Merge tag 'for-net-2023-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth

Luiz Augusto von Dentz says:

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

 - Fix race when opening vhci device
 - Avoid memcmp() out of bounds warning
 - Correctly bounds check and pad HCI_MON_NEW_INDEX name
 - Fix using memcmp when comparing keys
 - Ignore error return for hci_devcd_register() in btrtl
 - Always check if connection is alive before deleting
 - Fix a refcnt underflow problem for hci_conn

* tag 'for-net-2023-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth:
  Bluetooth: hci_sock: Correctly bounds check and pad HCI_MON_NEW_INDEX name
  Bluetooth: avoid memcmp() out of bounds warning
  Bluetooth: hci_sock: fix slab oob read in create_monitor_event
  Bluetooth: btrtl: Ignore error return for hci_devcd_register()
  Bluetooth: hci_event: Fix coding style
  Bluetooth: hci_event: Fix using memcmp when comparing keys
  Bluetooth: Fix a refcnt underflow problem for hci_conn
  Bluetooth: hci_sync: always check if connection is alive before deleting
  Bluetooth: Reject connection with the device which has same BD_ADDR
  Bluetooth: hci_event: Ignore NULL link key
  Bluetooth: ISO: Fix invalid context error
  Bluetooth: vhci: Fix race when opening vhci device
====================

Link: https://lore.kernel.org/r/20231014031336.1664558-1-luiz.dentz@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

4 files changed, 62 insertions, 24 deletions

diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
index 7a6f20338db8..73470cc3518a 100644
--- a/net/bluetooth/hci_conn.c
+++ b/net/bluetooth/hci_conn.c
@@ -1627,6 +1627,15 @@ struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
 		return ERR_PTR(-EOPNOTSUPP);
 	}
 
+	/* Reject outgoing connection to device with same BD ADDR against
+	 * CVE-2020-26555
+	 */
+	if (!bacmp(&hdev->bdaddr, dst)) {
+		bt_dev_dbg(hdev, "Reject connection with same BD_ADDR %pMR\n",
+			   dst);
+		return ERR_PTR(-ECONNREFUSED);
+	}
+
 	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
 	if (!acl) {
 		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 31d02b54eea1..1e1c9147356c 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -26,6 +26,8 @@
 /* Bluetooth HCI event handling. */
 
 #include <asm/unaligned.h>
+#include <linux/crypto.h>
+#include <crypto/algapi.h>
 
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
@@ -3268,6 +3270,16 @@ static void hci_conn_request_evt(struct hci_dev *hdev, void *data,
 
 	bt_dev_dbg(hdev, "bdaddr %pMR type 0x%x", &ev->bdaddr, ev->link_type);
 
+	/* Reject incoming connection from device with same BD ADDR against
+	 * CVE-2020-26555
+	 */
+	if (hdev && !bacmp(&hdev->bdaddr, &ev->bdaddr)) {
+		bt_dev_dbg(hdev, "Reject connection with same BD_ADDR %pMR\n",
+			   &ev->bdaddr);
+		hci_reject_conn(hdev, &ev->bdaddr);
+		return;
+	}
+
 	mask |= hci_proto_connect_ind(hdev, &ev->bdaddr, ev->link_type,
 				      &flags);
 
@@ -4742,6 +4754,15 @@ static void hci_link_key_notify_evt(struct hci_dev *hdev, void *data,
 	if (!conn)
 		goto unlock;
 
+	/* Ignore NULL link key against CVE-2020-26555 */
+	if (!crypto_memneq(ev->link_key, ZERO_KEY, HCI_LINK_KEY_SIZE)) {
+		bt_dev_dbg(hdev, "Ignore NULL link key (ZERO KEY) for %pMR",
+			   &ev->bdaddr);
+		hci_disconnect(conn, HCI_ERROR_AUTH_FAILURE);
+		hci_conn_drop(conn);
+		goto unlock;
+	}
+
 	hci_conn_hold(conn);
 	conn->disc_timeout = HCI_DISCONN_TIMEOUT;
 	hci_conn_drop(conn);
@@ -5274,8 +5295,8 @@ static u8 bredr_oob_data_present(struct hci_conn *conn)
 		 * available, then do not declare that OOB data is
 		 * present.
 		 */
-		if (!memcmp(data->rand256, ZERO_KEY, 16) ||
-		    !memcmp(data->hash256, ZERO_KEY, 16))
+		if (!crypto_memneq(data->rand256, ZERO_KEY, 16) ||
+		    !crypto_memneq(data->hash256, ZERO_KEY, 16))
 			return 0x00;
 
 		return 0x02;
@@ -5285,8 +5306,8 @@ static u8 bredr_oob_data_present(struct hci_conn *conn)
 	 * not supported by the hardware, then check that if
 	 * P-192 data values are present.
 	 */
-	if (!memcmp(data->rand192, ZERO_KEY, 16) ||
-	    !memcmp(data->hash192, ZERO_KEY, 16))
+	if (!crypto_memneq(data->rand192, ZERO_KEY, 16) ||
+	    !crypto_memneq(data->hash192, ZERO_KEY, 16))
 		return 0x00;
 
 	return 0x01;
@@ -5303,7 +5324,7 @@ static void hci_io_capa_request_evt(struct hci_dev *hdev, void *data,
 	hci_dev_lock(hdev);
 
 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &ev->bdaddr);
-	if (!conn)
+	if (!conn || !hci_conn_ssp_enabled(conn))
 		goto unlock;
 
 	hci_conn_hold(conn);
@@ -5550,7 +5571,7 @@ static void hci_simple_pair_complete_evt(struct hci_dev *hdev, void *data,
 	hci_dev_lock(hdev);
 
 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &ev->bdaddr);
-	if (!conn)
+	if (!conn || !hci_conn_ssp_enabled(conn))
 		goto unlock;
 
 	/* Reset the authentication requirement to unknown */
@@ -7021,6 +7042,14 @@ unlock:
 	hci_dev_unlock(hdev);
 }
 
+static int hci_iso_term_big_sync(struct hci_dev *hdev, void *data)
+{
+	u8 handle = PTR_UINT(data);
+
+	return hci_le_terminate_big_sync(hdev, handle,
+					 HCI_ERROR_LOCAL_HOST_TERM);
+}
+
 static void hci_le_create_big_complete_evt(struct hci_dev *hdev, void *data,
 					   struct sk_buff *skb)
 {
@@ -7065,16 +7094,17 @@ static void hci_le_create_big_complete_evt(struct hci_dev *hdev, void *data,
 		rcu_read_lock();
 	}
 
+	rcu_read_unlock();
+
 	if (!ev->status && !i)
 		/* If no BISes have been connected for the BIG,
 		 * terminate. This is in case all bound connections
 		 * have been closed before the BIG creation
 		 * has completed.
 		 */
-		hci_le_terminate_big_sync(hdev, ev->handle,
-					  HCI_ERROR_LOCAL_HOST_TERM);
+		hci_cmd_sync_queue(hdev, hci_iso_term_big_sync,
+				   UINT_PTR(ev->handle), NULL);
 
-	rcu_read_unlock();
 	hci_dev_unlock(hdev);
 }
 
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 5e4f718073b7..3e7cd330d731 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -488,7 +488,8 @@ static struct sk_buff *create_monitor_event(struct hci_dev *hdev, int event)
 		ni->type = hdev->dev_type;
 		ni->bus = hdev->bus;
 		bacpy(&ni->bdaddr, &hdev->bdaddr);
-		memcpy(ni->name, hdev->name, 8);
+		memcpy_and_pad(ni->name, sizeof(ni->name), hdev->name,
+			       strnlen(hdev->name, sizeof(ni->name)), '\0');
 
 		opcode = cpu_to_le16(HCI_MON_NEW_INDEX);
 		break;
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index d06e07a0ea5a..a15ab0b874a9 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -5369,6 +5369,7 @@ int hci_abort_conn_sync(struct hci_dev *hdev, struct hci_conn *conn, u8 reason)
 {
 	int err = 0;
 	u16 handle = conn->handle;
+	bool disconnect = false;
 	struct hci_conn *c;
 
 	switch (conn->state) {
@@ -5399,24 +5400,15 @@ int hci_abort_conn_sync(struct hci_dev *hdev, struct hci_conn *conn, u8 reason)
 		hci_dev_unlock(hdev);
 		return 0;
 	case BT_BOUND:
-		hci_dev_lock(hdev);
-		hci_conn_failed(conn, reason);
-		hci_dev_unlock(hdev);
-		return 0;
+		break;
 	default:
-		hci_dev_lock(hdev);
-		conn->state = BT_CLOSED;
-		hci_disconn_cfm(conn, reason);
-		hci_conn_del(conn);
-		hci_dev_unlock(hdev);
-		return 0;
+		disconnect = true;
+		break;
 	}
 
 	hci_dev_lock(hdev);
 
-	/* Check if the connection hasn't been cleanup while waiting
-	 * commands to complete.
-	 */
+	/* Check if the connection has been cleaned up concurrently */
 	c = hci_conn_hash_lookup_handle(hdev, handle);
 	if (!c || c != conn) {
 		err = 0;
@@ -5428,7 +5420,13 @@ int hci_abort_conn_sync(struct hci_dev *hdev, struct hci_conn *conn, u8 reason)
 	 * or in case of LE it was still scanning so it can be cleanup
 	 * safely.
 	 */
-	hci_conn_failed(conn, reason);
+	if (disconnect) {
+		conn->state = BT_CLOSED;
+		hci_disconn_cfm(conn, reason);
+		hci_conn_del(conn);
+	} else {
+		hci_conn_failed(conn, reason);
+	}
 
 unlock:
 	hci_dev_unlock(hdev);