From: Ondrej Zajicek (work) <santiago@crfreenet.org>
Date: Fri, 17 Feb 2017 21:54:06 +0000 (+0100)
Subject: Static: Fix bug in static route filter expressions
X-Git-Tag: v2.0.0-pre1~4^2~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=30c734fc73648e4c43af4f45e68ac2de3d7ddea1;p=thirdparty%2Fbird.git

Static: Fix bug in static route filter expressions

During reconfiguration, old and new filter expressions in static routes
are compared using i_same() function. When filter expressions contain
function calls, it is necessary that old filter expressions are the
second argument in i_same(), as it is internally modified by i_same().
Otherwise pointers to old (and freed) data appear in the config
structure.

Thanks to Lennert Buytenhek for tracking and reporting the bug.
---

diff --git a/proto/static/static.c b/proto/static/static.c
index 0c088cd7f..849067b91 100644
--- a/proto/static/static.c
+++ b/proto/static/static.c
@@ -498,7 +498,8 @@ static_same_dest(struct static_route *x, struct static_route *y)
 static inline int
 static_same_rte(struct static_route *x, struct static_route *y)
 {
-  return static_same_dest(x, y) && i_same(x->cmds, y->cmds);
+  /* Note that i_same() requires arguments in (new, old) order */
+  return static_same_dest(x, y) && i_same(y->cmds, x->cmds);
 }