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In-Reply-To: <f602429ce0f419c2abc3ae5a0e705e1368ac5650.1674682056.git.rgb@redhat.com>
From:   Paul Moore <paul@paul-moore.com>
Date:   Fri, 27 Jan 2023 17:43:02 -0500
Message-ID: <CAHC9VhQiy9vP7BdQk+SXG7gQKAqOAqbYtU+c9R0_ym0h4bgG7g@mail.gmail.com>
Subject: Re: [PATCH v1 2/2] io_uring,audit: do not log IORING_OP_*GETXATTR
To:     Richard Guy Briggs <rgb@redhat.com>
Cc:     Linux-Audit Mailing List <linux-audit@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>, io-uring@vger.kernel.org,
        Eric Paris <eparis@parisplace.org>,
        Steve Grubb <sgrubb@redhat.com>, Stefan Roesch <shr@fb.com>,
        Christian Brauner <brauner@kernel.org>,
        Jens Axboe <axboe@kernel.dk>,
        Pavel Begunkov <asml.silence@gmail.com>
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On Fri, Jan 27, 2023 at 12:24 PM Richard Guy Briggs <rgb@redhat.com> wrote:
>
> Getting XATTRs is not particularly interesting security-wise.
>
> Suggested-by: Steve Grubb <sgrubb@redhat.com>
> Fixes: a56834e0fafe ("io_uring: add fgetxattr and getxattr support")
> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> ---
>  io_uring/opdef.c | 2 ++
>  1 file changed, 2 insertions(+)

Depending on your security policy, fetching file data, including
xattrs, can be interesting from a security perspective.  As an
example, look at the SELinux file/getattr permission.

https://github.com/SELinuxProject/selinux-notebook/blob/main/src/object_classes_permissions.md#common-file-permissions

> diff --git a/io_uring/opdef.c b/io_uring/opdef.c
> index a2bf53b4a38a..f6bfe2cf078c 100644
> --- a/io_uring/opdef.c
> +++ b/io_uring/opdef.c
> @@ -462,12 +462,14 @@ const struct io_op_def io_op_defs[] = {
>         },
>         [IORING_OP_FGETXATTR] = {
>                 .needs_file = 1,
> +               .audit_skip             = 1,
>                 .name                   = "FGETXATTR",
>                 .prep                   = io_fgetxattr_prep,
>                 .issue                  = io_fgetxattr,
>                 .cleanup                = io_xattr_cleanup,
>         },
>         [IORING_OP_GETXATTR] = {
> +               .audit_skip             = 1,
>                 .name                   = "GETXATTR",
>                 .prep                   = io_getxattr_prep,
>                 .issue                  = io_getxattr,
> --
> 2.27.0

-- 
paul-moore.com