Re: [PATCH 1/4] proc/bootconfig: Fix to use correct quotes for value

[Steven Rostedt]

On Sat, 13 Jun 2020 00:23:18 +0900
Masami Hiramatsu <mhira...@kernel.org> wrote:

> Fix /proc/bootconfig to show the correctly choose the
> double or single quotes according to the value.
> 
> If a bootconfig value includes a double quote character,
> we must use single-quotes to quote that value.
> 
> Fixes: c1a3c36017d4 ("proc: bootconfig: Add /proc/bootconfig to show boot 
> config list")
> Cc: sta...@vger.kernel.org
> Signed-off-by: Masami Hiramatsu <mhira...@kernel.org>
> ---
>  fs/proc/bootconfig.c |   13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/proc/bootconfig.c b/fs/proc/bootconfig.c
> index 9955d75c0585..930d1dae33eb 100644
> --- a/fs/proc/bootconfig.c
> +++ b/fs/proc/bootconfig.c
> @@ -27,6 +27,7 @@ static int __init copy_xbc_key_value_list(char *dst, size_t 
> size)
>  {
>       struct xbc_node *leaf, *vnode;
>       const char *val;
> +     char q;
>       char *key, *end = dst + size;
>       int ret = 0;

Hmm, shouldn't the above have the upside-down xmas tree format?

        struct xbc_node *leaf, *vnode;
        char *key, *end = dst + size;
        const char *val;
        char q;
        int ret = 0;


Looks a little better that way. But anyway, more meat below.

>  
> @@ -41,16 +42,20 @@ static int __init copy_xbc_key_value_list(char *dst, 
> size_t size)
>                       break;
>               dst += ret;
>               vnode = xbc_node_get_child(leaf);
> -             if (vnode && xbc_node_is_array(vnode)) {
> +             if (vnode) {
>                       xbc_array_for_each_value(vnode, val) {
> -                             ret = snprintf(dst, rest(dst, end), "\"%s\"%s",
> -                                     val, vnode->next ? ", " : "\n");

The above is a functional change that is not described in the change
log.

You use to have:

        if (vnode && xbc_node_is_array(vnode)) {
                xbc_array_for_each_value() {
                        [..]
                }
        } else {
                [..]
        }

And now have:

        if (vnode) {
                xbc_array_for_each_value() {
                        [..]
                }
        } else {
                [..]
        }

Is "vnode" equivalent to "vnode && xbc_node_is_array(vnode)" ?

Why was this change made? It seems out of scope with the change log?

-- Steve


> +                             if (strchr(val, '"'))
> +                                     q = '\'';
> +                             else
> +                                     q = '"';
> +                             ret = snprintf(dst, rest(dst, end), "%c%s%c%s",
> +                                     q, val, q, vnode->next ? ", " : "\n");
>                               if (ret < 0)
>                                       goto out;
>                               dst += ret;
>                       }
>               } else {
> -                     ret = snprintf(dst, rest(dst, end), "\"%s\"\n", val);
> +                     ret = snprintf(dst, rest(dst, end), "\"\"\n");
>                       if (ret < 0)
>                               break;
>                       dst += ret;