81be3e0f0e70 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -107,8 +107,6 @@
#ifdef CONFIG_IP_MULTICAST
/* Parameter names and values are taken from igmp-v2-06 draft */
-#define IGMP_V2_UNSOLICITED_REPORT_INTERVAL (10*HZ)
-#define IGMP_V3_UNSOLICITED_REPORT_INTERVAL (1*HZ)
#define IGMP_QUERY_INTERVAL (125*HZ)
#define IGMP_QUERY_RESPONSE_INTERVAL (10*HZ)
@@ -215,7 +213,7 @@ static void igmp_stop_timer(struct ip_mc_list *im)
/* It must be called with locked im->lock */
static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
{
- int tv = prandom_u32() % max_delay;
+ int tv = prandom_u32_max(max_delay);
im->tm_running = 1;
if (!mod_timer(&im->timer, jiffies+tv+2))
@@ -224,7 +222,7 @@ static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
static void igmp_gq_start_timer(struct in_device *in_dev)
{
- int tv = prandom_u32() % in_dev->mr_maxdelay;
+ int tv = prandom_u32_max(in_dev->mr_maxdelay);
unsigned long exp = jiffies + tv + 2;
if (in_dev->mr_gq_running &&
@@ -238,7 +236,7 @@ static void igmp_gq_start_timer(struct in_device *in_dev)
static void igmp_ifc_start_timer(struct in_device *in_dev, int delay)
{
- int tv = prandom_u32() % delay;
+ int tv = prandom_u32_max(delay);
if (!mod_timer(&in_dev->mr_ifc_timer, jiffies+tv+2))
in_dev_hold(in_dev);
@@ -469,7 +467,8 @@ static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
if (pmc->multiaddr == IGMP_ALL_HOSTS)
return skb;
- if (ipv4_is_local_multicast(pmc->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
+ if (ipv4_is_local_multicast(pmc->multiaddr) &&
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
return skb;
mtu = READ_ONCE(dev->mtu);
@@ -595,7 +594,7 @@ static int igmpv3_send_report(struct in_device *in_dev, struct ip_mc_list *pmc)
if (pmc->multiaddr == IGMP_ALL_HOSTS)
continue;
if (ipv4_is_local_multicast(pmc->multiaddr) &&
- !net->ipv4.sysctl_igmp_llm_reports)
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
continue;
spin_lock_bh(&pmc->lock);
if (pmc->sfcount[MCAST_EXCLUDE])
@@ -738,7 +737,8 @@ static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
if (type == IGMPV3_HOST_MEMBERSHIP_REPORT)
return igmpv3_send_report(in_dev, pmc);
- if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
+ if (ipv4_is_local_multicast(group) &&
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
return 0;
if (type == IGMP_HOST_LEAVE_MESSAGE)
@@ -805,10 +805,17 @@ static void igmp_gq_timer_expire(struct timer_list *t)
static void igmp_ifc_timer_expire(struct timer_list *t)
{
struct in_device *in_dev = from_timer(in_dev, t, mr_ifc_timer);
+ u32 mr_ifc_count;
igmpv3_send_cr(in_dev);
- if (in_dev->mr_ifc_count) {
- in_dev->mr_ifc_count--;
+restart:
+ mr_ifc_count = READ_ONCE(in_dev->mr_ifc_count);
+
+ if (mr_ifc_count) {
+ if (cmpxchg(&in_dev->mr_ifc_count,
+ mr_ifc_count,
+ mr_ifc_count - 1) != mr_ifc_count)
+ goto restart;
igmp_ifc_start_timer(in_dev,
unsolicited_report_interval(in_dev));
}
@@ -820,7 +827,7 @@ static void igmp_ifc_event(struct in_device *in_dev)
struct net *net = dev_net(in_dev->dev);
if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev))
return;
- in_dev->mr_ifc_count = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
+ WRITE_ONCE(in_dev->mr_ifc_count, in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv));
igmp_ifc_start_timer(in_dev, 1);
}
@@ -915,7 +922,8 @@ static bool igmp_heard_report(struct in_device *in_dev, __be32 group)
if (group == IGMP_ALL_HOSTS)
return false;
- if (ipv4_is_local_multicast(group) && !net->ipv4.sysctl_igmp_llm_reports)
+ if (ipv4_is_local_multicast(group) &&
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
return false;
rcu_read_lock();
@@ -959,7 +967,7 @@ static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
in_dev->mr_qri;
}
/* cancel the interface change timer */
- in_dev->mr_ifc_count = 0;
+ WRITE_ONCE(in_dev->mr_ifc_count, 0);
if (del_timer(&in_dev->mr_ifc_timer))
__in_dev_put(in_dev);
/* clear deleted report items */
@@ -1001,7 +1009,7 @@ static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
* received value was zero, use the default or statically
* configured value.
*/
- in_dev->mr_qrv = ih3->qrv ?: net->ipv4.sysctl_igmp_qrv;
+ in_dev->mr_qrv = ih3->qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
in_dev->mr_qi = IGMPV3_QQIC(ih3->qqic)*HZ ?: IGMP_QUERY_INTERVAL;
/* RFC3376, 8.3. Query Response Interval:
@@ -1040,7 +1048,7 @@ static bool igmp_heard_query(struct in_device *in_dev, struct sk_buff *skb,
if (im->multiaddr == IGMP_ALL_HOSTS)
continue;
if (ipv4_is_local_multicast(im->multiaddr) &&
- !net->ipv4.sysctl_igmp_llm_reports)
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
continue;
spin_lock_bh(&im->lock);
if (im->tm_running)
@@ -1181,7 +1189,7 @@ static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im,
pmc->interface = im->interface;
in_dev_hold(in_dev);
pmc->multiaddr = im->multiaddr;
- pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
+ pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
pmc->sfmode = im->sfmode;
if (pmc->sfmode == MCAST_INCLUDE) {
struct ip_sf_list *psf;
@@ -1232,9 +1240,11 @@ static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
swap(im->tomb, pmc->tomb);
swap(im->sources, pmc->sources);
for (psf = im->sources; psf; psf = psf->sf_next)
- psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
+ psf->sf_crcount = in_dev->mr_qrv ?:
+ READ_ONCE(net->ipv4.sysctl_igmp_qrv);
} else {
- im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
+ im->crcount = in_dev->mr_qrv ?:
+ READ_ONCE(net->ipv4.sysctl_igmp_qrv);
}
in_dev_put(pmc->interface);
kfree_pmc(pmc);
@@ -1291,7 +1301,8 @@ static void __igmp_group_dropped(struct ip_mc_list *im, gfp_t gfp)
#ifdef CONFIG_IP_MULTICAST
if (im->multiaddr == IGMP_ALL_HOSTS)
return;
- if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
+ if (ipv4_is_local_multicast(im->multiaddr) &&
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
return;
reporter = im->reporter;
@@ -1333,13 +1344,14 @@ static void igmp_group_added(struct ip_mc_list *im)
#ifdef CONFIG_IP_MULTICAST
if (im->multiaddr == IGMP_ALL_HOSTS)
return;
- if (ipv4_is_local_multicast(im->multiaddr) && !net->ipv4.sysctl_igmp_llm_reports)
+ if (ipv4_is_local_multicast(im->multiaddr) &&
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
return;
if (in_dev->dead)
return;
- im->unsolicit_count = net->ipv4.sysctl_igmp_qrv;
+ im->unsolicit_count = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
if (IGMP_V1_SEEN(in_dev) || IGMP_V2_SEEN(in_dev)) {
spin_lock_bh(&im->lock);
igmp_start_timer(im, IGMP_INITIAL_REPORT_DELAY);
@@ -1353,7 +1365,7 @@ static void igmp_group_added(struct ip_mc_list *im)
* IN() to IN(A).
*/
if (im->sfmode == MCAST_EXCLUDE)
- im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
+ im->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
igmp_ifc_event(in_dev);
#endif
@@ -1637,7 +1649,7 @@ static void ip_mc_rejoin_groups(struct in_device *in_dev)
if (im->multiaddr == IGMP_ALL_HOSTS)
continue;
if (ipv4_is_local_multicast(im->multiaddr) &&
- !net->ipv4.sysctl_igmp_llm_reports)
+ !READ_ONCE(net->ipv4.sysctl_igmp_llm_reports))
continue;
/* a failover is happening and switches
@@ -1726,7 +1738,7 @@ void ip_mc_down(struct in_device *in_dev)
igmp_group_dropped(pmc);
#ifdef CONFIG_IP_MULTICAST
- in_dev->mr_ifc_count = 0;
+ WRITE_ONCE(in_dev->mr_ifc_count, 0);
if (del_timer(&in_dev->mr_ifc_timer))
__in_dev_put(in_dev);
in_dev->mr_gq_running = 0;
@@ -1744,7 +1756,7 @@ static void ip_mc_reset(struct in_device *in_dev)
in_dev->mr_qi = IGMP_QUERY_INTERVAL;
in_dev->mr_qri = IGMP_QUERY_RESPONSE_INTERVAL;
- in_dev->mr_qrv = net->ipv4.sysctl_igmp_qrv;
+ in_dev->mr_qrv = READ_ONCE(net->ipv4.sysctl_igmp_qrv);
}
#else
static void ip_mc_reset(struct in_device *in_dev)
@@ -1803,6 +1815,7 @@ void ip_mc_destroy_dev(struct in_device *in_dev)
while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
in_dev->mc_list = i->next_rcu;
in_dev->mc_count--;
+ ip_mc_clear_src(i);
ip_ma_put(i);
}
}
@@ -1877,7 +1890,7 @@ static int ip_mc_del1_src(struct ip_mc_list *pmc, int sfmode,
#ifdef CONFIG_IP_MULTICAST
if (psf->sf_oldin &&
!IGMP_V1_SEEN(in_dev) && !IGMP_V2_SEEN(in_dev)) {
- psf->sf_crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
+ psf->sf_crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
psf->sf_next = pmc->tomb;
pmc->tomb = psf;
rv = 1;
@@ -1941,8 +1954,8 @@ static int ip_mc_del_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
/* filter mode change */
pmc->sfmode = MCAST_INCLUDE;
#ifdef CONFIG_IP_MULTICAST
- pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
- in_dev->mr_ifc_count = pmc->crcount;
+ pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
+ WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
for (psf = pmc->sources; psf; psf = psf->sf_next)
psf->sf_crcount = 0;
igmp_ifc_event(pmc->interface);
@@ -2120,8 +2133,8 @@ static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
#ifdef CONFIG_IP_MULTICAST
/* else no filters; keep old mode for reports */
- pmc->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
- in_dev->mr_ifc_count = pmc->crcount;
+ pmc->crcount = in_dev->mr_qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv);
+ WRITE_ONCE(in_dev->mr_ifc_count, pmc->crcount);
for (psf = pmc->sources; psf; psf = psf->sf_next)
psf->sf_crcount = 0;
igmp_ifc_event(in_dev);
@@ -2186,7 +2199,7 @@ static int __ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr,
count++;
}
err = -ENOBUFS;
- if (count >= net->ipv4.sysctl_igmp_max_memberships)
+ if (count >= READ_ONCE(net->ipv4.sysctl_igmp_max_memberships))
goto done;
iml = sock_kmalloc(sk, sizeof(*iml), GFP_KERNEL);
if (!iml)
@@ -2234,7 +2247,7 @@ static int ip_mc_leave_src(struct sock *sk, struct ip_mc_socklist *iml,
iml->sfmode, psf->sl_count, psf->sl_addr, 0);
RCU_INIT_POINTER(iml->sflist, NULL);
/* decrease mem now to avoid the memleak warning */
- atomic_sub(IP_SFLSIZE(psf->sl_max), &sk->sk_omem_alloc);
+ atomic_sub(struct_size(psf, sl_addr, psf->sl_max), &sk->sk_omem_alloc);
kfree_rcu(psf, rcu);
return err;
}
@@ -2373,7 +2386,7 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
}
/* else, add a new source to the filter */
- if (psl && psl->sl_count >= net->ipv4.sysctl_igmp_max_msf) {
+ if (psl && psl->sl_count >= READ_ONCE(net->ipv4.sysctl_igmp_max_msf)) {
err = -ENOBUFS;
goto done;
}
@@ -2383,7 +2396,8 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
if (psl)
count += psl->sl_max;
- newpsl = sock_kmalloc(sk, IP_SFLSIZE(count), GFP_KERNEL);
+ newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr, count),
+ GFP_KERNEL);
if (!newpsl) {
err = -ENOBUFS;
goto done;
@@ -2394,10 +2408,12 @@ int ip_mc_source(int add, int omode, struct sock *sk, struct
for (i = 0; i < psl->sl_count; i++)
newpsl->sl_addr[i] = psl->sl_addr[i];
/* decrease mem now to avoid the memleak warning */
- atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
- kfree_rcu(psl, rcu);
+ atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
+ &sk->sk_omem_alloc);
}
rcu_assign_pointer(pmc->sflist, newpsl);
+ if (psl)
+ kfree_rcu(psl, rcu);
psl = newpsl;
}
rv = 1; /* > 0 for insert logic below if sl_count is 0 */
@@ -2469,19 +2485,22 @@ int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
goto done;
}
if (msf->imsf_numsrc) {
- newpsl = sock_kmalloc(sk, IP_SFLSIZE(msf->imsf_numsrc),
- GFP_KERNEL);
+ newpsl = sock_kmalloc(sk, struct_size(newpsl, sl_addr,
+ msf->imsf_numsrc),
+ GFP_KERNEL);
if (!newpsl) {
err = -ENOBUFS;
goto done;
}
newpsl->sl_max = newpsl->sl_count = msf->imsf_numsrc;
- memcpy(newpsl->sl_addr, msf->imsf_slist,
- msf->imsf_numsrc * sizeof(msf->imsf_slist[0]));
+ memcpy(newpsl->sl_addr, msf->imsf_slist_flex,
+ flex_array_size(msf, imsf_slist_flex, msf->imsf_numsrc));
err = ip_mc_add_src(in_dev, &msf->imsf_multiaddr,
msf->imsf_fmode, newpsl->sl_count, newpsl->sl_addr, 0);
if (err) {
- sock_kfree_s(sk, newpsl, IP_SFLSIZE(newpsl->sl_max));
+ sock_kfree_s(sk, newpsl,
+ struct_size(newpsl, sl_addr,
+ newpsl->sl_max));
goto done;
}
} else {
@@ -2494,12 +2513,15 @@ int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf, int ifindex)
(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
psl->sl_count, psl->sl_addr, 0);
/* decrease mem now to avoid the memleak warning */
- atomic_sub(IP_SFLSIZE(psl->sl_max), &sk->sk_omem_alloc);
- kfree_rcu(psl, rcu);
- } else
+ atomic_sub(struct_size(psl, sl_addr, psl->sl_max),
+ &sk->sk_omem_alloc);
+ } else {
(void) ip_mc_del_src(in_dev, &msf->imsf_multiaddr, pmc->sfmode,
0, NULL, 0);
+ }
rcu_assign_pointer(pmc->sflist, newpsl);
+ if (psl)
+ kfree_rcu(psl, rcu);
pmc->sfmode = msf->imsf_fmode;
err = 0;
done:
@@ -2507,11 +2529,10 @@ done:
err = ip_mc_leave_group(sk, &imr);
return err;
}
-
int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
- struct ip_msfilter __user *optval, int __user *optlen)
+ sockptr_t optval, sockptr_t optlen)
{
- int err, len, count, copycount;
+ int err, len, count, copycount, msf_size;
struct ip_mreqn imr;
__be32 addr = msf->imsf_multiaddr;
struct ip_mc_socklist *pmc;
@@ -2546,20 +2567,22 @@ int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
msf->imsf_fmode = pmc->sfmode;
psl = rtnl_dereference(pmc->sflist);
if (!psl) {
- len = 0;
count = 0;
} else {
count = psl->sl_count;
}
copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
- len = copycount * sizeof(psl->sl_addr[0]);
+ len = flex_array_size(psl, sl_addr, copycount);
msf->imsf_numsrc = count;
- if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
- copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
+ msf_size = IP_MSFILTER_SIZE(copycount);
+ if (copy_to_sockptr(optlen, &msf_size, sizeof(int)) ||
+ copy_to_sockptr(optval, msf, IP_MSFILTER_SIZE(0))) {
return -EFAULT;
}
if (len &&
- copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
+ copy_to_sockptr_offset(optval,
+ offsetof(struct ip_msfilter, imsf_slist_flex),
+ psl->sl_addr, len))
return -EFAULT;
return 0;
done:
@@ -2567,9 +2590,9 @@ done:
}
int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
- struct group_filter __user *optval, int __user *optlen)
+ sockptr_t optval, size_t ss_offset)
{
- int err, i, count, copycount;
+ int i, count, copycount;
struct sockaddr_in *psin;
__be32 addr;
struct ip_mc_socklist *pmc;
@@ -2585,24 +2608,18 @@ int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
if (!ipv4_is_multicast(addr))
return -EINVAL;
- err = -EADDRNOTAVAIL;
-
for_each_pmc_rtnl(inet, pmc) {
if (pmc->multi.imr_multiaddr.s_addr == addr &&
pmc->multi.imr_ifindex == gsf->gf_interface)
break;
}
if (!pmc) /* must have a prior join */
- goto done;
+ return -EADDRNOTAVAIL;
gsf->gf_fmode = pmc->sfmode;
psl = rtnl_dereference(pmc->sflist);
count = psl ? psl->sl_count : 0;
copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
gsf->gf_numsrc = count;
- if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
- copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
- return -EFAULT;
- }
for (i = 0; i < copycount; i++) {
struct sockaddr_storage ss;
@@ -2610,12 +2627,12 @@ int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
memset(&ss, 0, sizeof(ss));
psin->sin_family = AF_INET;
psin->sin_addr.s_addr = psl->sl_addr[i];
- if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
+ if (copy_to_sockptr_offset(optval, ss_offset,
+ &ss, sizeof(ss)))
return -EFAULT;
+ ss_offset += sizeof(ss);
}
return 0;
-done:
- return err;
}
/*
@@ -2722,6 +2739,7 @@ int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u
rv = 1;
} else if (im) {
if (src_addr) {
+ spin_lock_bh(&im->lock);
for (psf = im->sources; psf; psf = psf->sf_next) {
if (psf->sf_inaddr == src_addr)
break;
@@ -2732,6 +2750,7 @@ int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u
im->sfcount[MCAST_EXCLUDE];
else
rv = im->sfcount[MCAST_EXCLUDE] != 0;
+ spin_unlock_bh(&im->lock);
} else
rv = 1; /* unspecified source; tentatively allow */
}
@@ -2831,7 +2850,7 @@ static int igmp_mc_seq_show(struct seq_file *seq, void *v)
seq_puts(seq,
"Idx\tDevice : Count Querier\tGroup Users Timer\tReporter\n");
else {
- struct ip_mc_list *im = (struct ip_mc_list *)v;
+ struct ip_mc_list *im = v;
struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
char *querier;
long delta;
@@ -2975,7 +2994,7 @@ static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
{
- struct ip_sf_list *psf = (struct ip_sf_list *)v;
+ struct ip_sf_list *psf = v;
struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
if (v == SEQ_START_TOKEN) {