Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20190617184711.21364-1-christian@brauner.io>
In-Reply-To: <20190617184711.21364-1-christian@brauner.io>
From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 17 Jun 2019 11:50:13 -0700
Message-ID: <CAHk-=wh+OWQ2s-NZC4RzfHtgNfhV9sbtP6dXV4WnsVRQ3A3hnA@mail.gmail.com>
Subject: Re: [PATCH] fs/namespace: fix unprivileged mount propagation
To:     Christian Brauner <christian@brauner.io>
Cc:     Al Viro <viro@zeniv.linux.org.uk>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        stable <stable@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Jun 17, 2019 at 11:47 AM Christian Brauner <christian@brauner.io> wrote:
>
> When propagating mounts across mount namespaces owned by different user
> namespaces it is not possible anymore to move or umount the mount in the
> less privileged mount namespace.

I will wait a short while in the hope of getting Al's ack for this,
but since it looks about as good as it likely can be, I suspect I'll
just apply it later today even without such an ack..

                    Linus