From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 682FBC43217 for ; Wed, 16 Nov 2022 08:14:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238647AbiKPIOK (ORCPT ); Wed, 16 Nov 2022 03:14:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233167AbiKPINr (ORCPT ); Wed, 16 Nov 2022 03:13:47 -0500 Received: from frasgout12.his.huawei.com (frasgout12.his.huawei.com [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E08D1054D; Wed, 16 Nov 2022 00:11:54 -0800 (PST) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4NBwbF2qvFz9v7Yf; Wed, 16 Nov 2022 16:05:45 +0800 (CST) Received: from roberto-ThinkStation-P620 (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwBnUm8mm3RjHPlrAA--.18293S2; Wed, 16 Nov 2022 09:11:29 +0100 (CET) Message-ID: <83cbff40f16a46e733a877d499b904cdf06949b6.camel@huaweicloud.com> Subject: Re: [RFC][PATCH 3/4] lsm: Redefine LSM_HOOK() macro to add return value flags as argument From: Roberto Sassu To: Paul Moore Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, revest@chromium.org, jackmanb@chromium.org, jmorris@namei.org, serge@hallyn.com, bpf@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Roberto Sassu , stable@vger.kernel.org Date: Wed, 16 Nov 2022 09:11:15 +0100 In-Reply-To: References: <20221115175652.3836811-1-roberto.sassu@huaweicloud.com> <20221115175652.3836811-4-roberto.sassu@huaweicloud.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.5-0ubuntu1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-CM-TRANSID: LxC2BwBnUm8mm3RjHPlrAA--.18293S2 X-Coremail-Antispam: 1UD129KBjvJXoW7KFWDWryxKr4fJrWxCr15Jwb_yoW8WryrpF 43ta4YkFnYvr47C3ZxWF1fC34rJ393Wr15trnrXw1Fva42yrnxK34kua1S9Fy09rWIkr1Y krWagry5Kw1DArDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUk0b4IE77IF4wAFF20E14v26ryj6rWUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I 0E14v26r4j6r4UJwAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG 6I80ewAv7VC0I7IYx2IY67AKxVWUXVWUAwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFV Cjc4AY6r1j6r4UM4x0Y48IcVAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7MxAIw28IcxkI 7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxV Cjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x0EwIxGrwCI42IY 6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1lIxAIcV CF04k26cxKx2IYs7xG6Fyj6rWUJwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv 6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxUrWlkDUUUU X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgASBF1jj4F8dQABss X-CFilter-Loop: Reflected Precedence: bulk List-ID: On Tue, 2022-11-15 at 21:27 -0500, Paul Moore wrote: > On Tue, Nov 15, 2022 at 12:58 PM Roberto Sassu > wrote: > > From: Roberto Sassu > > > > Define four return value flags (LSM_RET_NEG, LSM_RET_ZERO, LSM_RET_ONE, > > LSM_RET_GT_ONE), one for each interval of interest (< 0, = 0, = 1, > 1). > > > > Redefine the LSM_HOOK() macro to add return value flags as argument, and > > set the correct flags for each LSM hook. > > > > Implementors of new LSM hooks should do the same as well. > > > > Cc: stable@vger.kernel.org # 5.7.x > > Fixes: 9d3fdea789c8 ("bpf: lsm: Provide attachment points for BPF LSM programs") > > Signed-off-by: Roberto Sassu > > --- > > include/linux/bpf_lsm.h | 2 +- > > include/linux/lsm_hook_defs.h | 779 ++++++++++++++++++++-------------- > > include/linux/lsm_hooks.h | 9 +- > > kernel/bpf/bpf_lsm.c | 5 +- > > security/bpf/hooks.c | 2 +- > > security/security.c | 4 +- > > 6 files changed, 466 insertions(+), 335 deletions(-) > > Just a quick note here that even if we wanted to do something like > this, it is absolutely not -stable kernel material. No way. I was unsure about that. We need a proper fix for this issue that needs to be backported to some kernels. I saw this more like a dependency. But I agree with you that it would be unlikely that this patch is applied to stable kernels. For stable kernels, what it would be the proper way? We still need to maintain an allow list of functions that allow a positive return value, at least. Should it be in the eBPF code only? Thanks Roberto