From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 498AC2222D2; Tue, 24 Jun 2025 17:37:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750786669; cv=none; b=t0OoCVeKblDgfs1F1tkbgV5h4OqTb/iKmfX9k3qSY6MojgmiQooDbgQMUAe6dk1Gp/wrAadIW4MHKLDThSFlbLk+90E9kzz0wVLw+3VCXiycXKLrgv+RrnGTBOv6NIQjTeeJ9sS9/ARVMuly0Ot4gGlk3vRpJ97XsZF2WI5kklE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750786669; c=relaxed/simple; bh=a5PVovFsmpphhcC1hWSRAtIoVL1Eo6VMJ/WYND+fSEw=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=qsMysS9km7xlg149r+sYW+D1bl8lvihjsUbH+MStAGXwnV9jk92LTETjqOM5/bzmjUBEQkZfoZcSrAiaa2vXSd+xmEF7/y6Zg+0fkWhvmUxb4QnPbMc30AxPMXY1l4gRIwiNOWBt4+H/aTB0Zw2xh6Z/YpGcQz8BdXe51m6/5U4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c8cGsNaW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="c8cGsNaW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1DFD0C4CEE3; Tue, 24 Jun 2025 17:37:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750786669; bh=a5PVovFsmpphhcC1hWSRAtIoVL1Eo6VMJ/WYND+fSEw=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=c8cGsNaWX0fVjLDqhSwlSne+Kyd6+LJLh5qhacvj0X6mFJuLHg+C9m57qwBDPRfZ3 rqgygKXQcSa/x8Z75ECE7OZGL/yiYeNeMAX3s3gg5dN1YHTOR9YSKLshkHmVGLCoy/ YgeZ+O1sPAsxMhBNsKJzquiGANTOfxaaPdDYEAubc0U4uUYsetpWRhk6Vil6T0Lj91 cOfdKwHFltAJrMDKXsZ9oqoOGvqz1gc4oU4EacJjUgt7NTZQRAd1UdZybzZ0+TXoEP BJGw9DylKyBS87f6VgKEH4N7rAdsX7OdTvPEO1ArkGcnuT4GDyeInsvI9X6FYMK9Hi m+oqoCGQTKZAQ== Received: by mail-qt1-f171.google.com with SMTP id d75a77b69052e-4a43afb04a7so40811221cf.0; Tue, 24 Jun 2025 10:37:49 -0700 (PDT) X-Forwarded-Encrypted: i=1; AJvYcCVvjUQ5kZ28r6/9dwx2ZN+3psXNwe5oxrUhGI+AjGLjePHIOD8bj6A1cr/r9Xu/TqzvSeBlhE/OU66QtN9/@vger.kernel.org, AJvYcCVvlB9qBoor/XRDUMwI+Q3peEaiA+TfNymgYpDN1AUvsOvMTA2lO5jAYOdnpOeUom1Wo0SrDFC0Y0t4o5QdCG+xn0qneZoL@vger.kernel.org, AJvYcCXiGYVc4gXZk93ADE1g/Fz1Ucvl6BnYjK+9cOd+1LJTNmJx/LN5lZ1fZTNMVcURVfiAj7woGCzKihopWUFb@vger.kernel.org X-Gm-Message-State: AOJu0YxrtIohEGsYHfsCXxVRcaekKbEet5gMBl2f/J03UM4hX0uGI31x uSqKm3gbDq5NIOZeEXrcNpqlga/Y3eA7c80i+M4Bm0hdJoZwNslDBPkLQxmo9Elbc21iPrRgoYN Y6hOUPMSSow3aC0ds19bKmaQn9kppClI= X-Google-Smtp-Source: AGHT+IHrLg1ZHp9UwVuJJHNbLnUi5fWv+f+FjuAnJJGFt+bl5ul6NjqhpyEZp+PcNDwB+wrEAEizIr5VdXAFoiU6IZY= X-Received: by 2002:a05:622a:1310:b0:4a7:146b:c5e5 with SMTP id d75a77b69052e-4a7c06cbaf9mr3336251cf.21.1750786668241; Tue, 24 Jun 2025 10:37:48 -0700 (PDT) Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20250617061116.3681325-1-song@kernel.org> <20250617061116.3681325-2-song@kernel.org> In-Reply-To: From: Song Liu Date: Tue, 24 Jun 2025 10:37:36 -0700 X-Gmail-Original-Message-ID: X-Gm-Features: AX0GCFtrQZFESJoWau6EG2iZopaA5_plWDAcACcPjqKr1AYhYf7Gc2RQxxN8qhg Message-ID: Subject: Re: [PATCH v5 bpf-next 1/5] namei: Introduce new helper function path_walk_parent() To: Jan Kara Cc: bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, kernel-team@meta.com, andrii@kernel.org, eddyz87@gmail.com, ast@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, viro@zeniv.linux.org.uk, brauner@kernel.org, kpsingh@kernel.org, mattbobrowski@google.com, m@maowtm.org, neil@brown.name Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Jan, On Tue, Jun 24, 2025 at 5:18=E2=80=AFAM Jan Kara wrote: > > On Mon 16-06-25 23:11:12, Song Liu wrote: > > This helper walks an input path to its parent. Logic are added to handl= e > > walking across mount tree. > > > > This will be used by landlock, and BPF LSM. > > > > Suggested-by: Neil Brown > > Signed-off-by: Song Liu > > Looks good to me. Feel free to add: > > Reviewed-by: Jan Kara Thanks for the review! [...] > > + * > > + * Returns: either an ERR_PTR() or the chosen parent which will have h= ad > > + * the refcount incremented. > > + */ > > The behavior with LOOKUP_NO_XDEV is kind of odd (not your fault) and > interestingly I wasn't able to find a place that would depend on the path > being updated in that case. So either I'm missing some subtle detail (qui= te > possible) or we can clean that up in the future. We have RESOLVE_NO_XDEV in uapi/linux/openat2.h, so I guess we cannot really remove it? Thanks, Song [...]