FAILED: patch "[PATCH] Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()" failed to apply to 5.15-stable tree

index 21ebd70f3dcc..de530262d824 100644
@@ -1665,6 +1665,15 @@ struct hci_cp_le_set_event_mask {
 	__u8     mask[8];
 } __packed;
 
+/* BLUETOOTH CORE SPECIFICATION Version 5.4 | Vol 4, Part E
+ * 7.8.2 LE Read Buffer Size command
+ * MAX_LE_MTU is 0xffff.
+ * 0 is also valid. It means that no dedicated LE Buffer exists.
+ * It should use the HCI_Read_Buffer_Size command and mtu is shared
+ * between BR/EDR and LE.
+ */
+#define HCI_MIN_LE_MTU 0x001b
+
 #define HCI_OP_LE_READ_BUFFER_SIZE	0x2002
 struct hci_rp_le_read_buffer_size {
 	__u8     status;

index 2283d12ee358..be012f393bcb 100644
@@ -706,6 +706,7 @@ struct hci_conn {
 	__u16		handle;
 	__u16		sync_handle;
 	__u16		state;
+	__u16		mtu;
 	__u8		mode;
 	__u8		type;
 	__u8		role;

165 lines not on this page · raw message

index 122a6a9092e0..97c6f34ba640 100644
@@ -954,6 +954,9 @@ static u8 hci_cc_read_buffer_size(struct hci_dev *hdev, void *data,
 	BT_DBG("%s acl mtu %d:%d sco mtu %d:%d", hdev->name, hdev->acl_mtu,
 	       hdev->acl_pkts, hdev->sco_mtu, hdev->sco_pkts);
 
+	if (!hdev->acl_mtu || !hdev->acl_pkts)
+		return HCI_ERROR_INVALID_PARAMETERS;
+
 	return rp->status;
 }
 

@@ -1263,6 +1266,9 @@ static u8 hci_cc_le_read_buffer_size(struct hci_dev *hdev, void *data,
 
 	BT_DBG("%s le mtu %d:%d", hdev->name, hdev->le_mtu, hdev->le_pkts);
 
+	if (hdev->le_mtu && hdev->le_mtu < HCI_MIN_LE_MTU)
+		return HCI_ERROR_INVALID_PARAMETERS;
+
 	return rp->status;
 }
 

@@ -2341,8 +2347,8 @@ static void hci_cs_create_conn(struct hci_dev *hdev, __u8 status)
 		if (!conn) {
 			conn = hci_conn_add_unset(hdev, ACL_LINK, &cp->bdaddr,
 						  HCI_ROLE_MASTER);
-			if (!conn)
-				bt_dev_err(hdev, "no memory for new connection");
+			if (IS_ERR(conn))
+				bt_dev_err(hdev, "connection err: %ld", PTR_ERR(conn));
 		}
 	}
 

@@ -3153,8 +3159,8 @@ static void hci_conn_complete_evt(struct hci_dev *hdev, void *data,
 						      BDADDR_BREDR)) {
 			conn = hci_conn_add_unset(hdev, ev->link_type,
 						  &ev->bdaddr, HCI_ROLE_SLAVE);
-			if (!conn) {
-				bt_dev_err(hdev, "no memory for new conn");
+			if (IS_ERR(conn)) {
+				bt_dev_err(hdev, "connection err: %ld", PTR_ERR(conn));
 				goto unlock;
 			}
 		} else {

@@ -3342,8 +3348,8 @@ static void hci_conn_request_evt(struct hci_dev *hdev, void *data,
 	if (!conn) {
 		conn = hci_conn_add_unset(hdev, ev->link_type, &ev->bdaddr,
 					  HCI_ROLE_SLAVE);
-		if (!conn) {
-			bt_dev_err(hdev, "no memory for new connection");
+		if (IS_ERR(conn)) {
+			bt_dev_err(hdev, "connection err: %ld", PTR_ERR(conn));
 			goto unlock;
 		}
 	}

@@ -3820,6 +3826,9 @@ static u8 hci_cc_le_read_buffer_size_v2(struct hci_dev *hdev, void *data,
 	BT_DBG("%s acl mtu %d:%d iso mtu %d:%d", hdev->name, hdev->acl_mtu,
 	       hdev->acl_pkts, hdev->iso_mtu, hdev->iso_pkts);
 
+	if (hdev->le_mtu && hdev->le_mtu < HCI_MIN_LE_MTU)
+		return HCI_ERROR_INVALID_PARAMETERS;
+
 	return rp->status;
 }
 

@@ -5768,8 +5777,8 @@ static void le_conn_complete_evt(struct hci_dev *hdev, u8 status,
 			goto unlock;
 
 		conn = hci_conn_add_unset(hdev, LE_LINK, bdaddr, role);
-		if (!conn) {
-			bt_dev_err(hdev, "no memory for new connection");
+		if (IS_ERR(conn)) {
+			bt_dev_err(hdev, "connection err: %ld", PTR_ERR(conn));
 			goto unlock;
 		}
 

@@ -6497,7 +6506,7 @@ static void hci_le_pa_sync_estabilished_evt(struct hci_dev *hdev, void *data,
 	pa_sync = hci_conn_add_unset(hdev, ISO_LINK, BDADDR_ANY,
 				     HCI_ROLE_SLAVE);
 
-	if (!pa_sync)
+	if (IS_ERR(pa_sync))
 		goto unlock;
 
 	pa_sync->sync_handle = le16_to_cpu(ev->handle);

@@ -6921,7 +6930,7 @@ static void hci_le_cis_req_evt(struct hci_dev *hdev, void *data,
 	if (!cis) {
 		cis = hci_conn_add(hdev, ISO_LINK, &acl->dst, HCI_ROLE_SLAVE,
 				   cis_handle);
-		if (!cis) {
+		if (IS_ERR(cis)) {
 			hci_le_reject_cis(hdev, ev->cis_handle);
 			goto unlock;
 		}

@@ -7030,7 +7039,7 @@ static void hci_le_big_sync_established_evt(struct hci_dev *hdev, void *data,
 		if (!bis) {
 			bis = hci_conn_add(hdev, ISO_LINK, BDADDR_ANY,
 					   HCI_ROLE_SLAVE, handle);
-			if (!bis)
+			if (IS_ERR(bis))
 				continue;
 		}
 

index d0ef7290e5b7..00c0d8413c63 100644
@@ -1258,7 +1258,7 @@ static int iso_sock_sendmsg(struct socket *sock, struct msghdr *msg,
 		return -ENOTCONN;
 	}
 
-	mtu = iso_pi(sk)->conn->hcon->hdev->iso_mtu;
+	mtu = iso_pi(sk)->conn->hcon->mtu;
 
 	release_sock(sk);
 

index 443423538a4c..adc8f990f13e 100644
@@ -6264,7 +6264,7 @@ static int l2cap_finish_move(struct l2cap_chan *chan)
 	BT_DBG("chan %p", chan);
 
 	chan->rx_state = L2CAP_RX_STATE_RECV;
-	chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
+	chan->conn->mtu = chan->conn->hcon->mtu;
 
 	return l2cap_resegment(chan);
 }

@@ -6331,7 +6331,7 @@ static int l2cap_rx_state_wait_f(struct l2cap_chan *chan,
 	 */
 	chan->next_tx_seq = control->reqseq;
 	chan->unacked_frames = 0;
-	chan->conn->mtu = chan->conn->hcon->hdev->acl_mtu;
+	chan->conn->mtu = chan->conn->hcon->mtu;
 
 	err = l2cap_resegment(chan);
 

@@ -6889,18 +6889,7 @@ static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon)
 
 	BT_DBG("hcon %p conn %p hchan %p", hcon, conn, hchan);
 
-	switch (hcon->type) {
-	case LE_LINK:
-		if (hcon->hdev->le_mtu) {
-			conn->mtu = hcon->hdev->le_mtu;
-			break;
-		}
-		fallthrough;
-	default:
-		conn->mtu = hcon->hdev->acl_mtu;
-		break;
-	}
-
+	conn->mtu = hcon->mtu;
 	conn->feat_mask = 0;
 
 	conn->local_fixed_chan = L2CAP_FC_SIG_BREDR | L2CAP_FC_CONNLESS;

index e0ad30862ee4..71d36582d4ef 100644
@@ -126,7 +126,6 @@ static void sco_sock_clear_timer(struct sock *sk)
 /* ---- SCO connections ---- */
 static struct sco_conn *sco_conn_add(struct hci_conn *hcon)
 {
-	struct hci_dev *hdev = hcon->hdev;
 	struct sco_conn *conn = hcon->sco_data;
 
 	if (conn) {

@@ -144,9 +143,10 @@ static struct sco_conn *sco_conn_add(struct hci_conn *hcon)
 
 	hcon->sco_data = conn;
 	conn->hcon = hcon;
+	conn->mtu = hcon->mtu;
 
-	if (hdev->sco_mtu > 0)
-		conn->mtu = hdev->sco_mtu;
+	if (hcon->mtu > 0)
+		conn->mtu = hcon->mtu;
 	else
 		conn->mtu = 60;