Eric,
Am Donnerstag, 21. Februar 2019, 06:49:39 CET schrieb Eric Biggers:
> Hi Richard,
>
> On Thu, Feb 21, 2019 at 12:52:38AM +0100, Richard Weinberger wrote:
> > On Wed, Feb 20, 2019 at 7:55 AM Eric Biggers <ebiggers@xxxxxxxxxx> wrote:
> > > +#define FSCRYPT_FS_KEYRING_DESCRIPTION_SIZE \
> > > + (CONST_STRLEN("fscrypt-") + FIELD_SIZEOF(struct super_block, s_id))
> > > +
> > > +#define FSCRYPT_MK_DESCRIPTION_SIZE (2 * FSCRYPT_KEY_DESCRIPTOR_SIZE + 1)
> > > +
> > > +static void format_fs_keyring_description(
> > > + char description[FSCRYPT_FS_KEYRING_DESCRIPTION_SIZE],
> > > + const struct super_block *sb)
> > > +{
> > > + sprintf(description, "fscrypt-%s", sb->s_id);
> > > +}
> >
> > I fear ->s_id is not the right thing.
> > For filesystems such as ext4 ->s_id is the name of the backing block device,
> > so it is per filesysem instance unique.
> > But this is not guaranteed. For UBIFS ->s_id is just "ubifs", always.
> > So the names will clash.
> >
>
> What name do you suggest using for UBIFS filesystems? The keyring name could be
> set by the filesystem via a fscrypt_operations callback if needed.
IMHO the BDI name should be used.
> Note that the keyring name isn't particularly important, since the ioctls will
> work regardless. But we might as well choose something logical, since the
> keyring name will still show up in /proc/keys.
I'm not done with reviewing your patches, but will it be possible to use keyctl?
For the a unique name is helpful. :)
Thanks,
//richard
