Bluetooth: Correct packet len calculation
Andrei Emeltchenko [Fri, 30 Dec 2011 10:07:47 +0000 (12:07 +0200)]
Remove unneeded skb_pull and correct packet length calculation
removing magic number. Move BT_DBG after len check otherwise
it could possibly access wrong memory.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/hci_event.c

index 08c0b42..d37f5b2 100644 (file)
@@ -2271,20 +2271,19 @@ static inline void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct sk_buff *s
        struct hci_ev_num_comp_pkts *ev = (void *) skb->data;
        int i;
 
-       skb_pull(skb, sizeof(*ev));
-
-       BT_DBG("%s num_hndl %d", hdev->name, ev->num_hndl);
-
        if (hdev->flow_ctl_mode != HCI_FLOW_CTL_MODE_PACKET_BASED) {
                BT_ERR("Wrong event for mode %d", hdev->flow_ctl_mode);
                return;
        }
 
-       if (skb->len < ev->num_hndl * 4) {
+       if (skb->len < sizeof(*ev) || skb->len < sizeof(*ev) +
+                       ev->num_hndl * sizeof(struct hci_comp_pkts_info)) {
                BT_DBG("%s bad parameters", hdev->name);
                return;
        }
 
+       BT_DBG("%s num_hndl %d", hdev->name, ev->num_hndl);
+
        for (i = 0; i < ev->num_hndl; i++) {
                struct hci_comp_pkts_info *info = &ev->handles[i];
                struct hci_conn *conn;