[PATCH v2 7/9] crash_dump: Improve readability of config_keys_restore_store

[Coiby Xu]

On Wed, May 06, 2026 at 08:03:44PM +0530, Sourabh Jain wrote:
>
>
>On 02/05/26 05:13, 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 | 10 +++++++---
>>  1 file changed, 7 insertions(+), 3 deletions(-)
>>
>>diff --git a/kernel/crash_dump_dm_crypt.c b/kernel/crash_dump_dm_crypt.c
>>index 545d712428d3..36e51807d94f 100644
>>--- a/kernel/crash_dump_dm_crypt.c
>>+++ b/kernel/crash_dump_dm_crypt.c
>>@@ -358,12 +358,16 @@ 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 && !restore) {
>>+		if (!restore_dm_crypt_keys_to_thread_keyring())
>>+			restore = true;
>>+	}
>
>Nit:
>I think it would be good to warn the user if they try to
>restore it when it has already been restored.

Thanks for the suggestion! I'll apply it to v3.

>
>
>- Sourabh Jain
>>+
>>  	return count;
>>  }
>

-- 
Best regards,
Coiby