1 files changed, 28 insertions, 16 deletions

diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c
index 793a481d7066..2e95a153912c 100644
--- a/net/bluetooth/iso.c
+++ b/net/bluetooth/iso.c
@@ -1590,6 +1590,7 @@ static void iso_conn_big_sync(struct sock *sk)
 {
 	int err;
 	struct hci_dev *hdev;
+	struct iso_conn *conn;
 	bdaddr_t src, dst;
 	u8 src_type;
 
@@ -1612,8 +1613,17 @@ static void iso_conn_big_sync(struct sock *sk)
 	hci_dev_lock(hdev);
 	lock_sock(sk);
 
+	/* The socket lock was dropped for hci_get_route(), so the connection
+	 * may have been torn down meanwhile: iso_chan_del() clears conn and
+	 * the broadcast teardown path can clear conn->hcon on its own. Check
+	 * both before dereferencing conn->hcon.
+	 */
+	conn = iso_pi(sk)->conn;
+	if (!conn || !conn->hcon)
+		goto unlock;
+
 	if (!test_and_set_bit(BT_SK_BIG_SYNC, &iso_pi(sk)->flags)) {
-		err = hci_conn_big_create_sync(hdev, iso_pi(sk)->conn->hcon,
+		err = hci_conn_big_create_sync(hdev, conn->hcon,
 					       &iso_pi(sk)->qos,
 					       iso_pi(sk)->sync_handle,
 					       iso_pi(sk)->bc_num_bis,
@@ -1622,6 +1632,7 @@ static void iso_conn_big_sync(struct sock *sk)
 			bt_dev_err(hdev, "hci_big_create_sync: %d", err);
 	}
 
+unlock:
 	release_sock(sk);
 	hci_dev_unlock(hdev);
 	hci_dev_put(hdev);
@@ -2529,7 +2540,7 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 	switch (pb) {
 	case ISO_START:
 	case ISO_SINGLE:
-		if (conn->rx_len) {
+		if (conn->rx_skb || conn->rx_len) {
 			BT_ERR("Unexpected start frame (len %d)", skb->len);
 			kfree_skb(conn->rx_skb);
 			conn->rx_skb = NULL;
@@ -2610,12 +2621,14 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 		break;
 
 	case ISO_CONT:
-		BT_DBG("Cont: frag len %d (expecting %d)", skb->len,
+	case ISO_END:
+		BT_DBG("%s: frag len %d (expecting %d)",
+		       (pb == ISO_END) ? "End" : "Cont", skb->len,
 		       conn->rx_len);
 
-		if (!conn->rx_len) {
-			BT_ERR("Unexpected continuation frame (len %d)",
-			       skb->len);
+		if (!conn->rx_skb) {
+			BT_ERR("Unexpected ISO %s frame (len %d)",
+			       (pb == ISO_END) ? "End" : "Cont", skb->len);
 			goto drop;
 		}
 
@@ -2631,17 +2644,9 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 		skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
 					  skb->len);
 		conn->rx_len -= skb->len;
-		break;
-
-	case ISO_END:
-		if (!conn->rx_len) {
-			BT_ERR("Unexpected end frame (len %d)", skb->len);
-			goto drop;
-		}
 
-		skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
-					  skb->len);
-		conn->rx_len -= skb->len;
+		if (pb == ISO_CONT)
+			break;
 
 		if (!conn->rx_len) {
 			struct sk_buff *rx_skb = conn->rx_skb;
@@ -2652,6 +2657,13 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 			 */
 			conn->rx_skb = NULL;
 			iso_recv_frame(conn, rx_skb);
+		} else {
+			BT_ERR("ISO fragment incomplete (len %d, expected %d)",
+			       skb->len, conn->rx_len);
+			kfree_skb(conn->rx_skb);
+			conn->rx_skb = NULL;
+			conn->rx_len = 0;
+			goto drop;
 		}
 		break;
 	}