[PATCH v3 07/10] crash_dump: Improve readability of config_keys_restore_store

[Sourabh Jain]

On 29/07/26 09:06, Coiby Xu wrote:
> config_keys_restore_store currently doesn't validate the user input
> before restoring dm-crypt keys. Although it's not necessary for the case
> of vmcore dumping, it's better to do it for the sake of consistency and
> code readability. Also check the return code of
> restore_dm_crypt_keys_to_thread_keyring.
>
> Fixes: 62f17d9df692 ("crash_dump: retrieve dm crypt keys in kdump kernel")
> Signed-off-by: Coiby Xu <coiby.xu at gmail.com>
> ---
>   kernel/crash_dump_dm_crypt.c | 13 ++++++++++---
>   1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/kernel/crash_dump_dm_crypt.c b/kernel/crash_dump_dm_crypt.c
> index 3ee01996778f..1f4549956824 100644
> --- a/kernel/crash_dump_dm_crypt.c
> +++ b/kernel/crash_dump_dm_crypt.c
> @@ -370,12 +370,19 @@ static ssize_t config_keys_restore_show(struct config_item *item, char *page)
>   static ssize_t config_keys_restore_store(struct config_item *item,
>   					  const char *page, size_t count)
>   {
> -	if (!restore)
> -		restore_dm_crypt_keys_to_thread_keyring();
> +	bool val;
>   
> -	if (kstrtobool(page, &restore))
> +	if (kstrtobool(page, &val))
>   		return -EINVAL;
>   
> +	if (val) {
> +		if (restore) {
> +			pr_warn("dm-crypt keys already restored!\n");
> +			return count;
> +		} else if (!restore_dm_crypt_keys_to_thread_keyring())
> +			restore = true;
> +	}
> +
>   	return count;

Nit: returns count even when restore fails.

Rest of changes looks good to me.
Reviewed-by: Sourabh Jain <sourabhjain at linux.ibm.com>

>   }
>