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From: Catalin Marinas <catalin.marinas@arm.com>
To: Arnaud Lacombe <lacombar@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>,
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Subject: Re: Stale expression reference causing use-after-free
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Date: Tue, 21 Sep 2010 17:22:50 +0100
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diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index 7298806..e707aa2 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -107,7 +107,9 @@ static struct expr *menu_check_dep(struct expr *e)
 void menu_add_dep(struct expr *dep)
 {
 	current_entry->dep = expr_alloc_and(current_entry->dep, menu_check_dep(dep));
-	current_entry->dir_dep = current_entry->dep;
+	if (current_entry->dir_dep)
+		expr_free(current_entry->dir_dep);
+	current_entry->dir_dep = expr_copy(current_entry->dep);
 }
 
 void menu_set_type(int type)