On 10/4/23 22:54, Greg Joyce wrote:
On Tue, 2023-10-03 at 12:02 +0200, Milan Broz wrote:The commit 3bfeb61256643281ac4be5b8a57e9d9da3db4335 introduced the use of keyring for sed-opal. Unfortunately, there is also a possibility to save the Opal key used in opal_lock_unlock(). This patch switches the order of operation, so the cached key is used instead of failure for opal_get_key. The problem was found by the cryptsetup Opal test recently added to the cryptsetup tree. Fixes: 3bfeb6125664 ("block: sed-opal: keyring support for SED keys") Tested-by: Ondrej Kozina <okozina@xxxxxxxxxx> Signed-off-by: Milan Broz <gmazyland@xxxxxxxxx> --- block/sed-opal.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/block/sed-opal.c b/block/sed-opal.c index 6d7f25d1711b..04f38a3f5d95 100644 --- a/block/sed-opal.c +++ b/block/sed-opal.c @@ -2888,12 +2888,11 @@ static int opal_lock_unlock(struct opal_dev *dev, if (lk_unlk->session.who > OPAL_USER9) return -EINVAL; - ret = opal_get_key(dev, &lk_unlk->session.opal_key); - if (ret) - return ret; mutex_lock(&dev->dev_lock); opal_lock_check_for_saved_key(dev, lk_unlk); - ret = __opal_lock_unlock(dev, lk_unlk); + ret = opal_get_key(dev, &lk_unlk->session.opal_key); + if (!ret) + ret = __opal_lock_unlock(dev, lk_unlk);This is relying on opal_get_key() returning 0 to decide if __opal_lock_unlock() is called. Is this really what you want? It seems that you would want to unlock if the key is a LUKS key, even if opal_get_key() returns non-zero.
I think it is ok. That was logic introduced in your keyring patch anyway. I just fixed that if key is cached (stored in OPAL struct), that key is used and subsequent opal_get_key() does nothing, returning 0. The story is here that both OPAL lock and unlock need key, while LUKS logic never required key for lock (deactivation), so we rely on the cached OPAL key here. We do not need any key stored for unlocking (that is always decrypted from a keyslot) (I think requiring key for locking range is a design mistake in OPAL but that's not relevant for now :-) Milan
mutex_unlock(&dev->dev_lock); return ret;
