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 5422923F422; Fri, 19 Dec 2025 09:24:10 +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=1766136251; cv=none; b=eqKNX5tp1fJFHhqhcw3Jm7luOxe5TddGJHWIy4IvmJQjKuAV7tHdGUOqzSViQRFkDNYYm70H1JlQzMW+hUZ7ymd9QzMOKwN/XRbhv9lnySpMuSsrHfKLe34dMXlUEILXoerHYWcfwQ/NTsgSdhZqzCMUgbUBywTAaevpP2nGWuA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766136251; c=relaxed/simple; bh=Q7Tat+DlNEr9zwMi10HMp4z6C9OLetF7wpcLmG3Nr6o=; h=Date:From:To:CC:Subject:In-Reply-To:References:Message-ID: MIME-Version:Content-Type; b=FwQSafTfd4dalOHLti1/yWiRqvQEtkWVVY4jC+kPBn26kx8+zhnEw+TbZMOgx06ZCScPL5s2a0m3/5s/NAzloL53VO/Azgx406b0o8w8dvU/puJOdzUdE3iNC5KzEKGnnVqRYGerOMdxqPdDviNjb4jqxfFuvgsySGFve5GJnBU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iJeGBQSm; 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="iJeGBQSm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 57B4DC4CEF1; Fri, 19 Dec 2025 09:24:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1766136250; bh=Q7Tat+DlNEr9zwMi10HMp4z6C9OLetF7wpcLmG3Nr6o=; h=Date:From:To:CC:Subject:In-Reply-To:References:From; b=iJeGBQSmHJ7xw1ebYcMUv3OrvqEJD8ApYHkRX1ViM7KpcnS7B1rgP9tfs5oxhCWxG Rm4PC/W74o0ejiM5LppZqRSXCRA3mkvKrEqhBNHF71/01oLwgSlur+w8TiPru/pfNA u6gD2qSIkrLr/pl0EqJdTRIO8VIvSkp7K+EKwRy+3CX8K6jyknqpEOkcpvKCfSjXuU O7A015VxRzBIkWTt7M5mRFS65Q2fWGTO7PtKfATaKOMZ9P7oS7GZMVehzzLliUCnad dP+OOoFlqnFYcbQVr75YsMhKxRupFcTd8VU1IytrRfG1l56lCgntqqYmaXktA3+9wo TD0xhhbb/eLhg== Date: Fri, 19 Dec 2025 17:33:24 +0900 From: Kees Cook To: Tejun Heo , Chen Ridong CC: =?ISO-8859-1?Q?Michal_Koutn=FD?= , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, "Gustavo A. R. Silva" , Johannes Weiner , "Gustavo A. R. Silva" Subject: Re: [PATCH 3/4] cgroup: Use __counted_by for cgroup::ancestors User-Agent: K-9 Mail for Android In-Reply-To: References: <20251217162744.352391-1-mkoutny@suse.com> <20251217162744.352391-4-mkoutny@suse.com> <87cc0370-1924-4d33-bbf1-7fc2b03149e3@huaweicloud.com> Message-ID: <6387B54B-7524-4AB9-AB05-4AB529353EF4@kernel.org> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On December 19, 2025 1:09:42 AM GMT+09:00, Tejun Heo wro= te: >On Thu, Dec 18, 2025 at 03:09:32PM +0800, Chen Ridong wrote: >> Note that this level may already be used in existing BPF programs (e=2E= g=2E, >> tools/testing/selftests/bpf/progs/task_ls_uptr=2Ec)=2E Do we need to co= nsider compatibility here? > >That's a good point=2E Is __counted_by instrumentation tied to some compi= ler >flag? If so, might as well make it an optional extra field specifically f= or >the annotation rather than changing the meaning of an existing field=2E > >Thanks=2E > CONFIG_FORTIFY_SOURCE and CONFIG_UBSAN_BOUNDS use the information for inst= rumentation=2E --=20 Kees Cook