Re: [PATCH] commands: keystore: work around missing initialization false positive

[Sascha Hauer]

On Mon, Oct 09, 2023 at 01:53:16PM +0200, Ahmad Fatoum wrote:
> clang is unhappy about this. While I can't see how s_len could be used
> uninitialized, there's value in silencing these warnings, so the real
> issues are not as easy to overlook.

Well we have:

        if (file)
                read_file_2(file, &s_len, (void *)&secret_str, FILESIZE_MAX);
        else if (secret_str)
                s_len = strlen(secret_str);

So s_len could be uninitialized after this when both file and secret_str
are NULL. This can't happen due to:

        if (!do_remove && !file && !secret_str)
                return COMMAND_ERROR_USAGE;

and later:

        if (do_remove) {
                ...
                return 0;
        }

While I agree that s_len shouldn't slip through uninitialized this is
really buried in the code and I do not wonder when a compiler doesn't
catch this correctly.

Anyway, applied, thanks

Sascha

> 
> Signed-off-by: Ahmad Fatoum <a.fat...@pengutronix.de>
> ---
>  commands/keystore.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/commands/keystore.c b/commands/keystore.c
> index 4922cf1bebe9..40bcb7105d75 100644
> --- a/commands/keystore.c
> +++ b/commands/keystore.c
> @@ -17,7 +17,7 @@ static int do_keystore(int argc, char *argv[])
>       const char *file = NULL;
>       char *secret_str = NULL;
>       void *secret;
> -     size_t s_len;
> +     size_t s_len = 0;
>  
>       while ((opt = getopt(argc, argv, "rs:f:")) > 0) {
>               switch (opt) {
> -- 
> 2.39.2
> 
> 
> 

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