1 files changed, 28 insertions, 21 deletions

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index b65d074d9620..e3ab0cb61624 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -467,7 +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);
@@ -593,7 +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])
@@ -736,7 +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)
@@ -825,7 +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;
-	WRITE_ONCE(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);
 }
 
@@ -920,7 +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();
@@ -1006,7 +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:
@@ -1045,7 +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)
@@ -1186,7 +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;
@@ -1237,9 +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);
@@ -1296,7 +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;
@@ -1338,13 +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);
@@ -1358,7 +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
@@ -1642,7 +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
@@ -1749,7 +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)
@@ -1883,7 +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;
@@ -1947,7 +1954,7 @@ 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;
+		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;
@@ -2126,7 +2133,7 @@ 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;
+		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;
@@ -2192,7 +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)
@@ -2379,7 +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;
 	}