From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f47.google.com (mail-ed1-f47.google.com [209.85.208.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7ADD428466D for ; Mon, 25 Aug 2025 12:11:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756123862; cv=none; b=okFKUzR769whUqetoRmdVh1zJqlZADQIvL/w1mi41jbQB/9kdTXe1iSRldbMBXXU8Mh1SqZ+vGpo7aFMWHbMLkdZwz7YuiY5qaUvvcA/012aqo796DKPfP/TA3me4PyIL6LTj+GIgO+O8AqURkoLH9ivBJ6B2PSMI37N952+828= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756123862; c=relaxed/simple; bh=ZELCh/D+zvbWXmi/vnLHq3ROheCzOje8RshmDa5E5SE=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=QwhnEeM7TxfuiIDqfo4A0MzV7ZOI8d6F3KiuclgrVe/VUgI3vQu9IxkNANbwZpYO3Q8PYlK3J0MFVMFvsMeknilrWVeVUt4RwzHz8gTihr8MKSRpPspk5INMJuqMHHQCb1sCWkg65hM+r6hGLygDNWT9HnPNdZ+i+VWMtj9qPpw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org; spf=pass smtp.mailfrom=linuxfoundation.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=EXsnOBUI; arc=none smtp.client-ip=209.85.208.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linuxfoundation.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="EXsnOBUI" Received: by mail-ed1-f47.google.com with SMTP id 4fb4d7f45d1cf-61c26f3cf0dso4202134a12.1 for ; Mon, 25 Aug 2025 05:11:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; t=1756123858; x=1756728658; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=c7qE1QXaZwWjH9fqfq6LhKop+aIZ2HU5wia0HyWc8yw=; b=EXsnOBUIQeD/CRdYBg8nh5AqlISP2Hy6ZCKcXI+tpDaYC8V5PCLxwfux7utCI4i160 weUPk6Msl1yTuoomW01hTRpTiHjBnN57xCVFJssrXltmSRlRVNYxXrQH2/cw3YVVNiHy kk7txilKoO6YM8M5ns7IX8KhDMnv7J6XYZRJ0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756123858; x=1756728658; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=c7qE1QXaZwWjH9fqfq6LhKop+aIZ2HU5wia0HyWc8yw=; b=PCkF8NVHQuaf0lDyu0Qd3LY/vZD9LmkMjN6nZJF0BdaiUtWz+2oQupE1tMB8yP6+Se xB1sSANJs/M00vZ+AtdYMaM8A4pHyb5u2ro+5o4TxhCJixAi4XQn4x7q/eVoE2RF5rTf QLCjT6phRaOQvccZAIUETRok6HCo9dlBuzHs7dpTXvvxy4p5VUxphG0jRsIlW6iSewNq 6kasTjVYfUNruhhshSKiQxuKTGu3gzqwSD55oxXwHzcuWkswClMf7Md7V3W7StiTt8yw YcGYx+WMW4S/Of/7hCpAT9QqBTjdyot9UOCT3/ERm5XtcSr6HsCllUW7D2RsfULB4nsf higw== X-Gm-Message-State: AOJu0YyG9y2kc4KhvUfN97fC5jI6r5cYIKCoAmT2Cq8lKK965i1kozlw K/3EPAOxY/TRmeQgZljSuY+OOxHZGxyr3CwR9KbwNdpO1jO5l7Kb0WkKVbEF7Il0sxhTRy2E1qS AnnnI0pw= X-Gm-Gg: ASbGnctIl6W40oHiOgU/wxr301cjTl0TtAhgNfR7g1SKEcqpTb56L0FTEFDJgvqmhGq ElGcMxJKYAe5UTah8og7w7XvoJN85WMxcsAzp68bUOznuCi+IqqkGoiRNMgcPDpRakjkdMXgkav yA52FbtgmbDwKIMpnmXvh0AztMsDrAng7/AWXgazZGOzYd8rvkV+HNycxZ/T7KPIdF7JL/PeQPZ QPsVr/UVuX2NomnE+ktKTzXVfTcgdEG+DwnkicU+i/73gU0LknpuFTUlB9HDk1EqnVjbKjBjqJ7 xy8mgs/v8oL26PfnpNnGlrOgrifH4youFj4sMlEAbq1cYNz/5SLl5XcarAtf63vCijyNirXbbSO l3mCoV2LaAxzFAG4hpxSLSQE4H7j4S+s84m3fA/f4jmoutLahTwI1o647kLmriWU2s6gbCFQH X-Google-Smtp-Source: AGHT+IH3cplpjGExbae8pl+TAF1+dvUodzQ8yqN3qgALafwKbYXmTktAbePCHsPxH/Dxu8aLdE6Y6Q== X-Received: by 2002:a05:6402:348f:b0:61c:8742:21dc with SMTP id 4fb4d7f45d1cf-61c8742249dmr263958a12.17.1756123858496; Mon, 25 Aug 2025 05:10:58 -0700 (PDT) Received: from mail-ed1-f47.google.com (mail-ed1-f47.google.com. [209.85.208.47]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-61c312ad9e4sm4968607a12.17.2025.08.25.05.10.57 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 25 Aug 2025 05:10:57 -0700 (PDT) Received: by mail-ed1-f47.google.com with SMTP id 4fb4d7f45d1cf-61c26f3cf0dso4202069a12.1 for ; Mon, 25 Aug 2025 05:10:57 -0700 (PDT) X-Received: by 2002:a05:6402:4316:b0:61c:7743:7fb3 with SMTP id 4fb4d7f45d1cf-61c77438553mr1227430a12.1.1756123857233; Mon, 25 Aug 2025 05:10:57 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20250825044046.GI39973@ZenIV> <20250825044355.1541941-1-viro@zeniv.linux.org.uk> <20250825044355.1541941-20-viro@zeniv.linux.org.uk> In-Reply-To: <20250825044355.1541941-20-viro@zeniv.linux.org.uk> From: Linus Torvalds Date: Mon, 25 Aug 2025 08:10:40 -0400 X-Gmail-Original-Message-ID: X-Gm-Features: Ac12FXxl6L4JNGde4jQKUnV41a1IddBJUfMMALyJOYf4NEy6z9IX0E1_MzqV5lk Message-ID: Subject: Re: [PATCH 20/52] move_mount(2): take sanity checks in 'beneath' case into do_lock_mount() To: Al Viro Cc: linux-fsdevel@vger.kernel.org, brauner@kernel.org, jack@suse.cz Content-Type: text/plain; charset="UTF-8" On Mon, 25 Aug 2025 at 00:45, Al Viro wrote: > > if (beneath) { > path_put(&under); > read_seqlock_excl(&mount_lock); > + if (unlikely(!mnt_has_parent(m))) { > + read_sequnlock_excl(&mount_lock); > + return -EINVAL; > + } > under.mnt = mntget(&m->mnt_parent->mnt); > under.dentry = dget(m->mnt_mountpoint); > read_sequnlock_excl(&mount_lock); Well, *this* would look a lot cleaner with a "scoped_guard(mount_locked_reader)", but you didn't do that for some reason. Am I missing something? Linus