Bluetooth: Fix trying LTK re-encryption when we don't have an LTK

In the case that the key distribution bits cause us not to generate a
local LTK we should not try to re-encrypt if we're currently encrypted
with an STK. This patch fixes the check for this in the
smp_sufficient_security function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index bf3568c46847..8339d6b0f2b8 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -876,9 +876,12 @@ bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level)
         /* If we're encrypted with an STK always claim insufficient
          * security. This way we allow the connection to be re-encrypted
          * with an LTK, even if the LTK provides the same level of
-         * security.
+         * security. Only exception is if we don't have an LTK (e.g.
+         * because of key distribution bits).
          */
-        if (test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags))
+        if (test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) &&
+            hci_find_ltk_by_addr(hcon->hdev, &hcon->dst, hcon->dst_type,
+                                 hcon->out))
                 return false;
 
         if (hcon->sec_level >= sec_level)