From: Florian Westphal <fw@strlen.de>
Date: Mon, 4 Mar 2019 00:06:05 +0000 (+0100)
Subject: segtree: fix crash when debug mode is active
X-Git-Tag: v0.9.1~133
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=afd1ad6f68680c0f0a4afad7c67ddc8652948732;p=thirdparty%2Fnftables.git

segtree: fix crash when debug mode is active

We must set output_fp to sensible filep, else crash.

Reported-by: Václav Zindulka <vaclav.zindulka@tlapnet.cz>
Signed-off-by: Florian Westphal <fw@strlen.de>
---

diff --git a/src/segtree.c b/src/segtree.c
index e5dfd413..e3a2f48c 100644
--- a/src/segtree.c
+++ b/src/segtree.c
@@ -9,6 +9,7 @@
  */
 
 #include <stdlib.h>
+#include <string.h>
 #include <inttypes.h>
 #include <arpa/inet.h>
 
@@ -67,8 +68,6 @@ struct elementary_interval {
 	struct expr			*expr;
 };
 
-static struct output_ctx debug_octx = {};
-
 static void seg_tree_init(struct seg_tree *tree, const struct set *set,
 			  struct expr *init, unsigned int debug_mask)
 {
@@ -570,6 +569,7 @@ int set_to_intervals(struct list_head *errs, struct set *set,
 		     bool merge)
 {
 	struct elementary_interval *ei, *next;
+	struct output_ctx debug_octx;
 	struct seg_tree tree;
 	LIST_HEAD(list);
 
@@ -590,6 +590,9 @@ int set_to_intervals(struct list_head *errs, struct set *set,
 	}
 
 	if (segtree_debug(tree.debug_mask)) {
+		memset(&debug_octx, 0, sizeof(debug_octx));
+		debug_octx.output_fp = stderr;
+		debug_octx.error_fp = stderr;
 		expr_print(init, &debug_octx);
 		pr_gmp_debug("\n");
 	}