Bluetooth: Fix overriding higher security level in SMP
When we receive a pairing request or an internal request to start
pairing we shouldn't blindly overwrite the existing pending_sec_level
value as that may actually be higher than the new one. This patch fixes
the SMP code to only overwrite the value in case the new one is higher
than the old.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index f2829a7..0189ec8 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -669,7 +669,7 @@
{
struct smp_cmd_pairing rsp, *req = (void *) skb->data;
struct smp_chan *smp;
- u8 key_size, auth;
+ u8 key_size, auth, sec_level;
int ret;
BT_DBG("conn %p", conn);
@@ -695,7 +695,9 @@
/* We didn't start the pairing, so match remote */
auth = req->auth_req;
- conn->hcon->pending_sec_level = authreq_to_seclevel(auth);
+ sec_level = authreq_to_seclevel(auth);
+ if (sec_level > conn->hcon->pending_sec_level)
+ conn->hcon->pending_sec_level = sec_level;
build_pairing_cmd(conn, req, &rsp, auth);
@@ -838,6 +840,7 @@
struct smp_cmd_pairing cp;
struct hci_conn *hcon = conn->hcon;
struct smp_chan *smp;
+ u8 sec_level;
BT_DBG("conn %p", conn);
@@ -847,7 +850,9 @@
if (!(conn->hcon->link_mode & HCI_LM_MASTER))
return SMP_CMD_NOTSUPP;
- hcon->pending_sec_level = authreq_to_seclevel(rp->auth_req);
+ sec_level = authreq_to_seclevel(rp->auth_req);
+ if (sec_level > hcon->pending_sec_level)
+ hcon->pending_sec_level = sec_level;
if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
return 0;
@@ -901,9 +906,12 @@
if (smp_sufficient_security(hcon, sec_level))
return 1;
+ if (sec_level > hcon->pending_sec_level)
+ hcon->pending_sec_level = sec_level;
+
if (hcon->link_mode & HCI_LM_MASTER)
- if (smp_ltk_encrypt(conn, sec_level))
- goto done;
+ if (smp_ltk_encrypt(conn, hcon->pending_sec_level))
+ return 0;
if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags))
return 0;
@@ -918,7 +926,7 @@
* requires it.
*/
if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT ||
- sec_level > BT_SECURITY_MEDIUM)
+ hcon->pending_sec_level > BT_SECURITY_MEDIUM)
authreq |= SMP_AUTH_MITM;
if (hcon->link_mode & HCI_LM_MASTER) {
@@ -937,9 +945,6 @@
set_bit(SMP_FLAG_INITIATOR, &smp->flags);
-done:
- hcon->pending_sec_level = sec_level;
-
return 0;
}