From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 3ED1337C81 for ; Fri, 27 Oct 2023 15:50:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="G9PlaRf1" Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CA0C810A for ; Fri, 27 Oct 2023 08:50:46 -0700 (PDT) Received: by mail-pf1-x42b.google.com with SMTP id d2e1a72fcca58-6bd73395bceso1636712b3a.0 for ; Fri, 27 Oct 2023 08:50:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1698421846; x=1699026646; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=3XAYQa3ufeYpImNNDp7qPpU7hHfY982hDiKyd9DINVw=; b=G9PlaRf190e9ZoCeBEdFIcQvKCnRCcxb3iXxMOzH7hNkn6yW6sDMMuraO/1+2BP8Cd nv54el58uu6RQ0M4gJNHUKP2zUAFtTA1+HhTRsbN6Ok1TbuQDfgaWlhlQCtLwlpKjWqs ByTR4qOuW5J5lFsZIxElNvRqwsy2ti76Z7avQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698421846; x=1699026646; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=3XAYQa3ufeYpImNNDp7qPpU7hHfY982hDiKyd9DINVw=; b=dHgVHZoeeKdxcWTfRzhaCSvfBZtaOFexYP7y1M385h/YFrbpEqBEGczKLLtkQegoU4 Us7YiwixQkhBeTdbiCkp02wYsQDHss4NIU/h63yrBp+A+79tHDQI7gWSV9Hx4FsnWBo8 rP2DDBDaYa1YVPhWV3Vl0dOUVJ//DDaUu2wI6plyxMueuC6PJBDVzFn/xFB16ETRXAhs ebIwr4poz2oqYKyHdvSUkRMCytmQZN14iFgVLsdUVo7r8XREMIdJtoX49KYtv5DhDt7E VAde2+P9feRf/0YX7NCVskNOis4QK91m7wXlQo4n/klsyYx1cBiNMgxI5lDVHFakZFwU LDyQ== X-Gm-Message-State: AOJu0YxAm4lFLZuWFnl6PUhpriCp97O/qkEyDaNb/xMw8x/zlt/P+jRS yEG5eFcKnaAN1XRAQzle+kk25w== X-Google-Smtp-Source: AGHT+IHLDmn+AjLaF61rtsmuDfAYVnkIvtlWqCwVQhYl6dmEc/RCPXxVQIOdEbbpEEe95zK+/gUeVw== X-Received: by 2002:a05:6a00:28c9:b0:6b3:80f8:7e91 with SMTP id ci9-20020a056a0028c900b006b380f87e91mr6843699pfb.9.1698421846306; Fri, 27 Oct 2023 08:50:46 -0700 (PDT) Received: from www.outflux.net (198-0-35-241-static.hfc.comcastbusiness.net. [198.0.35.241]) by smtp.gmail.com with ESMTPSA id h15-20020a63384f000000b0056c2f1a2f6bsm1249776pgn.41.2023.10.27.08.50.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Oct 2023 08:50:45 -0700 (PDT) Date: Fri, 27 Oct 2023 08:50:45 -0700 From: Kees Cook To: Christoph Hellwig Cc: Steven Rostedt , "Matthew Wilcox (Oracle)" , Justin Stitt , Kent Overstreet , Petr Mladek , Andy Shevchenko , Rasmus Villemoes , Sergey Senozhatsky , Masami Hiramatsu , Greg Kroah-Hartman , Arnd Bergmann , Jonathan Corbet , Yun Zhou , Jacob Keller , Zhen Lei , linux-trace-kernel@vger.kernel.org, Yosry Ahmed , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH v2] seq_buf: Introduce DECLARE_SEQ_BUF and seq_buf_str() Message-ID: <202310270849.14B83B56D@keescook> References: <20231026194033.it.702-kees@kernel.org> <20231027045451.GA7838@lst.de> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231027045451.GA7838@lst.de> On Fri, Oct 27, 2023 at 06:54:51AM +0200, Christoph Hellwig wrote: > On Thu, Oct 26, 2023 at 12:40:37PM -0700, Kees Cook wrote: > > Solve two ergonomic issues with struct seq_buf; > > > > 1) Too much boilerplate is required to initialize: > > > > struct seq_buf s; > > char buf[32]; > > > > seq_buf_init(s, buf, sizeof(buf)); > > > > Instead, we can build this directly on the stack. Provide > > DECLARE_SEQ_BUF() macro to do this: > > > > DECLARE_SEQ_BUF(s, 32); > > DECLARE_SEQ_BUF_ONSTACK maybe? But otherwise this looks like a good > concept. It's usable for globals too... also it's a shorter name as-is. :) -- Kees Cook