[PATCH] fastboot: fix partition name truncation in environment lookup

[Sean Anderson]

On 7/30/21 8:23 AM, Matthias Schiffer wrote:
> strlcat() need to be passed the full buffer length. The incorrect call
> caused truncation of partition names for fastboot_raw_partition_... and
> fastboot_partition_alias_... env lookup to much less than PART_NAME_LEN.
> 
> Fixes: 69a752983171 ("fastboot: Fix possible buffer overrun")
> Signed-off-by: Matthias Schiffer <matthias.schiffer at ew.tq-group.com>
> ---
>   drivers/fastboot/fb_mmc.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/fastboot/fb_mmc.c b/drivers/fastboot/fb_mmc.c
> index 2f3837e559..33fd6c21af 100644
> --- a/drivers/fastboot/fb_mmc.c
> +++ b/drivers/fastboot/fb_mmc.c
> @@ -40,7 +40,7 @@ static int raw_part_get_info_by_name(struct blk_desc *dev_desc,
>   
>   	/* check for raw partition descriptor */
>   	strcpy(env_desc_name, "fastboot_raw_partition_");
> -	strlcat(env_desc_name, name, PART_NAME_LEN);
> +	strlcat(env_desc_name, name, sizeof(env_desc_name));
>   	raw_part_desc = strdup(env_get(env_desc_name));
>   	if (raw_part_desc == NULL)
>   		return -ENODEV;
> @@ -114,7 +114,7 @@ static int part_get_info_by_name_or_alias(struct blk_desc **dev_desc,
>   
>   		/* check for alias */
>   		strcpy(env_alias_name, "fastboot_partition_alias_");
> -		strlcat(env_alias_name, name, PART_NAME_LEN);
> +		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,
> 

Reviewed-by: Sean Anderson <seanga2 at gmail.com>