Merge tag 'for-net-2025-11-21' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth

Luiz Augusto von Dentz says:

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

 - hci_sock: Prevent race in socket write iter and sock bind
 - hci_core: Fix triggering cmd_timer for HCI_OP_NOP
 - hci_core: lookup hci_conn on RX path on protocol side
 - SMP: Fix not generating mackey and ltk when repairing
 - btusb: mediatek: Fix kernel crash when releasing mtk iso interface
 - btusb: mediatek: Avoid btusb_mtk_claim_iso_intf() NULL deref

* tag 'for-net-2025-11-21' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth:
  Bluetooth: SMP: Fix not generating mackey and ltk when repairing
  Bluetooth: btusb: mediatek: Avoid btusb_mtk_claim_iso_intf() NULL deref
  Bluetooth: hci_core: lookup hci_conn on RX path on protocol side
  Bluetooth: hci_sock: Prevent race in socket write iter and sock bind
  Bluetooth: hci_core: Fix triggering cmd_timer for HCI_OP_NOP
  Bluetooth: btusb: mediatek: Fix kernel crash when releasing mtk iso interface
====================

Link: https://patch.msgid.link/20251121145332.177015-1-luiz.dentz@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/bluetooth/btusb.c

@@ -2711,9 +2711,21 @@ static int btusb_recv_event_realtek(struct hci_dev *hdev, struct sk_buff *skb)
 
 static void btusb_mtk_claim_iso_intf(struct btusb_data *data)
 {
-	struct btmtk_data *btmtk_data = hci_get_priv(data->hdev);
+	struct btmtk_data *btmtk_data;
 	int err;
 
+	if (!data->hdev)
+		return;
+
+	btmtk_data = hci_get_priv(data->hdev);
+	if (!btmtk_data)
+		return;
+
+	if (!btmtk_data->isopkt_intf) {
+		bt_dev_err(data->hdev, "Can't claim NULL iso interface");
+		return;
+	}
+
 	/*
 	 * The function usb_driver_claim_interface() is documented to need
 	 * locks held if it's not called from a probe routine. The code here
@@ -2735,17 +2747,30 @@ static void btusb_mtk_claim_iso_intf(struct btusb_data *data)
 
 static void btusb_mtk_release_iso_intf(struct hci_dev *hdev)
 {
-	struct btmtk_data *btmtk_data = hci_get_priv(hdev);
+	struct btmtk_data *btmtk_data;
+
+	if (!hdev)
+		return;
+
+	btmtk_data = hci_get_priv(hdev);
+	if (!btmtk_data)
+		return;
 
 	if (test_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags)) {
 		usb_kill_anchored_urbs(&btmtk_data->isopkt_anchor);
 		clear_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags);
 
-		dev_kfree_skb_irq(btmtk_data->isopkt_skb);
-		btmtk_data->isopkt_skb = NULL;
-		usb_set_intfdata(btmtk_data->isopkt_intf, NULL);
-		usb_driver_release_interface(&btusb_driver,
-					     btmtk_data->isopkt_intf);
+		if (btmtk_data->isopkt_skb) {
+			dev_kfree_skb_irq(btmtk_data->isopkt_skb);
+			btmtk_data->isopkt_skb = NULL;
+		}
+
+		if (btmtk_data->isopkt_intf) {
+			usb_set_intfdata(btmtk_data->isopkt_intf, NULL);
+			usb_driver_release_interface(&btusb_driver,
+						     btmtk_data->isopkt_intf);
+			btmtk_data->isopkt_intf = NULL;
+		}
 	}
 
 	clear_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags);

include/net/bluetooth/hci_core.h

@@ -749,7 +749,6 @@ struct hci_conn {
 
 	__u8		remote_cap;
 	__u8		remote_auth;
-	__u8		remote_id;
 
 	unsigned int	sent;
 
@@ -857,11 +856,12 @@ extern struct mutex hci_cb_list_lock;
 /* ----- HCI interface to upper protocols ----- */
 int l2cap_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr);
 int l2cap_disconn_ind(struct hci_conn *hcon);
-void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags);
+int l2cap_recv_acldata(struct hci_dev *hdev, u16 handle, struct sk_buff *skb,
+		       u16 flags);
 
 #if IS_ENABLED(CONFIG_BT_BREDR)
 int sco_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 *flags);
-void sco_recv_scodata(struct hci_conn *hcon, struct sk_buff *skb);
+int sco_recv_scodata(struct hci_dev *hdev, u16 handle, struct sk_buff *skb);
 #else
 static inline int sco_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr,
 				  __u8 *flags)
@@ -869,23 +869,30 @@ static inline int sco_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr,
 	return 0;
 }
 
-static inline void sco_recv_scodata(struct hci_conn *hcon, struct sk_buff *skb)
+static inline int sco_recv_scodata(struct hci_dev *hdev, u16 handle,
+				   struct sk_buff *skb)
 {
+	kfree_skb(skb);
+	return -ENOENT;
 }
 #endif
 
 #if IS_ENABLED(CONFIG_BT_LE)
 int iso_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 *flags);
-void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags);
+int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb,
+	     u16 flags);
 #else
 static inline int iso_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr,
 				  __u8 *flags)
 {
 	return 0;
 }
-static inline void iso_recv(struct hci_conn *hcon, struct sk_buff *skb,
-			    u16 flags)
+
+static inline int iso_recv(struct hci_dev *hdev, u16 handle,
+			   struct sk_buff *skb, u16 flags)
 {
+	kfree_skb(skb);
+	return -ENOENT;
 }
 #endif
 

net/bluetooth/hci_core.c

@@ -3832,13 +3832,14 @@ static void hci_tx_work(struct work_struct *work)
 static void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	struct hci_acl_hdr *hdr;
-	struct hci_conn *conn;
 	__u16 handle, flags;
+	int err;
 
 	hdr = skb_pull_data(skb, sizeof(*hdr));
 	if (!hdr) {
 		bt_dev_err(hdev, "ACL packet too small");
-		goto drop;
+		kfree_skb(skb);
+		return;
 	}
 
 	handle = __le16_to_cpu(hdr->handle);
@@ -3850,36 +3851,27 @@ static void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 
 	hdev->stat.acl_rx++;
 
-	hci_dev_lock(hdev);
-	conn = hci_conn_hash_lookup_handle(hdev, handle);
-	hci_dev_unlock(hdev);
-
-	if (conn) {
-		hci_conn_enter_active_mode(conn, BT_POWER_FORCE_ACTIVE_OFF);
-
-		/* Send to upper protocol */
-		l2cap_recv_acldata(conn, skb, flags);
-		return;
-	} else {
+	err = l2cap_recv_acldata(hdev, handle, skb, flags);
+	if (err == -ENOENT)
 		bt_dev_err(hdev, "ACL packet for unknown connection handle %d",
 			   handle);
-	}
-
-drop:
-	kfree_skb(skb);
+	else if (err)
+		bt_dev_dbg(hdev, "ACL packet recv for handle %d failed: %d",
+			   handle, err);
 }
 
 /* SCO data packet */
 static void hci_scodata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	struct hci_sco_hdr *hdr;
-	struct hci_conn *conn;
 	__u16 handle, flags;
+	int err;
 
 	hdr = skb_pull_data(skb, sizeof(*hdr));
 	if (!hdr) {
 		bt_dev_err(hdev, "SCO packet too small");
-		goto drop;
+		kfree_skb(skb);
+		return;
 	}
 
 	handle = __le16_to_cpu(hdr->handle);
@@ -3891,34 +3883,28 @@ static void hci_scodata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 
 	hdev->stat.sco_rx++;
 
-	hci_dev_lock(hdev);
-	conn = hci_conn_hash_lookup_handle(hdev, handle);
-	hci_dev_unlock(hdev);
+	hci_skb_pkt_status(skb) = flags & 0x03;
 
-	if (conn) {
-		/* Send to upper protocol */
-		hci_skb_pkt_status(skb) = flags & 0x03;
-		sco_recv_scodata(conn, skb);
-		return;
-	} else {
+	err = sco_recv_scodata(hdev, handle, skb);
+	if (err == -ENOENT)
 		bt_dev_err_ratelimited(hdev, "SCO packet for unknown connection handle %d",
 				       handle);
-	}
-
-drop:
-	kfree_skb(skb);
+	else if (err)
+		bt_dev_dbg(hdev, "SCO packet recv for handle %d failed: %d",
+			   handle, err);
 }
 
 static void hci_isodata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	struct hci_iso_hdr *hdr;
-	struct hci_conn *conn;
 	__u16 handle, flags;
+	int err;
 
 	hdr = skb_pull_data(skb, sizeof(*hdr));
 	if (!hdr) {
 		bt_dev_err(hdev, "ISO packet too small");
-		goto drop;
+		kfree_skb(skb);
+		return;
 	}
 
 	handle = __le16_to_cpu(hdr->handle);
@@ -3928,22 +3914,13 @@ static void hci_isodata_packet(struct hci_dev *hdev, struct sk_buff *skb)
 	bt_dev_dbg(hdev, "len %d handle 0x%4.4x flags 0x%4.4x", skb->len,
 		   handle, flags);
 
-	hci_dev_lock(hdev);
-	conn = hci_conn_hash_lookup_handle(hdev, handle);
-	hci_dev_unlock(hdev);
-
-	if (!conn) {
+	err = iso_recv(hdev, handle, skb, flags);
+	if (err == -ENOENT)
 		bt_dev_err(hdev, "ISO packet for unknown connection handle %d",
 			   handle);
-		goto drop;
-	}
-
-	/* Send to upper protocol */
-	iso_recv(conn, skb, flags);
-	return;
-
-drop:
-	kfree_skb(skb);
+	else if (err)
+		bt_dev_dbg(hdev, "ISO packet recv for handle %d failed: %d",
+			   handle, err);
 }
 
 static bool hci_req_is_complete(struct hci_dev *hdev)
@@ -4121,7 +4098,7 @@ static void hci_rx_work(struct work_struct *work)
 	}
 }
 
-static void hci_send_cmd_sync(struct hci_dev *hdev, struct sk_buff *skb)
+static int hci_send_cmd_sync(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	int err;
 
@@ -4133,16 +4110,19 @@ static void hci_send_cmd_sync(struct hci_dev *hdev, struct sk_buff *skb)
 	if (!hdev->sent_cmd) {
 		skb_queue_head(&hdev->cmd_q, skb);
 		queue_work(hdev->workqueue, &hdev->cmd_work);
-		return;
+		return -EINVAL;
 	}
 
 	if (hci_skb_opcode(skb) != HCI_OP_NOP) {
 		err = hci_send_frame(hdev, skb);
 		if (err < 0) {
 			hci_cmd_sync_cancel_sync(hdev, -err);
-			return;
+			return err;
 		}
 		atomic_dec(&hdev->cmd_cnt);
+	} else {
+		err = -ENODATA;
+		kfree_skb(skb);
 	}
 
 	if (hdev->req_status == HCI_REQ_PEND &&
@@ -4150,12 +4130,15 @@ static void hci_send_cmd_sync(struct hci_dev *hdev, struct sk_buff *skb)
 		kfree_skb(hdev->req_skb);
 		hdev->req_skb = skb_clone(hdev->sent_cmd, GFP_KERNEL);
 	}
+
+	return err;
 }
 
 static void hci_cmd_work(struct work_struct *work)
 {
 	struct hci_dev *hdev = container_of(work, struct hci_dev, cmd_work);
 	struct sk_buff *skb;
+	int err;
 
 	BT_DBG("%s cmd_cnt %d cmd queued %d", hdev->name,
 	       atomic_read(&hdev->cmd_cnt), skb_queue_len(&hdev->cmd_q));
@@ -4166,7 +4149,9 @@ static void hci_cmd_work(struct work_struct *work)
 		if (!skb)
 			return;
 
-		hci_send_cmd_sync(hdev, skb);
+		err = hci_send_cmd_sync(hdev, skb);
+		if (err)
+			return;
 
 		rcu_read_lock();
 		if (test_bit(HCI_RESET, &hdev->flags) ||

net/bluetooth/hci_sock.c

@@ -1311,7 +1311,9 @@ static int hci_sock_bind(struct socket *sock, struct sockaddr *addr,
 			goto done;
 		}
 
+		hci_dev_lock(hdev);
 		mgmt_index_removed(hdev);
+		hci_dev_unlock(hdev);
 
 		err = hci_dev_open(hdev->id);
 		if (err) {

net/bluetooth/iso.c

@@ -2314,14 +2314,31 @@ static void iso_disconn_cfm(struct hci_conn *hcon, __u8 reason)
 	iso_conn_del(hcon, bt_to_errno(reason));
 }
 
-void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
+int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 {
-	struct iso_conn *conn = hcon->iso_data;
+	struct hci_conn *hcon;
+	struct iso_conn *conn;
 	struct skb_shared_hwtstamps *hwts;
 	__u16 pb, ts, len, sn;
 
-	if (!conn)
-		goto drop;
+	hci_dev_lock(hdev);
+
+	hcon = hci_conn_hash_lookup_handle(hdev, handle);
+	if (!hcon) {
+		hci_dev_unlock(hdev);
+		kfree_skb(skb);
+		return -ENOENT;
+	}
+
+	conn = iso_conn_hold_unless_zero(hcon->iso_data);
+	hcon = NULL;
+
+	hci_dev_unlock(hdev);
+
+	if (!conn) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
 
 	pb     = hci_iso_flags_pb(flags);
 	ts     = hci_iso_flags_ts(flags);
@@ -2377,7 +2394,7 @@ void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 			hci_skb_pkt_status(skb) = flags & 0x03;
 			hci_skb_pkt_seqnum(skb) = sn;
 			iso_recv_frame(conn, skb);
-			return;
+			goto done;
 		}
 
 		if (pb == ISO_SINGLE) {
@@ -2455,6 +2472,9 @@ void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 
 drop:
 	kfree_skb(skb);
+done:
+	iso_conn_put(conn);
+	return 0;
 }
 
 static struct hci_cb iso_cb = {

net/bluetooth/l2cap_core.c

@@ -7510,13 +7510,24 @@ struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *c)
 	return c;
 }
 
-void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
+int l2cap_recv_acldata(struct hci_dev *hdev, u16 handle,
+		       struct sk_buff *skb, u16 flags)
 {
+	struct hci_conn *hcon;
 	struct l2cap_conn *conn;
 	int len;
 
-	/* Lock hdev to access l2cap_data to avoid race with l2cap_conn_del */
-	hci_dev_lock(hcon->hdev);
+	/* Lock hdev for hci_conn, and race on l2cap_data vs. l2cap_conn_del */
+	hci_dev_lock(hdev);
+
+	hcon = hci_conn_hash_lookup_handle(hdev, handle);
+	if (!hcon) {
+		hci_dev_unlock(hdev);
+		kfree_skb(skb);
+		return -ENOENT;
+	}
+
+	hci_conn_enter_active_mode(hcon, BT_POWER_FORCE_ACTIVE_OFF);
 
 	conn = hcon->l2cap_data;
 
@@ -7524,12 +7535,13 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
 		conn = l2cap_conn_add(hcon);
 
 	conn = l2cap_conn_hold_unless_zero(conn);
+	hcon = NULL;
 
-	hci_dev_unlock(hcon->hdev);
+	hci_dev_unlock(hdev);
 
 	if (!conn) {
 		kfree_skb(skb);
-		return;
+		return -EINVAL;
 	}
 
 	BT_DBG("conn %p len %u flags 0x%x", conn, skb->len, flags);
@@ -7643,6 +7655,7 @@ drop:
 unlock:
 	mutex_unlock(&conn->lock);
 	l2cap_conn_put(conn);
+	return 0;
 }
 
 static struct hci_cb l2cap_cb = {

net/bluetooth/sco.c

@@ -1458,22 +1458,39 @@ static void sco_disconn_cfm(struct hci_conn *hcon, __u8 reason)
 	sco_conn_del(hcon, bt_to_errno(reason));
 }
 
-void sco_recv_scodata(struct hci_conn *hcon, struct sk_buff *skb)
+int sco_recv_scodata(struct hci_dev *hdev, u16 handle, struct sk_buff *skb)
 {
-	struct sco_conn *conn = hcon->sco_data;
+	struct hci_conn *hcon;
+	struct sco_conn *conn;
 
-	if (!conn)
-		goto drop;
+	hci_dev_lock(hdev);
+
+	hcon = hci_conn_hash_lookup_handle(hdev, handle);
+	if (!hcon) {
+		hci_dev_unlock(hdev);
+		kfree_skb(skb);
+		return -ENOENT;
+	}
+
+	conn = sco_conn_hold_unless_zero(hcon->sco_data);
+	hcon = NULL;
+
+	hci_dev_unlock(hdev);
+
+	if (!conn) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
 
 	BT_DBG("conn %p len %u", conn, skb->len);
 
-	if (skb->len) {
+	if (skb->len)
 		sco_recv_frame(conn, skb);
-		return;
-	}
+	else
+		kfree_skb(skb);
 
-drop:
-	kfree_skb(skb);
+	sco_conn_put(conn);
+	return 0;
 }
 
 static struct hci_cb sco_cb = {

net/bluetooth/smp.c

@@ -2136,7 +2136,7 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
 	struct smp_chan *smp = chan->data;
 	struct hci_conn *hcon = conn->hcon;
 	u8 *pkax, *pkbx, *na, *nb, confirm_hint;
-	u32 passkey;
+	u32 passkey = 0;
 	int err;
 
 	bt_dev_dbg(hcon->hdev, "conn %p", conn);
@@ -2188,24 +2188,6 @@ static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
 		smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd),
 			     smp->prnd);
 		SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK);
-
-		/* Only Just-Works pairing requires extra checks */
-		if (smp->method != JUST_WORKS)
-			goto mackey_and_ltk;
-
-		/* If there already exists long term key in local host, leave
-		 * the decision to user space since the remote device could
-		 * be legitimate or malicious.
-		 */
-		if (hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
-				 hcon->role)) {
-			/* Set passkey to 0. The value can be any number since
-			 * it'll be ignored anyway.
-			 */
-			passkey = 0;
-			confirm_hint = 1;
-			goto confirm;
-		}
 	}
 
 mackey_and_ltk:
@@ -2226,11 +2208,12 @@ mackey_and_ltk:
 	if (err)
 		return SMP_UNSPECIFIED;
 
-	confirm_hint = 0;
-
-confirm:
-	if (smp->method == JUST_WORKS)
-		confirm_hint = 1;
+	/* Always require user confirmation for Just-Works pairing to prevent
+	 * impersonation attacks, or in case of a legitimate device that is
+	 * repairing use the confirmation as acknowledgment to proceed with the
+	 * creation of new keys.
+	 */
+	confirm_hint = smp->method == JUST_WORKS ? 1 : 0;
 
 	err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type,
 					hcon->dst_type, passkey, confirm_hint);