From e90b5803bf300778b76f0dbe7a0592eb86163304 Mon Sep 17 00:00:00 2001
From: XANTRONIX Development <dev@xantronix.com>
Date: Fri, 24 Jul 2020 19:48:22 -0400
Subject: [PATCH] Add validation to patty_ax25_sock_send_xid()

Changes:

    * Make patty_ax25_sock_send_xid() set ENETDOWN when no network
      interface is associated with a sock
---
 src/sock.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/sock.c b/src/sock.c
index a60c406..0351dfc 100644
--- a/src/sock.c
+++ b/src/sock.c
@@ -529,8 +529,10 @@ ssize_t patty_ax25_sock_send_xid(patty_ax25_sock *sock,
 
     ssize_t encoded;
 
-    if (sock->remote.callsign[0] == '\0') {
-        goto error_nopeer;
+    if (sock->iface == NULL) {
+        errno = ENETDOWN;
+
+        goto error_noif;
     }
 
     params.flags = (1 << PATTY_AX25_PARAM_CLASSES)
@@ -558,7 +560,7 @@ ssize_t patty_ax25_sock_send_xid(patty_ax25_sock *sock,
                                 encoded);
 
 error_frame_encode_xid:
-error_nopeer:
+error_noif:
     return -1;
 }