[PATCH 5/6] rockchip: puma-rk3399: fix modified boot_targets detection

[Kever Yang]

On 2023/11/8 22:20, Quentin Schulz wrote:
> From: Quentin Schulz <quentin.schulz at theobroma-systems.com>
>
> U-Boot proper automatically modifies boot_targets to swap the order in
> which MMC storage media are used for standard boot based on which MMC
> storage medium was used to load U-Boot proper. This is however only done
> if the user has not changed it manually, therefore a check between the
> default and current value is done.
>
> This used to work fine until the migration to standard boot where
> boot_targets value size in the default environment went above the 32
> characters that env_get_default function can return, thus resulting in a
> truncated variable.
>
> Therefore the check between default and current value would always fail.
>
> By using the newly added env_get_default_into function, a buffer of
> the appropriate size can be allocated on the stack to get the whole
> value of boot_targets in the default environment and thus fixing the
> check.
>
> Cc: Quentin Schulz <foss+uboot at 0leil.net>
> Signed-off-by: Quentin Schulz <quentin.schulz at theobroma-systems.com>
Reviewed-by: Kever Yang <kever.yang at rock-chips.com>

Thanks,
- Kever
> ---
>   board/theobroma-systems/puma_rk3399/puma-rk3399.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/board/theobroma-systems/puma_rk3399/puma-rk3399.c b/board/theobroma-systems/puma_rk3399/puma-rk3399.c
> index 1b7a39b0474..df667fae5fc 100644
> --- a/board/theobroma-systems/puma_rk3399/puma-rk3399.c
> +++ b/board/theobroma-systems/puma_rk3399/puma-rk3399.c
> @@ -54,7 +54,9 @@ static int setup_boottargets(void)
>   {
>   	const char *boot_device =
>   		ofnode_read_chosen_string("u-boot,spl-boot-device");
> -	char *env_default, *env;
> +	char env_default[sizeof(BOOT_TARGETS)];
> +	char *env;
> +	int ret;
>   
>   	if (!boot_device) {
>   		debug("%s: /chosen/u-boot,spl-boot-device not set\n",
> @@ -63,7 +65,10 @@ static int setup_boottargets(void)
>   	}
>   	debug("%s: booted from %s\n", __func__, boot_device);
>   
> -	env_default = env_get_default("boot_targets");
> +	ret = env_get_default_into("boot_targets", env_default,
> +				   sizeof(env_default));
> +	if (ret < 0)
> +		env_default[0] = '\0';
>   	env = env_get("boot_targets");
>   	if (!env) {
>   		debug("%s: boot_targets does not exist\n", __func__);
>