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 C3FF2C6FD1C for ; Sun, 26 Mar 2023 18:30:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229743AbjCZSaZ (ORCPT ); Sun, 26 Mar 2023 14:30:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229506AbjCZSaX (ORCPT ); Sun, 26 Mar 2023 14:30:23 -0400 Received: from mail-ed1-x534.google.com (mail-ed1-x534.google.com [IPv6:2a00:1450:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3432440E1 for ; Sun, 26 Mar 2023 11:30:22 -0700 (PDT) Received: by mail-ed1-x534.google.com with SMTP id h8so27129157ede.8 for ; Sun, 26 Mar 2023 11:30:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1679855420; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :from:to:cc:subject:date:message-id:reply-to; bh=63o6e5rEgX2IrN7zKM8V/sqYJ9KqMSs/8xneBhtemz8=; b=a+X09xb6Xg2LN0YE6I9dwWGx8Iydb5dVfBNXUu30YMTUCxvR/5sS9a6RlTOCSfCere jf/6+IFmH3c6oRMoc9MNi1+skC64nVUmkEoYe6+GgXK+MmTzEmAMqzbwrTOpt/g8rgTQ XMbXk4Ap6uLOSZ2Rc5UxK1RWweWeM5eXov3Ffccbw9j5voaKQUaAZEhduvLudHX+TXJQ fxwM/6T9hXCGSkaSIDVyFNvC+m7l+jekCGhYONWeqa50zsaJrm1tvmYw9Uw+1vbFF4FT 0lVZ3x551OxXQBTXbM5+fBeH8a46uoTSPr1dYH5bzYxYqEmjCrxzVEMU1F0/ED3Wdh99 Hp8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1679855420; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=63o6e5rEgX2IrN7zKM8V/sqYJ9KqMSs/8xneBhtemz8=; b=Gnxs+US08JIlgpfjNjIII9HbQIQNrzg3P2rTkFzL5cj8sSdKARYott1BRpyhIuGi/5 gUrs94H0OMgNR7Hhpi7ijjpuaFQeONhqGeNNSqjdu5XKqhOOa29lC2SCTCYmEKjI5Zao uWO6+nM/wDd4HaPYfeiWfRNzOWXwpTQTNO0dmMY5DYLSFrpyAs1qFbf07ZgFObycnvez x4BXBEKxLtL6NESukoQw1UIElpMdnd3t8RvK3d4JSOexN46zWmlrxaooCzHYOiqZg9zn 8JCLoQit/sosCJ5GGQv1VFoUOhcIAykncC6k56voB/GgD5lBWlh725j5oJFa6tAAKTf+ BvWw== X-Gm-Message-State: AAQBX9dfXc22vS1byfua5ysKkNJfUPS3sy1Eu2nsZ8Nrh35c7+KbhTaU GxItasK7xAKutUnZAUEM9Q== X-Google-Smtp-Source: AKy350YA8IN7Rquiu4eZ1pwnI/sPJvRbi8U+y6X0oCKABdKxueWbJ5wqn0w1uPz2D6X1hAsklJF7xw== X-Received: by 2002:a17:906:bcd1:b0:921:5cce:6599 with SMTP id lw17-20020a170906bcd100b009215cce6599mr10718283ejb.41.1679855420414; Sun, 26 Mar 2023 11:30:20 -0700 (PDT) Received: from p183 ([46.53.253.224]) by smtp.gmail.com with ESMTPSA id kx1-20020a170907774100b0091fdd2ee44bsm13149307ejc.197.2023.03.26.11.30.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 26 Mar 2023 11:30:20 -0700 (PDT) Date: Sun, 26 Mar 2023 21:30:18 +0300 From: Alexey Dobriyan To: Willy Tarreau Cc: Thomas =?utf-8?Q?Wei=C3=9Fschuh?= , "Paul E. McKenney" , linux-kernel@vger.kernel.org Subject: Re: [PATCH 6/8] tools/nolibc: tests: add test for -fstack-protector Message-ID: <89a960c7-0c9b-43ab-9fc8-a68405f7ed6a@p183> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Willy Tarreau wrote: > #if defined(__clang__) > __attribute__((optnone)) > #elif defined(__GNUC__) > __attribute__((optimize("O0"))) > #endif > static int smash_stack(void) > { > char buf[100]; > > for (size_t i = 0; i < 200; i++) > buf[i] = 'P'; > > return 1; > } If you want to corrupt the stack, corrupt the stack! asm( ".globl f\n" "f:\n" "movq $0, (%rsp)\n" "ret\n" ".type f,@function\n" ".size f,.-f" ); No problems with optimisation levels.