[PATCH] fastboot: only look up real partition names when no alias exists

[Sean Anderson]

Hi Matthias,

On 12/16/21 5:26 AM, Matthias Schiffer wrote:
> Having U-Boot look up the passed partition name even though an alias
> exists is unexpected, leading to warning messages (when the alias name
> doesn't exist as a real partition name) or the use of the wrong
> partition.
>
> Change part_get_info_by_name_or_alias() to consider real partitions
> names only if no alias of the same name exists, allowing to use aliases
> to override the configuration for existing partition names.

Much saner IMO.

I think the correct move in the long term is to add a "quiet"
parameter to do_get_part_info (and all its helpers). This is OK as an
incremental improvement.

> Also change one use of strcpy() to strlcpy().
>
> Signed-off-by: Matthias Schiffer <matthias.schiffer at ew.tq-group.com>
> ---
>   drivers/fastboot/fb_mmc.c | 29 ++++++++++++-----------------
>   1 file changed, 12 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/fastboot/fb_mmc.c b/drivers/fastboot/fb_mmc.c
> index 2738dc836e..fb7791d9da 100644
> --- a/drivers/fastboot/fb_mmc.c
> +++ b/drivers/fastboot/fb_mmc.c
> @@ -104,23 +104,18 @@ static int part_get_info_by_name_or_alias(struct blk_desc **dev_desc,
>   					  const char *name,
>   					  struct disk_partition *info)
>   {
> -	int ret;
> -
> -	ret = do_get_part_info(dev_desc, name, info);
> -	if (ret < 0) {
> -		/* strlen("fastboot_partition_alias_") + PART_NAME_LEN + 1 */
> -		char env_alias_name[25 + PART_NAME_LEN + 1];
> -		char *aliased_part_name;
> -
> -		/* check for alias */
> -		strcpy(env_alias_name, "fastboot_partition_alias_");
> -		strlcat(env_alias_name, name, sizeof(env_alias_name));
> -		aliased_part_name = env_get(env_alias_name);
> -		if (aliased_part_name != NULL)
> -			ret = do_get_part_info(dev_desc, aliased_part_name,
> -					       info);
> -	}
> -	return ret;
> +	/* strlen("fastboot_partition_alias_") + PART_NAME_LEN + 1 */
> +	char env_alias_name[25 + PART_NAME_LEN + 1];
> +	char *aliased_part_name;
> +
> +	/* check for alias */
> +	strlcpy(env_alias_name, "fastboot_partition_alias_", sizeof(env_alias_name));
> +	strlcat(env_alias_name, name, sizeof(env_alias_name));
> +	aliased_part_name = env_get(env_alias_name);
> +	if (aliased_part_name)
> +		name = aliased_part_name;
> +
> +	return do_get_part_info(dev_desc, name, info);
>   }
>
>   /**
>

Reviewed-by: Sean Anderson <sean.anderson at seco.com>

--Sean