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Fri, 12 Dec 2025 21:06:46 -0800 (PST) From: Dan Klishch To: legion@kernel.org, linux-kernel@vger.kernel.org Cc: ebiederm@xmission.com, viro@zeniv.linux.org.uk, keescook@chromium.org, containers@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, Dan Klishch Subject: Re: [RESEND PATCH v6 0/5] proc: subset=pid: Relax check of mount visibility Date: Sat, 13 Dec 2025 00:06:38 -0500 Message-ID: <20251213050639.735940-1-danilklishch@gmail.com> X-Mailer: git-send-email 2.51.2 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hello Alexey, Would it be possible to revive this patch series? I wanted to add an additional downstream use case that would benefit from this work. In particular, I am trying to run the sandbox sunwalker-box [1] without root privileges and/or inside a container. The sandbox aims to prevent cross-run communication via side channels, and PID allocation is one such channel. Therefore, it creates a new PID namespace and mounts the corresponding procfs instance inside of the sandbox. This currently works without a real root when procfs is fully accessible, but obviously fails otherwise. Thanks, Dan Klishch [1] https://github.com/purplesyringa/sunwalker-box/