wpaspy: Do not mark not-existing UNIX domain socket as UDP

os.stat(path) failure is an ambigious indication of the control
interface "path" type (UDP hostname vs. UNIX domain socket path). The
path may be a valid UNIX domain socket path, but that socket could have
been removed just before reaching here. At least the hwsim test case
concurrent_p2pcli managed to hit the "connect exception" print below
from UDP handling even when using a UNIX domain socket.

Work around incorrect determination of control interface socket type by
assuming anything starting with '/' is a UNIX domain socket and not a
hostname.

Fixes: a2c88a8025 ("wpaspy: Add support for UDP connection")
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>

wpaspy/wpaspy.py

@@ -21,14 +21,14 @@ class Ctrl:
         self.path = path
         self.port = port
 
-        try:
-            mode = os.stat(path).st_mode
-            if stat.S_ISSOCK(mode):
-                self.udp = False
-            else:
+        self.udp = False
+        if not path.startswith('/'):
+            try:
+                mode = os.stat(path).st_mode
+                if not stat.S_ISSOCK(mode):
+                    self.udp = True
+            except:
                 self.udp = True
-        except:
-            self.udp = True
 
         if not self.udp:
             self.s = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)