linux-kernel - Re: [PATCH RFC v11 11/19] dm verity: set DM_TARGET

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]

Message-ID: <85311850a862fe6ccb946634429b890a.paul@paul-moore.com>
Date:   Mon, 23 Oct 2023 23:52:29 -0400
From:   Paul Moore <paul@...l-moore.com>
To:     Fan Wu <wufan@...ux.microsoft.com>, corbet@....net,
        zohar@...ux.ibm.com, jmorris@...ei.org, serge@...lyn.com,
        tytso@....edu, ebiggers@...nel.org, axboe@...nel.dk,
        agk@...hat.com, snitzer@...nel.org, eparis@...hat.com
Cc:     linux-doc@...r.kernel.org, linux-integrity@...r.kernel.org,
        linux-security-module@...r.kernel.org,
        linux-fscrypt@...r.kernel.org, linux-block@...r.kernel.org,
        dm-devel@...hat.com, audit@...r.kernel.org,
        roberto.sassu@...wei.com, linux-kernel@...r.kernel.org,
        Fan Wu <wufan@...ux.microsoft.com>
Subject: Re: [PATCH RFC v11 11/19] dm verity: set DM_TARGET_SINGLETON feature  flag

On Oct  4, 2023 Fan Wu <wufan@...ux.microsoft.com> wrote:
> 
> The device-mapper has a flag to mark targets as singleton, which is a
> required flag for immutable targets. Without this flag, multiple
> dm-verity targets can be added to a mapped device, which has no
> practical use cases and will let dm_table_get_immutable_target return
> NULL. This patch adds the missing flag, restricting only one
> dm-verity target per mapped device.
> 
> Signed-off-by: Fan Wu <wufan@...ux.microsoft.com>
> ---
> v1-v10:
>   + Not present
> ---
>  drivers/md/dm-verity-target.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

This seems reasonable to me and matches with other users of
DM_TARGET_IMMUTABLE.

Alasdair, Mike, can we get an ACK on this?

> diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
> index 26adcfea0302..80673b66c194 100644
> --- a/drivers/md/dm-verity-target.c
> +++ b/drivers/md/dm-verity-target.c
> @@ -1503,7 +1503,7 @@ int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, unsigned i
>  
>  static struct target_type verity_target = {
>  	.name		= "verity",
> -	.features	= DM_TARGET_IMMUTABLE,
> +	.features	= DM_TARGET_SINGLETON | DM_TARGET_IMMUTABLE,
>  	.version	= {1, 9, 0},
>  	.module		= THIS_MODULE,
>  	.ctr		= verity_ctr,
> -- 
> 2.25.1

--
paul-moore.com