From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f169.google.com (mail-yw1-f169.google.com [209.85.128.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E29AA5D8E4; Tue, 23 Jan 2024 11:20:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706008831; cv=none; b=OeMmD7Lj+yJ9wqbKWKk2DDRi2BzahQEbojihDhecNK0FpU8uJKqghK5l0dQZlP/1wsLY7DiroVAJVWcU1cLFxDIqDgW+5HGKDRu8j3QI6yAQ6CoJzslAqX6Tx5eJgIxYT2aZjqoXAfNLphtxncGXGNHu+XWiUXjLn3AbHn16JBk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706008831; c=relaxed/simple; bh=IisEDnr+p0PvkSItO7KxH/POXpdIe2NGTC+4LQBQ9ps=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=WgRrQQW3TLCEq9/qHJBkonmPaadcc1zLvz3exRnNi30t5p3zhLc3QwVZCW9sTwIQaXoBDYUKaUnFlEALDHnOR7T5C3c5PB1bZtOAkY8tao1drY8tpyE1i566dcs/+XJ211bYcpHd+u8tbr0gbW/tFI4Myt+Pl+JLOjxqqy2ow4E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=kBijgEJP; arc=none smtp.client-ip=209.85.128.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kBijgEJP" Received: by mail-yw1-f169.google.com with SMTP id 00721157ae682-600094c5703so16494477b3.3; Tue, 23 Jan 2024 03:20:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1706008829; x=1706613629; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=IisEDnr+p0PvkSItO7KxH/POXpdIe2NGTC+4LQBQ9ps=; b=kBijgEJPME7gdEUt34NulXDmWBhtfdubuv50n9xk8hO13j5xgZDuQcVwWq/AJfF3QC wek2AoKoOqgKgQTpRFAgZytudOTE+E1LHSgy4W2HAS4zu7r2NRjcqizzFEebIammQuaD l//TZc85tTAs76+PoVHs5CRZntIkk3RlGYtRHcw69dhK/BffJ6X/OY0JZ1X9SPTwdyN2 NixzCiXvfzE5mbNNVRXtsTX/DTJmv7lN16q6Fc0WNKtvc1BLgHYusp4qhBbmrtCNUH8r lFArGNoVbr6ah+98iYgM6bX80JhxgZfLXGuleY3KtWGwsu/RcQ4DmJbUh11b8apApq4Z 2kGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706008829; x=1706613629; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=IisEDnr+p0PvkSItO7KxH/POXpdIe2NGTC+4LQBQ9ps=; b=RSZ2d6Uo5UKLulZSvKPT9nohgfBPN8a12lmUqg3hisIhYbKwatOm1yJSrsKF0fPTm2 q3dZkPAThkKuNoQa/jct7frk/I7n9RyXdpbKxgEgEh+gwzC9a+E7eRJvu51Z/ahtLllv vuWZJrMvdJr1nxTQZTdSiIMG34wOrcS93iHd+SycR7AbaV1DyYQLSeYS2Z2w8IqETkiK AeB7AXlK3OYAOHT2lBkNWaamUXyQFYTYNNVNX93tw/ZYLdAUbO5/x1ZR7g5TFkBqe9/B vAqfmsGu7j24q5fWjpC2R3lq396M1EmFfArTp1LqON7s7IxacsbfeXT8In5yMCuW9RAG Lw5w== X-Gm-Message-State: AOJu0YyGdV0IP13sn3viamDOI40hvYrFZvYxsuqkw9wvXL1jEOpCdo1D CiAxrNfST7wefsRxoU1qkgIlG2zhaQxVrnpeGc7wZjZDPdOggNnqgLwgt9YgwviU1+cBvs78my/ dTP/OD1wZNrgoqrA98NWRRnY6T0o= X-Google-Smtp-Source: AGHT+IH4IQpUe/K+u333LaknVexj1p6gtLA26l3nnEZTIeJfvnH371BjAwUrxox7EyMtb6d9YE7r9aefRN/hzusUOWg= X-Received: by 2002:a0d:d582:0:b0:5fb:d2da:63d1 with SMTP id x124-20020a0dd582000000b005fbd2da63d1mr4295362ywd.36.1706008828795; Tue, 23 Jan 2024 03:20:28 -0800 (PST) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20240122235208.work.748-kees@kernel.org> <20240123002814.1396804-6-keescook@chromium.org> <14B4D24C-4CBA-401E-8111-CF74482CA956@kernel.org> In-Reply-To: <14B4D24C-4CBA-401E-8111-CF74482CA956@kernel.org> From: Miguel Ojeda Date: Tue, 23 Jan 2024 12:20:17 +0100 Message-ID: Subject: Re: [PATCH 06/82] overflow: Reintroduce signed and unsigned overflow sanitizers To: Kees Cook Cc: Kees Cook , linux-hardening@vger.kernel.org, Justin Stitt , Miguel Ojeda , Nathan Chancellor , Nick Desaulniers , Peter Zijlstra , Marco Elver , Hao Luo , Przemek Kitszel , "Gustavo A. R. Silva" , Bill Wendling , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, Jan 23, 2024 at 5:45=E2=80=AFAM Kees Cook wrote: > > Yes. We removed this bad behavior by using -fno-strict-overflow, and we w= ill want to keep it enabled. Yeah, I only meant that the wording of the commit seems to say there is something special about the "overflowing behavior", i.e. I was expecting just UB with the usual implications, but given the extra text in the parenthesis, I wondered while reading it if there was something different/special going on. > The stack usage is separate. (This may even be fixed in modern Clang; thi= s comes from the original version of this Kconfig.) The not booting part is= separate and has not been tracked down yet. I see. Thanks! In any case, if the sentence means only 32-bit x86, users couldn't still see it. But since this was already in the revert now that I take a look, I guess ignore this :) > I wondered the same -- they were this way when they were removed, so I ju= st restored them as they were. :) Makes sense :) Cheers, Miguel