From: Luiz Augusto von Dentz Date: Fri, 10 Apr 2026 19:29:52 +0000 (-0400) Subject: Bluetooth: hci_event: Fix OOB read and infinite loop in hci_le_create_big_complete_evt X-Git-Tag: v7.1-rc3~26^2~21^2~17 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5ddb8014261137cadaf83ab5617a588d80a22586;p=thirdparty%2Flinux.git Bluetooth: hci_event: Fix OOB read and infinite loop in hci_le_create_big_complete_evt hci_le_create_big_complete_evt() iterates over BT_BOUND connections for a BIG handle using a while loop, accessing ev->bis_handle[i++] on each iteration. However, there is no check that i stays within ev->num_bis before the array access. When a controller sends a LE_Create_BIG_Complete event with fewer bis_handle entries than there are BT_BOUND connections for that BIG, or with num_bis=0, the loop reads beyond the valid bis_handle[] flex array into adjacent heap memory. Since the out-of-bounds values typically exceed HCI_CONN_HANDLE_MAX (0x0EFF), hci_conn_set_handle() rejects them and the connection remains in BT_BOUND state. The same connection is then found again by hci_conn_hash_lookup_big_state(), creating an infinite loop with hci_dev_lock held. Fix this by terminating the BIG if in case not all BIS could be setup properly. Fixes: a0bfde167b50 ("Bluetooth: ISO: Add support for connecting multiple BISes") Cc: stable@vger.kernel.org Signed-off-by: ZhiTao Ou Signed-off-by: Luiz Augusto von Dentz --- diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index b2ee6b6a0f56..1b3b9131affa 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -7118,9 +7118,29 @@ static void hci_le_create_big_complete_evt(struct hci_dev *hdev, void *data, continue; } + if (ev->num_bis <= i) { + bt_dev_err(hdev, + "Not enough BIS handles for BIG 0x%2.2x", + ev->handle); + ev->status = HCI_ERROR_UNSPECIFIED; + hci_connect_cfm(conn, ev->status); + hci_conn_del(conn); + continue; + } + if (hci_conn_set_handle(conn, - __le16_to_cpu(ev->bis_handle[i++]))) + __le16_to_cpu(ev->bis_handle[i++]))) { + bt_dev_err(hdev, + "Failed to set BIS handle for BIG 0x%2.2x", + ev->handle); + /* Force error so BIG gets terminated as not all BIS + * could be connected. + */ + ev->status = HCI_ERROR_UNSPECIFIED; + hci_connect_cfm(conn, ev->status); + hci_conn_del(conn); continue; + } conn->state = BT_CONNECTED; set_bit(HCI_CONN_BIG_CREATED, &conn->flags); @@ -7129,7 +7149,10 @@ static void hci_le_create_big_complete_evt(struct hci_dev *hdev, void *data, hci_iso_setup_path(conn); } - if (!ev->status && !i) + /* If there is an unexpected error or if no BISes have been connected + * for the BIG, terminate it. + */ + if (ev->status == HCI_ERROR_UNSPECIFIED || (!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