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

[Coiby Xu]

On Wed, Aug 05, 2026 at 05:22:39PM +0530, Sourabh Jain wrote:
> 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@xxxxxxxxx>
> > ---
> >  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.

I'll change it in next version, thanks!

> Rest of changes looks good to me.
> Reviewed-by: Sourabh Jain <sourabhjain@xxxxxxxxxxxxx>

And thanks for reviewing and ack'ing the patch!

> >  }

--
Best regards,
Coiby