[nrf fromtree] Bluetooth: Mesh: fix memory corruption if oob string i...

s 16 bytes

strcpy copies string including terminating null character.
strlen returns length without terminating null symbol.
If oob string is 16 bytes length then strcpy will corrupt byte
after auth array.

Signed-off-by: Aleksandr Khromykh <[email protected]>
(cherry picked from commit 7e63139)

Author: alxelax

subsys/bluetooth/mesh/prov.c

@@ -313,7 +313,7 @@ int bt_mesh_input_string(const char *str)
 		return -EINVAL;
 	}
 
-	strcpy((char *)bt_mesh_prov_link.auth, str);
+	memcpy(bt_mesh_prov_link.auth, str, strlen(str));
 
 	bt_mesh_prov_link.role->input_complete();