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([2408:8220:6b4b:bb0:3bc5:a2cf:f997:7a80]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-392d51e3467sm3436132a91.8.2026.08.11.03.49.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Aug 2026 03:49:27 -0700 (PDT) From: Gu Lingguang To: Alexey Gladkov , Christian Brauner Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, containers@lists.linux.dev, Alexander Viro , "Eric W . Biederman" , Aleksa Sarai , "Serge E . Hallyn" , Gu Lingguang Subject: Re: [RFC] mnt_already_visible(): should regular-file mountpoints participate in the visibility check? Date: Tue, 11 Aug 2026 18:49:21 +0800 Message-ID: <20260811104921.8099-1-liu83783@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260811-obsession-propeller-eiskalt-a2ca8b0a1017@brauner> References: <20260811-obsession-propeller-eiskalt-a2ca8b0a1017@brauner> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Thanks to both of you for the replies. @legion: The /proc/keys and /proc/interrupts case you raised is one I missed, and it shows that a new mount can grant access that the container's creators do not want to grant. I withdraw the suggestion. @Brauner: you're right, and I apologize for the length. I'll keep future questions to the bare minimum. Thanks, Gu Lingguang