[Bluetooth] Disconnect when encryption gets disabled

The Bluetooth specification allows to enable or disable the encryption
of an ACL link at any time by either the peer or the remote device. If
a L2CAP or RFCOMM connection requested an encrypted link, they will now
disconnect that link if the encryption gets disabled. Higher protocols
that don't care about encryption (like SDP) are not affected.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index 1f92f9ab4959..e7a6a03cea37 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -2003,6 +2003,14 @@ static void rfcomm_encrypt_cfm(struct hci_conn *conn, u8 status, u8 encrypt)
         list_for_each_safe(p, n, &s->dlcs) {
                 d = list_entry(p, struct rfcomm_dlc, list);
 
+                if ((d->link_mode & (RFCOMM_LM_ENCRYPT | RFCOMM_LM_SECURE)) &&
+                                        (d->state == BT_CONNECTED ||
+                                                d->state == BT_CONFIG) &&
+                                                !status && encrypt == 0x00) {
+                        __rfcomm_dlc_close(d, ECONNREFUSED);
+                        continue;
+                }
+
                 if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))
                         continue;