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Diffstat (limited to 'net/ipv4/igmp.c')
-rw-r--r--net/ipv4/igmp.c77
1 files changed, 58 insertions, 19 deletions
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index b3086cf27027..c67efa3e79dd 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -89,6 +89,7 @@
#include <linux/rtnetlink.h>
#include <linux/times.h>
#include <linux/pkt_sched.h>
+#include <linux/byteorder/generic.h>
#include <net/net_namespace.h>
#include <net/arp.h>
@@ -225,9 +226,14 @@ 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;
+ unsigned long exp = jiffies + tv + 2;
+
+ if (in_dev->mr_gq_running &&
+ time_after_eq(exp, (in_dev->mr_gq_timer).expires))
+ return;
in_dev->mr_gq_running = 1;
- if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
+ if (!mod_timer(&in_dev->mr_gq_timer, exp))
in_dev_hold(in_dev);
}
@@ -322,6 +328,23 @@ igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
return scount;
}
+/* source address selection per RFC 3376 section 4.2.13 */
+static __be32 igmpv3_get_srcaddr(struct net_device *dev,
+ const struct flowi4 *fl4)
+{
+ struct in_device *in_dev = __in_dev_get_rcu(dev);
+
+ if (!in_dev)
+ return htonl(INADDR_ANY);
+
+ for_ifa(in_dev) {
+ if (fl4->saddr == ifa->ifa_local)
+ return fl4->saddr;
+ } endfor_ifa(in_dev);
+
+ return htonl(INADDR_ANY);
+}
+
static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
{
struct sk_buff *skb;
@@ -369,7 +392,11 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
pip->frag_off = htons(IP_DF);
pip->ttl = 1;
pip->daddr = fl4.daddr;
- pip->saddr = fl4.saddr;
+
+ rcu_read_lock();
+ pip->saddr = igmpv3_get_srcaddr(dev, &fl4);
+ rcu_read_unlock();
+
pip->protocol = IPPROTO_IGMP;
pip->tot_len = 0; /* filled in later */
ip_select_ident(net, skb, NULL);
@@ -405,16 +432,17 @@ static int grec_size(struct ip_mc_list *pmc, int type, int gdel, int sdel)
}
static struct sk_buff *add_grhead(struct sk_buff *skb, struct ip_mc_list *pmc,
- int type, struct igmpv3_grec **ppgr)
+ int type, struct igmpv3_grec **ppgr, unsigned int mtu)
{
struct net_device *dev = pmc->interface->dev;
struct igmpv3_report *pih;
struct igmpv3_grec *pgr;
- if (!skb)
- skb = igmpv3_newpack(dev, dev->mtu);
- if (!skb)
- return NULL;
+ if (!skb) {
+ skb = igmpv3_newpack(dev, mtu);
+ if (!skb)
+ return NULL;
+ }
pgr = (struct igmpv3_grec *)skb_put(skb, sizeof(struct igmpv3_grec));
pgr->grec_type = type;
pgr->grec_auxwords = 0;
@@ -436,12 +464,17 @@ static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
struct igmpv3_grec *pgr = NULL;
struct ip_sf_list *psf, *psf_next, *psf_prev, **psf_list;
int scount, stotal, first, isquery, truncate;
+ unsigned int mtu;
if (pmc->multiaddr == IGMP_ALL_HOSTS)
return skb;
if (ipv4_is_local_multicast(pmc->multiaddr) && !sysctl_igmp_llm_reports)
return skb;
+ mtu = READ_ONCE(dev->mtu);
+ if (mtu < IPV4_MIN_MTU)
+ return skb;
+
isquery = type == IGMPV3_MODE_IS_INCLUDE ||
type == IGMPV3_MODE_IS_EXCLUDE;
truncate = type == IGMPV3_MODE_IS_EXCLUDE ||
@@ -462,7 +495,7 @@ static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
if (skb)
igmpv3_sendpack(skb);
- skb = igmpv3_newpack(dev, dev->mtu);
+ skb = igmpv3_newpack(dev, mtu);
}
}
first = 1;
@@ -489,12 +522,12 @@ static struct sk_buff *add_grec(struct sk_buff *skb, struct ip_mc_list *pmc,
pgr->grec_nsrcs = htons(scount);
if (skb)
igmpv3_sendpack(skb);
- skb = igmpv3_newpack(dev, dev->mtu);
+ skb = igmpv3_newpack(dev, mtu);
first = 1;
scount = 0;
}
if (first) {
- skb = add_grhead(skb, pmc, type, &pgr);
+ skb = add_grhead(skb, pmc, type, &pgr, mtu);
first = 0;
}
if (!skb)
@@ -528,7 +561,7 @@ empty_source:
igmpv3_sendpack(skb);
skb = NULL; /* add_grhead will get a new one */
}
- skb = add_grhead(skb, pmc, type, &pgr);
+ skb = add_grhead(skb, pmc, type, &pgr, mtu);
}
}
if (pgr)
@@ -1097,6 +1130,7 @@ static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
pmc = kzalloc(sizeof(*pmc), GFP_KERNEL);
if (!pmc)
return;
+ spin_lock_init(&pmc->lock);
spin_lock_bh(&im->lock);
pmc->interface = im->interface;
in_dev_hold(in_dev);
@@ -2021,21 +2055,26 @@ static int ip_mc_add_src(struct in_device *in_dev, __be32 *pmca, int sfmode,
static void ip_mc_clear_src(struct ip_mc_list *pmc)
{
- struct ip_sf_list *psf, *nextpsf;
+ struct ip_sf_list *psf, *nextpsf, *tomb, *sources;
- for (psf = pmc->tomb; psf; psf = nextpsf) {
+ spin_lock_bh(&pmc->lock);
+ tomb = pmc->tomb;
+ pmc->tomb = NULL;
+ sources = pmc->sources;
+ pmc->sources = NULL;
+ pmc->sfmode = MCAST_EXCLUDE;
+ pmc->sfcount[MCAST_INCLUDE] = 0;
+ pmc->sfcount[MCAST_EXCLUDE] = 1;
+ spin_unlock_bh(&pmc->lock);
+
+ for (psf = tomb; psf; psf = nextpsf) {
nextpsf = psf->sf_next;
kfree(psf);
}
- pmc->tomb = NULL;
- for (psf = pmc->sources; psf; psf = nextpsf) {
+ for (psf = sources; psf; psf = nextpsf) {
nextpsf = psf->sf_next;
kfree(psf);
}
- pmc->sources = NULL;
- pmc->sfmode = MCAST_EXCLUDE;
- pmc->sfcount[MCAST_INCLUDE] = 0;
- pmc->sfcount[MCAST_EXCLUDE] = 1;
}
/* Join a multicast group
generated by cgit v1.2.3 (git 2.25.1) at 2025-12-10 22:45:58 +0000