From 49cd6fbccf0414950b03555bb2efbb0c4dc163c0 Mon Sep 17 00:00:00 2001
From: Cyrill Gorcunov <gorcunov@gmail.com>
Date: Mon, 6 Sep 2010 23:49:52 +0400
Subject: Fix NULL dereferences on %substr missing operands

%substr with dangling id issues SIGSEV. Fix it.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
---
 preproc.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/preproc.c b/preproc.c
index e3b0c640..22d30ca9 100644
--- a/preproc.c
+++ b/preproc.c
@@ -3395,12 +3395,13 @@ issue_error:
         tline = expand_smacro(tline->next);
         last->next = NULL;
 
-        t = tline->next;
+        if (tline) /* skip expanded id */
+            t = tline->next;
         while (tok_type_(t, TOK_WHITESPACE))
             t = t->next;
 
         /* t should now point to the string */
-        if (t->type != TOK_STRING) {
+        if (!tok_type_(t, TOK_STRING)) {
             error(ERR_NONFATAL,
                   "`%%substr` requires string as second parameter");
             free_tlist(tline);
-- 
cgit v1.2.1