linux-kernel - Re: [PATCH v2 3/8] block: blk-crypto: introduce blk_crypto_bio_sectors

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 15 Apr 2021 12:33:02 -0700
From:   Eric Biggers <ebiggers@...nel.org>
To:     Satya Tangirala <satyat@...gle.com>
Cc:     linux-block@...r.kernel.org, linux-kernel@...r.kernel.org,
        Jens Axboe <axboe@...nel.dk>
Subject: Re: [PATCH v2 3/8] block: blk-crypto: introduce
 blk_crypto_bio_sectors_alignment()

On Thu, Mar 25, 2021 at 09:26:04PM +0000, Satya Tangirala wrote:
> The size of any bio must be aligned to the data unit size of the bio crypt
> context (if it exists) of that bio. This must also be ensured whenever a
> bio is split. Introduce blk_crypto_bio_sectors_alignment() that returns
> the required alignment in sectors. The number of sectors passed to
> any call of bio_split() should be aligned to
> blk_crypto_bio_sectors_alignment().

"should be aligned" => "must be aligned"?

> +/*
> + * Returns the alignment requirement for the number of sectors in this bio based
> + * on its bi_crypt_context. Any bios split from this bio must follow this
> + * alignment requirement as well.
> + */

It would be helpful to expand this comment a bit to explictly mention that the
size of the bio must be a multiple of the crypto data unit size that was
selected by the submitter of the bio, which is the granularity of
encryption/decryption.  Keep in mind that people reading this code won't
necessarily be familiar with inline encryption.

- Eric