From: Roy Marples <roy@marples.name>
Date: Tue, 30 Jul 2019 10:04:24 +0000 (+0100)
Subject: routes: Fix a NULL dereference error for global static routes
X-Git-Tag: v8.0.2^0
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=aaa0ed852d6f1e9e17b0cf7ce985bd5cb130c999;p=thirdparty%2Fdhcpcd.git

routes: Fix a NULL dereference error for global static routes

No idea why you would want them, but just in case .....
---

diff --git a/src/dhcpcd.c b/src/dhcpcd.c
index ac498a62..5b64abf4 100644
--- a/src/dhcpcd.c
+++ b/src/dhcpcd.c
@@ -2125,13 +2125,13 @@ exit1:
 		}
 		free(ctx.ifaces);
 	}
+	free_options(&ctx, ifo);
 #ifdef HAVE_OPEN_MEMSTREAM
 	if (ctx.script_fp)
 		fclose(ctx.script_fp);
 #endif
 	free(ctx.script_buf);
 	free(ctx.script_env);
-	free_options(&ctx, ifo);
 	rt_dispose(&ctx);
 	free(ctx.duid);
 	if (ctx.link_fd != -1) {
diff --git a/src/if-options.c b/src/if-options.c
index 04e519ee..19337e04 100644
--- a/src/if-options.c
+++ b/src/if-options.c
@@ -2612,6 +2612,7 @@ free_options(struct dhcpcd_ctx *ctx, struct if_options *ifo)
 {
 	size_t i;
 #ifdef RT_FREE_ROUTE_TABLE
+	struct interface *ifp;
 	struct rt *rt;
 #endif
 	struct dhcp_opt *opt;
@@ -2640,9 +2641,12 @@ free_options(struct dhcpcd_ctx *ctx, struct if_options *ifo)
 	/* Stupidly, we don't know the interface when creating the options.
 	 * As such, make sure each route has one so they can goto the
 	 * free list. */
-	RB_TREE_FOREACH(rt, &ifo->routes) {
-		if (rt->rt_ifp == NULL)
-			rt->rt_ifp = TAILQ_FIRST(ctx->ifaces);
+	ifp = ctx->ifaces != NULL ? TAILQ_FIRST(ctx->ifaces) : NULL;
+	if (ifp != NULL) {
+		RB_TREE_FOREACH(rt, &ifo->routes) {
+			if (rt->rt_ifp == NULL)
+				rt->rt_ifp = ifp;
+		}
 	}
 #endif
 	rt_headclear0(ctx, &ifo->routes, AF_UNSPEC);