3 files changed, 42 insertions, 21 deletions

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 8a1605ae4029..226b2cdfc339 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -207,24 +207,6 @@ static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
 		struct tpacket3_hdr *);
 static void packet_flush_mclist(struct sock *sk);
 
-#define PACKET_FANOUT_MAX	256
-
-struct packet_fanout {
-#ifdef CONFIG_NET_NS
-	struct net		*net;
-#endif
-	unsigned int		num_members;
-	u16			id;
-	u8			type;
-	u8			defrag;
-	atomic_t		rr_cur;
-	struct list_head	list;
-	struct sock		*arr[PACKET_FANOUT_MAX];
-	spinlock_t		lock;
-	atomic_t		sk_ref;
-	struct packet_type	prot_hook ____cacheline_aligned_in_smp;
-};
-
 struct packet_skb_cb {
 	unsigned int origlen;
 	union {
@@ -1148,7 +1130,8 @@ static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
 	return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
 }
 
-static DEFINE_MUTEX(fanout_mutex);
+DEFINE_MUTEX(fanout_mutex);
+EXPORT_SYMBOL_GPL(fanout_mutex);
 static LIST_HEAD(fanout_list);
 
 static void __fanout_link(struct sock *sk, struct packet_sock *po)
@@ -1260,9 +1243,9 @@ static void fanout_release(struct sock *sk)
 	if (!f)
 		return;
 
+	mutex_lock(&fanout_mutex);
 	po->fanout = NULL;
 
-	mutex_lock(&fanout_mutex);
 	if (atomic_dec_and_test(&f->sk_ref)) {
 		list_del(&f->list);
 		dev_remove_pack(&f->prot_hook);
diff --git a/net/packet/diag.c b/net/packet/diag.c
index e3975e4d458c..bc33fbe8a5ef 100644
--- a/net/packet/diag.c
+++ b/net/packet/diag.c
@@ -109,6 +109,22 @@ static int pdiag_put_rings_cfg(struct packet_sock *po, struct sk_buff *skb)
 	return ret;
 }
 
+static int pdiag_put_fanout(struct packet_sock *po, struct sk_buff *nlskb)
+{
+	int ret = 0;
+
+	mutex_lock(&fanout_mutex);
+	if (po->fanout) {
+		u32 val;
+
+		val = (u32)po->fanout->id | ((u32)po->fanout->type << 16);
+		ret = nla_put_u32(nlskb, PACKET_DIAG_FANOUT, val);
+	}
+	mutex_unlock(&fanout_mutex);
+
+	return ret;
+}
+
 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct packet_diag_req *req,
 		u32 pid, u32 seq, u32 flags, int sk_ino)
 {
@@ -139,6 +155,10 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct packet_diag
 			pdiag_put_rings_cfg(po, skb))
 		goto out_nlmsg_trim;
 
+	if ((req->pdiag_show & PACKET_SHOW_FANOUT) &&
+			pdiag_put_fanout(po, skb))
+		goto out_nlmsg_trim;
+
 	return nlmsg_end(skb, nlh);
 
 out_nlmsg_trim:
diff --git a/net/packet/internal.h b/net/packet/internal.h
index 2c5fca28b242..44945f6b7252 100644
--- a/net/packet/internal.h
+++ b/net/packet/internal.h
@@ -67,7 +67,25 @@ struct packet_ring_buffer {
 	atomic_t		pending;
 };
 
-struct packet_fanout;
+extern struct mutex fanout_mutex;
+#define PACKET_FANOUT_MAX	256
+
+struct packet_fanout {
+#ifdef CONFIG_NET_NS
+	struct net		*net;
+#endif
+	unsigned int		num_members;
+	u16			id;
+	u8			type;
+	u8			defrag;
+	atomic_t		rr_cur;
+	struct list_head	list;
+	struct sock		*arr[PACKET_FANOUT_MAX];
+	spinlock_t		lock;
+	atomic_t		sk_ref;
+	struct packet_type	prot_hook ____cacheline_aligned_in_smp;
+};
+
 struct packet_sock {
 	/* struct sock has to be the first member of packet_sock */
 	struct sock		sk;