Fixes for issues reported by Coverity (VPP-972)

Change-Id: I25238debb7081b4467aec4620dfdef33fbef3295
Signed-off-by: Chris Luke <chrisy@flirble.org>
diff --git a/src/vppinfra/socket.c b/src/vppinfra/socket.c
index 7ade440..37dcbbf 100644
--- a/src/vppinfra/socket.c
+++ b/src/vppinfra/socket.c
@@ -359,9 +359,21 @@
 	  && s->flags & SOCKET_ALLOW_GROUP_WRITE)
 	{
 	  struct stat st = { 0 };
-	  stat (((struct sockaddr_un *) &addr)->sun_path, &st);
+	  if (stat (((struct sockaddr_un *) &addr)->sun_path, &st) < 0)
+	    {
+	      error = clib_error_return_unix (0, "stat (fd %d, '%s')",
+					      s->fd, s->config);
+	      goto done;
+	    }
 	  st.st_mode |= S_IWGRP;
-	  chmod (((struct sockaddr_un *) &addr)->sun_path, st.st_mode);
+	  if (chmod (((struct sockaddr_un *) &addr)->sun_path, st.st_mode) <
+	      0)
+	    {
+	      error =
+		clib_error_return_unix (0, "chmod (fd %d, '%s', mode %o)",
+					s->fd, s->config, st.st_mode);
+	      goto done;
+	    }
 	}
     }
   else