Re: [PATCH] bootconfig: remove unreachable index checks in xbc_verify_tree()

[Masami Hiramatsu (Google) <mhiramat@kernel.org>]

On Sat,  5 Sep 2026 23:16:36 +0900
Sang-Heon Jeon <ekffu200098@gmail.com> wrote:

> xbc_verify_tree() checks that every node's next and child are below
> xbc_node_num. Both fields store the index of an existing node, which
> is below xbc_node_num.

This is a kind of foolpoof/defensive checking. (so I call it verify.)

> 
> So remove the checks.
> 
> No functional change.

Hmm, OK, I think we should decouple the logic/implementation
verification from runtime verification (e.g. wrong format)
and move the former to tools/bootconfig.

Thank you,

> 
> Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
> ---
>  lib/bootconfig.c | 13 +------------
>  1 file changed, 1 insertion(+), 12 deletions(-)
> 
> diff --git a/lib/bootconfig.c b/lib/bootconfig.c
> index 89c88e359179..d383430637ee 100644
> --- a/lib/bootconfig.c
> +++ b/lib/bootconfig.c
> @@ -1005,7 +1005,7 @@ static int __init xbc_close_brace(char **k, char *n)
>  
>  static int __init xbc_verify_tree(void)
>  {
> -	int i, depth;
> +	int depth;
>  	size_t len, wlen;
>  	struct xbc_node *n, *m;
>  
> @@ -1022,17 +1022,6 @@ static int __init xbc_verify_tree(void)
>  		return -ENOENT;
>  	}
>  
> -	for (i = 0; i < xbc_node_num; i++) {
> -		if (xbc_nodes[i].next >= xbc_node_num) {
> -			return xbc_parse_error("No closing brace",
> -				xbc_node_get_data(xbc_nodes + i));
> -		}
> -		if (xbc_nodes[i].child >= xbc_node_num) {
> -			return xbc_parse_error("Broken child node",
> -				xbc_node_get_data(xbc_nodes + i));
> -		}
> -	}
> -
>  	/* Key tree limitation check */
>  	n = &xbc_nodes[0];
>  	depth = 1;
> -- 
> 2.43.0
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>