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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 152CAC432C1 for ; Tue, 24 Sep 2019 16:22:33 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 596D220872 for ; Tue, 24 Sep 2019 16:22:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="O8zGPIRb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 596D220872 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-16928-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 22370 invoked by uid 550); 24 Sep 2019 16:22:24 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 22335 invoked from network); 24 Sep 2019 16:22:24 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=B/ALc/qTcQ4k/eCkDMCHCUlzu+44O0snaF71bHOvSBA=; b=O8zGPIRb6udzS8CeK12mIGTdihD/nbhSG3mye5euKo6yGM6boWQd3/J/ShzdWlhmUH 3WBrBWZeqFa1y+iW4YT406eldU8YVPHi9w8OUNYhOwaDdqYG3u4b8q66J2P2/ebkbu6N JcQboVDtKw2Zwq/BUkz4IQOCXLe8MqkKZ++0w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=B/ALc/qTcQ4k/eCkDMCHCUlzu+44O0snaF71bHOvSBA=; b=qfxloSjhFDbZxp4a+9p6C9It9zC428AI++2XTu/iUy+h/UMXrxCCe5txMUfuQ/dt/g rvA5dxYi4MFLxiDFdy0QtU9sVx7HeD+0vwPgSq/ChdzKgTClSpMHSwpR0S4QP0NVh/gN 5UzCDngYpwbpO+gKJ3HVZW7bsiJJfNadMGtJarfU14/cQhMvzf9H8q8U9gDVj5Zk0Lnp xog1vBB5P+IeA/rKW9NTzPrOeEM6sA8lLbtHK8v4STvWnQCQxvSrZXEFAYPdA50wVy+O kxgsVCWHTmXniJ4cJdpkwZI/92XhqJYe4CaNSmbMv1vtYkNoxMY10bFOc142tYO8Jpea UJAQ== X-Gm-Message-State: APjAAAXKNioBz8NB6Ig7WQJ1pI0RUH1WulbyNAtvIIfN7cnz3XyBLfSa nXJqdyqZ9p2PDu719yx78tKb0g== X-Google-Smtp-Source: APXvYqz6f0NZvQy5yYrKu6cts+T4A5fOIBUPykaVdTiHtcZ+MGdIGC42Mo2ufzIwEq03ic6ykQZRoA== X-Received: by 2002:a17:90a:b012:: with SMTP id x18mr966430pjq.118.1569342132377; Tue, 24 Sep 2019 09:22:12 -0700 (PDT) Date: Tue, 24 Sep 2019 09:22:10 -0700 From: Kees Cook To: Pankaj Bharadiya Cc: pankaj.bharadiya@gmail.com, andriy.shevchenko@linux.intel.com, kernel-hardening@lists.openwall.com, akpm@linux-foundation.org, mayhs11saini@gmail.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/5] linux/kernel.h: Add sizeof_member macro Message-ID: <201909240920.AE3CD67E87@keescook> References: <20190924105839.110713-1-pankaj.laxminarayan.bharadiya@intel.com> <20190924105839.110713-2-pankaj.laxminarayan.bharadiya@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190924105839.110713-2-pankaj.laxminarayan.bharadiya@intel.com> On Tue, Sep 24, 2019 at 04:28:35PM +0530, Pankaj Bharadiya wrote: > At present we have 3 different macros to calculate the size of a > member of a struct: > - SIZEOF_FIELD > - FIELD_SIZEOF > - sizeof_field > > To bring uniformity in entire kernel source tree let's add > sizeof_member macro. > > Replace all occurrences of above 3 macro's with sizeof_member in > future patches. > > Signed-off-by: Pankaj Bharadiya > --- > include/linux/kernel.h | 9 +++++++++ > 1 file changed, 9 insertions(+) Since stddef.h ends up needing this macro, and kernel.h includes stddef.h, why not put this macro in stddef.h instead? Then the open-coded version of it in stddef (your last patch) can use sizeof_member()? Otherwise, yes, looks good. (Though I might re-order the patches so the last patch is the tree-wide swap -- then you don't need the exclusions, I think?) -Kees > > diff --git a/include/linux/kernel.h b/include/linux/kernel.h > index 4fa360a13c1e..0b80d8bb3978 100644 > --- a/include/linux/kernel.h > +++ b/include/linux/kernel.h > @@ -79,6 +79,15 @@ > */ > #define round_down(x, y) ((x) & ~__round_mask(x, y)) > > +/** > + * sizeof_member - get the size of a struct's member > + * @T: the target struct > + * @m: the target struct's member > + * Return: the size of @m in the struct definition without having a > + * declared instance of @T. > + */ > +#define sizeof_member(T, m) (sizeof(((T *)0)->m)) > + > /** > * FIELD_SIZEOF - get the size of a struct's field > * @t: the target struct > -- > 2.17.1 > -- Kees Cook