Bluetooth: Fix the creation of hdev->name

commit 103a2f3255a95991252f8f13375c3a96a75011cd upstream.

Set a size limit of 8 bytes of the written buffer to "hdev->name"
including the terminating null byte, as the size of "hdev->name" is 8
bytes. If an id value which is greater than 9999 is allocated,
then the "snprintf(hdev->name, sizeof(hdev->name), "hci%d", id)"
function call would lead to a truncation of the id value in decimal
notation.

Set an explicit maximum id parameter in the id allocation function call.
The id allocation function defines the maximum allocated id value as the
maximum id parameter value minus one. Therefore, HCI_MAX_ID is defined
as 10000.

Signed-off-by: Itay Iellin <ieitayie@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 51afaaa684087308c974c6449f4fcdb70db72cb0..d42288a06af6188aa7c12dc219d5805648d3bb7f 100644 (file)
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -34,6 +34,9 @@
 /* HCI priority */
 #define HCI_PRIO_MAX   7
 
+/* HCI maximum id value */
+#define HCI_MAX_ID 10000
+
 /* HCI Core structures */
 struct inquiry_data {
        bdaddr_t        bdaddr;

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 687b4d0e4c6730801f6bdfa55ab33ae98af55ead..a6f186a04fe70234aa966b0e9ded24e69add35a0 100644 (file)
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3100,10 +3100,10 @@ int hci_register_dev(struct hci_dev *hdev)
         */
        switch (hdev->dev_type) {
        case HCI_PRIMARY:
-               id = ida_simple_get(&hci_index_ida, 0, 0, GFP_KERNEL);
+               id = ida_simple_get(&hci_index_ida, 0, HCI_MAX_ID, GFP_KERNEL);
                break;
        case HCI_AMP:
-               id = ida_simple_get(&hci_index_ida, 1, 0, GFP_KERNEL);
+               id = ida_simple_get(&hci_index_ida, 1, HCI_MAX_ID, GFP_KERNEL);
                break;
        default:
                return -EINVAL;
@@ -3112,7 +3112,7 @@ int hci_register_dev(struct hci_dev *hdev)
        if (id < 0)
                return id;
 
-       sprintf(hdev->name, "hci%d", id);
+       snprintf(hdev->name, sizeof(hdev->name), "hci%d", id);
        hdev->id = id;
 
        BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus);