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From:   Jonathan Corbet <corbet@lwn.net>
To:     Ming Lei <ming.lei@redhat.com>, Jens Axboe <axboe@kernel.dk>
Cc:     linux-block@vger.kernel.org,
        ZiyangZhang <ZiyangZhang@linux.alibaba.com>,
        Ming Lei <ming.lei@redhat.com>,
        Stefan Hajnoczi <stefanha@redhat.com>
Subject: Re: [PATCH V3 6/6] ublk_drv: add mechanism for supporting
 unprivileged ublk device
In-Reply-To: <20221207123305.937678-7-ming.lei@redhat.com>
References: <20221207123305.937678-1-ming.lei@redhat.com>
 <20221207123305.937678-7-ming.lei@redhat.com>
Date:   Tue, 03 Jan 2023 13:35:14 -0700
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I have one quick question...

Ming Lei <ming.lei@redhat.com> writes:

> In case of UBLK_F_UNPRIVILEGED_DEV:
>
> 1) for command UBLK_CMD_ADD_DEV, it is always allowed, and user needs
> to provide owner's uid/gid in this command, so that udev can set correct
> ownership for the created ublk device, since the device owner uid/gid
> can be queried via command of UBLK_CMD_GET_DEV_INFO.

Why do you have the user provide the uid/gid rather than just using the
user's credentials directly?  It seems a bit strange to me to let
unprivileged users create devices with arbitrary ownership.  What am I
missing here?

Thanks,

jon