Merge tag 'for-net-2026-03-25' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth

Luiz Augusto von Dentz says:

====================
bluetooth pull request for net:

 - L2CAP: Fix deadlock in l2cap_conn_del()
 - L2CAP: Fix ERTM re-init and zero pdu_len infinite loop
 - L2CAP: Fix send LE flow credits in ACL link
 - btintel: serialize btintel_hw_error() with hci_req_sync_lock
 - btusb: clamp SCO altsetting table indices

* tag 'for-net-2026-03-25' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth:
  Bluetooth: btusb: clamp SCO altsetting table indices
  Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop
  Bluetooth: L2CAP: Fix deadlock in l2cap_conn_del()
  Bluetooth: btintel: serialize btintel_hw_error() with hci_req_sync_lock
  Bluetooth: L2CAP: Fix send LE flow credits in ACL link
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Paolo Abeni <[email protected]>

Author: Paolo Abeni

drivers/bluetooth/btintel.c

@@ -251,30 +251,35 @@ void btintel_hw_error(struct hci_dev *hdev, u8 code)
 
 	bt_dev_err(hdev, "Hardware error 0x%2.2x", code);
 
+	hci_req_sync_lock(hdev);
+
 	skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_INIT_TIMEOUT);
 	if (IS_ERR(skb)) {
 		bt_dev_err(hdev, "Reset after hardware error failed (%ld)",
 			   PTR_ERR(skb));
-		return;
+		goto unlock;
 	}
 	kfree_skb(skb);
 
 	skb = __hci_cmd_sync(hdev, 0xfc22, 1, &type, HCI_INIT_TIMEOUT);
 	if (IS_ERR(skb)) {
 		bt_dev_err(hdev, "Retrieving Intel exception info failed (%ld)",
 			   PTR_ERR(skb));
-		return;
+		goto unlock;
 	}
 
 	if (skb->len != 13) {
 		bt_dev_err(hdev, "Exception info size mismatch");
 		kfree_skb(skb);
-		return;
+		goto unlock;
 	}
 
 	bt_dev_err(hdev, "Exception info %s", (char *)(skb->data + 1));
 
 	kfree_skb(skb);
+
+unlock:
+	hci_req_sync_unlock(hdev);
 }
 EXPORT_SYMBOL_GPL(btintel_hw_error);
 

drivers/bluetooth/btusb.c

@@ -2376,8 +2376,11 @@ static void btusb_work(struct work_struct *work)
 		if (data->air_mode == HCI_NOTIFY_ENABLE_SCO_CVSD) {
 			if (hdev->voice_setting & 0x0020) {
 				static const int alts[3] = { 2, 4, 5 };
+				unsigned int sco_idx;
 
-				new_alts = alts[data->sco_num - 1];
+				sco_idx = min_t(unsigned int, data->sco_num - 1,
+						ARRAY_SIZE(alts) - 1);
+				new_alts = alts[sco_idx];
 			} else {
 				new_alts = data->sco_num;
 			}

net/bluetooth/l2cap_core.c

@@ -1771,6 +1771,9 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err)
 
 	BT_DBG("hcon %p conn %p, err %d", hcon, conn, err);
 
+	disable_delayed_work_sync(&conn->info_timer);
+	disable_delayed_work_sync(&conn->id_addr_timer);
+
 	mutex_lock(&conn->lock);
 
 	kfree_skb(conn->rx_skb);
@@ -1786,8 +1789,6 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err)
 
 	ida_destroy(&conn->tx_ida);
 
-	cancel_delayed_work_sync(&conn->id_addr_timer);
-
 	l2cap_unregister_all_users(conn);
 
 	/* Force the connection to be immediately dropped */
@@ -1806,9 +1807,6 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err)
 		l2cap_chan_put(chan);
 	}
 
-	if (conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_SENT)
-		cancel_delayed_work_sync(&conn->info_timer);
-
 	hci_chan_del(conn->hchan);
 	conn->hchan = NULL;
 
@@ -2400,6 +2398,9 @@ static int l2cap_segment_sdu(struct l2cap_chan *chan,
 	/* Remote device may have requested smaller PDUs */
 	pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
 
+	if (!pdu_len)
+		return -EINVAL;
+
 	if (len <= pdu_len) {
 		sar = L2CAP_SAR_UNSEGMENTED;
 		sdu_len = 0;
@@ -4335,14 +4336,16 @@ static inline int l2cap_config_req(struct l2cap_conn *conn,
 	if (test_bit(CONF_INPUT_DONE, &chan->conf_state)) {
 		set_default_fcs(chan);
 
-		if (chan->mode == L2CAP_MODE_ERTM ||
-		    chan->mode == L2CAP_MODE_STREAMING)
-			err = l2cap_ertm_init(chan);
+		if (chan->state != BT_CONNECTED) {
+			if (chan->mode == L2CAP_MODE_ERTM ||
+			    chan->mode == L2CAP_MODE_STREAMING)
+				err = l2cap_ertm_init(chan);
 
-		if (err < 0)
-			l2cap_send_disconn_req(chan, -err);
-		else
-			l2cap_chan_ready(chan);
+			if (err < 0)
+				l2cap_send_disconn_req(chan, -err);
+			else
+				l2cap_chan_ready(chan);
+		}
 
 		goto unlock;
 	}
@@ -6630,6 +6633,10 @@ static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
 	struct l2cap_le_credits pkt;
 	u16 return_credits = l2cap_le_rx_credits(chan);
 
+	if (chan->mode != L2CAP_MODE_LE_FLOWCTL &&
+	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
+		return;
+
 	if (chan->rx_credits >= return_credits)
 		return;