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	Creating a key binding which replaces itself (such as "bind x bind x lsw")
frees the command list bound to the key while it is still being executed, leading to a use after free. To prevent this, create a dead keys list and defer freeing replaced or removed key bindings until the main loop when the key binding will have finished executing. Found by Johan Friis when creating a key binding to reload his configuration file.
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		@@ -27,6 +27,7 @@
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SPLAY_GENERATE(key_bindings, key_binding, entry, key_bindings_cmp);
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struct key_bindings	key_bindings;
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struct key_bindings	dead_key_bindings;
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int
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key_bindings_cmp(struct key_binding *bd1, struct key_binding *bd2)
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@@ -48,12 +49,12 @@ key_bindings_add(int key, int can_repeat, struct cmd_list *cmdlist)
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{
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	struct key_binding	*bd;
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	if ((bd = key_bindings_lookup(key)) == NULL) {
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		bd = xmalloc(sizeof *bd);
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		bd->key = key;
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		SPLAY_INSERT(key_bindings, &key_bindings, bd);
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	} else
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		cmd_list_free(bd->cmdlist);
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	key_bindings_remove(key);
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	bd = xmalloc(sizeof *bd);
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	bd->key = key;
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	SPLAY_INSERT(key_bindings, &key_bindings, bd);
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	bd->can_repeat = can_repeat;
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	bd->cmdlist = cmdlist;
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}
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@@ -66,9 +67,20 @@ key_bindings_remove(int key)
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	if ((bd = key_bindings_lookup(key)) == NULL)
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		return;
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	SPLAY_REMOVE(key_bindings, &key_bindings, bd);
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	SPLAY_INSERT(key_bindings, &dead_key_bindings, bd);
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}
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	cmd_list_free(bd->cmdlist);
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	xfree(bd);
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void
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key_bindings_clean(void)
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{
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	struct key_binding	*bd;
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	while (!SPLAY_EMPTY(&dead_key_bindings)) {
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		bd = SPLAY_ROOT(&dead_key_bindings);
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		SPLAY_REMOVE(key_bindings, &dead_key_bindings, bd);
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		cmd_list_free(bd->cmdlist);
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		xfree(bd);
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	}
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}
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void
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@@ -162,6 +174,7 @@ key_bindings_free(void)
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{
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	struct key_binding	*bd;
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	key_bindings_clean();
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	while (!SPLAY_EMPTY(&key_bindings)) {
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		bd = SPLAY_ROOT(&key_bindings);
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		SPLAY_REMOVE(key_bindings, &key_bindings, bd);
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