Avoid potential crash in close of a verify callout

diff --git a/src/src/verify.c b/src/src/verify.c
index 720f85d8ce7f537539bde311acdd7ab6bb60937c..184809fb55ab434f3e6d4387bc106f6832659258 100644 (file)
--- a/src/src/verify.c
+++ b/src/src/verify.c
@@ -1103,12 +1103,9 @@ no_conn:
       if (options & vopt_callout_recipsender)
         cancel_cutthrough_connection(TRUE, US"not usable for cutthrough");
       if (sx.send_quit)
-       {
-       (void) smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n");
-
-       /* Wait a short time for response, and discard it */
-       smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2', 1);
-       }
+       if (smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n") != -1)
+         /* Wait a short time for response, and discard it */
+         smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2', 1);
 
       if (sx.cctx.sock >= 0)
        {