[PATCH 4/7] smbios: string table always needs two terminating NUL bytes

[Matthias Brugger]

On Mon, Jan 29, 2024 at 10:04:50PM +0100, Heinrich Schuchardt wrote:
> The string section of the different SMBIOS structures is always terminated
> by two NUL bytes even if there is no string at all. This is described in
> section 6.1.3 "Text string" of the SMBIOS 3.7.0 specification.
> 
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>

I send the very same patch some years ago [1], unfortunately it got
somehow lost. Happy to see you trying to fix the same problem, so:
Reviewed-by: Matthias Brugger <mbrugger at suse.com>


[1] https://patchwork.ozlabs.org/project/uboot/patch/20210406090435.19357-1-matthias.bgg@kernel.org/ 

> ---
>  lib/smbios.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/lib/smbios.c b/lib/smbios.c
> index 7bd9805fec0..81908e89610 100644
> --- a/lib/smbios.c
> +++ b/lib/smbios.c
> @@ -311,6 +311,9 @@ int smbios_update_version(const char *version)
>   */
>  static int smbios_string_table_len(const struct smbios_ctx *ctx)
>  {
> +	/* If the structure contains no string it is followed by to NUL bytes */
> +	if (ctx->next_ptr == ctx->eos)
> +		return 2;
>  	/* Allow for the final \0 after all strings */
>  	return (ctx->next_ptr + 1) - ctx->eos;
>  }
> -- 
> 2.43.0