Multiple gatt connection patch to kernel 3.2

kernel_3.2_gatt.patch

--- linux-3.2.orig/net/bluetooth/l2cap_core.c	2015-05-25 15:13:25.035952220 +0200
+++ linux-3.2/net/bluetooth/l2cap_core.c	2015-07-07 13:07:02.915456939 +0200
@@ -800,11 +800,14 @@ static void l2cap_conn_start(struct l2ca
 /* Find socket with cid and source bdaddr.
  * Returns closest match, locked.
  */
-static struct l2cap_chan *l2cap_global_chan_by_scid(int state, __le16 cid, bdaddr_t *src)
+static struct l2cap_chan *l2cap_global_chan_by_scid(int state, __le16 cid, bdaddr_t *src, bdaddr_t *dst)
 {
 	struct l2cap_chan *c, *c1 = NULL;
 
 	read_lock(&chan_list_lock);
+	
+	BT_DBG("%s -> %s cid %d", batostr(src), batostr(dst), cid);
+
 
 	list_for_each_entry(c, &chan_list, global_l) {
 		struct sock *sk = c->sk;
@@ -813,14 +816,23 @@ static struct l2cap_chan *l2cap_global_c
 			continue;
 
 		if (c->scid == cid) {
+			int src_match, dst_match;
+			int src_any, dst_any;
+			
+			src_match = !bacmp(&bt_sk(sk)->src, src);
+			dst_match = !bacmp(&bt_sk(sk)->dst, dst);
+			BT_DBG("test: src: %s dst: %s", batostr(&bt_sk(sk)->src), batostr(&bt_sk(sk)->dst));
 			/* Exact match. */
-			if (!bacmp(&bt_sk(sk)->src, src)) {
+			if (src_match && dst_match) {
 				read_unlock(&chan_list_lock);
 				return c;
 			}
 
 			/* Closest match */
-			if (!bacmp(&bt_sk(sk)->src, BDADDR_ANY))
+			src_any = !bacmp(&bt_sk(sk)->src, BDADDR_ANY);
+			dst_any = !bacmp(&bt_sk(sk)->dst, BDADDR_ANY);
+			if ((src_match && dst_any) || (src_any && dst_match) ||
+			    (src_any && dst_any))
 				c1 = c;
 		}
 	}
@@ -839,7 +851,7 @@ static void l2cap_le_conn_ready(struct l
 
 	/* Check if we have socket listening on cid */
 	pchan = l2cap_global_chan_by_scid(BT_LISTEN, L2CAP_CID_LE_DATA,
-							conn->src);
+							conn->src, conn->dst);
 	if (!pchan)
 		return;
 
@@ -3849,7 +3861,7 @@ static inline int l2cap_att_channel(stru
 	struct sock *sk = NULL;
 	struct l2cap_chan *chan;
 
-	chan = l2cap_global_chan_by_scid(0, cid, conn->src);
+	chan = l2cap_global_chan_by_scid(0, cid, conn->src, conn->dst);
 	if (!chan)
 		goto drop;

If you connect to more than one device via e.g. gatttool then second connection will receive responses performed from first connection.
This patch solves the problem and also it's been already solved in kernel 3.5