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Date:   Thu, 22 Oct 2020 17:14:57 +0100
From:   Alessio Balsini <balsini@android.com>
To:     Antonio SJ Musumeci <trapexit@spawn.link>
Cc:     Miklos Szeredi <miklos@szeredi.hu>,
        Alessio Balsini <balsini@android.com>,
        Akilesh Kailash <akailash@google.com>,
        Amir Goldstein <amir73il@gmail.com>,
        David Anderson <dvander@google.com>,
        Giuseppe Scrivano <gscrivan@redhat.com>,
        Jann Horn <jannh@google.com>, Jens Axboe <axboe@kernel.dk>,
        Martijn Coenen <maco@android.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Lawrence <paullawrence@google.com>,
        Stefano Duo <stefanoduo@google.com>,
        Zimuzo Ezeozue <zezeozue@google.com>,
        fuse-devel <fuse-devel@lists.sourceforge.net>,
        kernel-team <kernel-team@android.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V9 2/4] fuse: Trace daemon creds
Message-ID: <20201022161457.GB36774@google.com>
References: <20200924131318.2654747-1-balsini@android.com>
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On Wed, Sep 30, 2020 at 03:16:20PM -0400, Antonio SJ Musumeci wrote:
> On 9/30/2020 2:45 PM, Miklos Szeredi wrote:
> > On Thu, Sep 24, 2020 at 3:13 PM Alessio Balsini <balsini@android.com> wrote:
> > > Add a reference to the FUSE daemon credentials, so that they can be used to
> > > temporarily raise the user credentials when accessing lower file system
> > > files in passthrough.
> > Hmm, I think it would be better to store the creds of the ioctl()
> > caller together with the open file.   The mounter may deliberately
> > have different privileges from the process doing the actual I/O.
> > 
> > Thanks,
> > Miklos
> 
> 
> In my usecase I'm changing euid/egid of the thread to whichever the uid/gid
> was passed to the server which is otherwise running as root.
> 

Ack, in the next patch set I will store the creds of the ioctl() caller.

Thanks,
Alessio