Return-Path: Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 8.1 \(1993\)) Subject: Re: [PATCH] bluetooth: Fix possible NULL dereference From: Marcel Holtmann In-Reply-To: <1417592765-24836-1-git-send-email-Andrei.Emeltchenko.news@gmail.com> Date: Wed, 3 Dec 2014 08:00:00 +0000 Cc: linux-bluetooth@vger.kernel.org Message-Id: <1CCB1571-FD46-4F46-9106-2FAD1ABB3960@holtmann.org> References: <1417592765-24836-1-git-send-email-Andrei.Emeltchenko.news@gmail.com> To: Andrei Emeltchenko Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Andrei, > conn might be NULL and would be dereferenced in conn_set_key() > --- > net/bluetooth/hci_event.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c > index bd0a801..95f8057 100644 > --- a/net/bluetooth/hci_event.c > +++ b/net/bluetooth/hci_event.c > @@ -3312,7 +3312,7 @@ static void hci_link_key_notify_evt(struct hci_dev *hdev, struct sk_buff *skb) > /* Update connection information since adding the key will have > * fixed up the type in the case of changed combination keys. > */ > - if (ev->key_type == HCI_LK_CHANGED_COMBINATION) > + if (conn && ev->key_type == HCI_LK_CHANGED_COMBINATION) > conn_set_key(conn, key->type, key->pin_len); > > mgmt_new_link_key(hdev, key, persistent); the more important question is why we are considering link keys from the controller for a device that we do not have a hci_conn object for. If this is for security mode 3, then we should handle security mode 3 and then bail out of this function. Since security mode 3 means that we never get SSP or SC based keys. It is legacy pairing and does not need any special handling for debug keys or changed combination keys. Regards Marcel