Re: [PATCH] fscrypt: fix keyring memory leak on mount failure

From: Christian Brauner
Date: Wed Oct 19 2022 - 08:01:14 EST


On Tue, Oct 11, 2022 at 02:38:38PM -0700, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> Commit d7e7b9af104c ("fscrypt: stop using keyrings subsystem for
> fscrypt_master_key") moved the keyring destruction from __put_super() to
> generic_shutdown_super() so that the filesystem's block device(s) are
> still available. Unfortunately, this causes a memory leak in the case
> where a mount is attempted with the test_dummy_encryption mount option,
> but the mount fails after the option has already been processed.
>
> To fix this, attempt the keyring destruction in both places.
>
> Reported-by: syzbot+104c2a89561289cec13e@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: d7e7b9af104c ("fscrypt: stop using keyrings subsystem for fscrypt_master_key")
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
> ---

Looks good,
Reviewed-by: Christian Brauner (Microsoft) <brauner@xxxxxxxxxx>