2 files changed, 75 insertions, 14 deletions

diff --git a/net/batman-adv/Kconfig b/net/batman-adv/Kconfig
index f66930ee3c0b..b7ba97dbf4a9 100644
--- a/net/batman-adv/Kconfig
+++ b/net/batman-adv/Kconfig
@@ -66,7 +66,7 @@ config BATMAN_ADV_NC
 
 config BATMAN_ADV_MCAST
         bool "Multicast optimisation"
-        depends on BATMAN_ADV
+        depends on BATMAN_ADV && INET
         default n
         help
           This option enables the multicast optimisation which aims to
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
index c32f24fafe67..4673328def29 100644
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -25,9 +25,11 @@
 #include <linux/errno.h>
 #include <linux/etherdevice.h>
 #include <linux/fs.h>
+#include <linux/icmpv6.h>
 #include <linux/if_ether.h>
-#include <linux/in6.h>
+#include <linux/igmp.h>
 #include <linux/in.h>
+#include <linux/in6.h>
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/kref.h>
@@ -236,7 +238,7 @@ static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv)
         if (batadv_mcast_has_bridge(bat_priv)) {
                 if (bat_priv->mcast.enabled) {
                         batadv_tvlv_container_unregister(bat_priv,
-                                                         BATADV_TVLV_MCAST, 1);
+                                                         BATADV_TVLV_MCAST, 2);
                         bat_priv->mcast.enabled = false;
                 }
 
@@ -245,7 +247,7 @@ static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv)
 
         if (!bat_priv->mcast.enabled ||
             mcast_data.flags != bat_priv->mcast.flags) {
-                batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 1,
+                batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 2,
                                                &mcast_data, sizeof(mcast_data));
                 bat_priv->mcast.flags = mcast_data.flags;
                 bat_priv->mcast.enabled = true;
@@ -283,6 +285,31 @@ out:
 }
 
 /**
+ * batadv_mcast_is_report_ipv4 - check for IGMP reports
+ * @skb: the ethernet frame destined for the mesh
+ *
+ * This call might reallocate skb data.
+ *
+ * Checks whether the given frame is a valid IGMP report.
+ *
+ * Return: If so then true, otherwise false.
+ */
+static bool batadv_mcast_is_report_ipv4(struct sk_buff *skb)
+{
+        if (ip_mc_check_igmp(skb, NULL) < 0)
+                return false;
+
+        switch (igmp_hdr(skb)->type) {
+        case IGMP_HOST_MEMBERSHIP_REPORT:
+        case IGMPV2_HOST_MEMBERSHIP_REPORT:
+        case IGMPV3_HOST_MEMBERSHIP_REPORT:
+                return true;
+        }
+
+        return false;
+}
+
+/**
  * batadv_mcast_forw_mode_check_ipv4 - check for optimized forwarding potential
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the IPv4 packet to check
@@ -304,6 +331,9 @@ static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
         if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
                 return -ENOMEM;
 
+        if (batadv_mcast_is_report_ipv4(skb))
+                return -EINVAL;
+
         iphdr = ip_hdr(skb);
 
         /* TODO: Implement Multicast Router Discovery (RFC4286),
@@ -320,6 +350,31 @@ static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
         return 0;
 }
 
+#if IS_ENABLED(CONFIG_IPV6)
+/**
+ * batadv_mcast_is_report_ipv6 - check for MLD reports
+ * @skb: the ethernet frame destined for the mesh
+ *
+ * This call might reallocate skb data.
+ *
+ * Checks whether the given frame is a valid MLD report.
+ *
+ * Return: If so then true, otherwise false.
+ */
+static bool batadv_mcast_is_report_ipv6(struct sk_buff *skb)
+{
+        if (ipv6_mc_check_mld(skb, NULL) < 0)
+                return false;
+
+        switch (icmp6_hdr(skb)->icmp6_type) {
+        case ICMPV6_MGM_REPORT:
+        case ICMPV6_MLD2_REPORT:
+                return true;
+        }
+
+        return false;
+}
+
 /**
  * batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential
  * @bat_priv: the bat priv with all the soft interface information
@@ -341,6 +396,9 @@ static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
         if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr)))
                 return -ENOMEM;
 
+        if (batadv_mcast_is_report_ipv6(skb))
+                return -EINVAL;
+
         ip6hdr = ipv6_hdr(skb);
 
         /* TODO: Implement Multicast Router Discovery (RFC4286),
@@ -357,6 +415,7 @@ static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
 
         return 0;
 }
+#endif
 
 /**
  * batadv_mcast_forw_mode_check - check for optimized forwarding potential
@@ -385,9 +444,11 @@ static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
         case ETH_P_IP:
                 return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
                                                          is_unsnoopable);
+#if IS_ENABLED(CONFIG_IPV6)
         case ETH_P_IPV6:
                 return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
                                                          is_unsnoopable);
+#endif
         default:
                 return -EINVAL;
         }
@@ -728,18 +789,18 @@ static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv,
 }
 
 /**
- * batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container
+ * batadv_mcast_tvlv_ogm_handler - process incoming multicast tvlv container
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node of the ogm
  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
  * @tvlv_value: tvlv buffer containing the multicast data
  * @tvlv_value_len: tvlv buffer length
  */
-static void batadv_mcast_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
-                                             struct batadv_orig_node *orig,
-                                             u8 flags,
-                                             void *tvlv_value,
-                                             u16 tvlv_value_len)
+static void batadv_mcast_tvlv_ogm_handler(struct batadv_priv *bat_priv,
+                                          struct batadv_orig_node *orig,
+                                          u8 flags,
+                                          void *tvlv_value,
+                                          u16 tvlv_value_len)
 {
         bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
         u8 mcast_flags = BATADV_NO_FLAGS;
@@ -789,8 +850,8 @@ static void batadv_mcast_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
  */
 void batadv_mcast_init(struct batadv_priv *bat_priv)
 {
-        batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler_v1,
-                                     NULL, BATADV_TVLV_MCAST, 1,
+        batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler,
+                                     NULL, BATADV_TVLV_MCAST, 2,
                                      BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
 }
 
@@ -800,8 +861,8 @@ void batadv_mcast_init(struct batadv_priv *bat_priv)
  */
 void batadv_mcast_free(struct batadv_priv *bat_priv)
 {
-        batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 1);
-        batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 1);
+        batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
+        batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 2);
 
         spin_lock_bh(&bat_priv->tt.commit_lock);
         batadv_mcast_mla_tt_retract(bat_priv, NULL);