From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx4/GqxbZasF1cT44SpANULOHNpRseubJwHvE7ZWtZq523M/d2oU39H3JBbvIxNMWCQVlRTrC ARC-Seal: i=1; a=rsa-sha256; t=1524077428; cv=none; d=google.com; s=arc-20160816; b=CgRgEvb5MKmFDWj70yWNaE7AgIiYZnWom7XxUGZTMT+e4tr5Xf0J9gZDDl/pwQZlCu VaiyAdjusyZqYT9wMFB8c0zK/kPq5Hy3pkgnDcHOvNPTovdPhshCdIQ/5U0nsWpyqHoU FONTR1VSSMdXFLyMyZQmM+GhbsI8fh+tZygIv4QhveA5x4rpfVWO1NHDvhGD3PQnWpCh Libg6jJyspKeQxYvjyYW8OGYbOSO96MMHM2mgrrT2uvvoSfHv/LyLGxUPy+3Tvjy/dYE sQVF7srnfasBQEYxydXIsWqHACj8YjzV7wxsOcIA+fPAOUYknblkjyawmF6UfzMVm0f2 vrlQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=content-transfer-encoding:content-language:in-reply-to:mime-version :user-agent:date:message-id:from:cc:references:to:subject :arc-authentication-results; bh=GCghOTnMMwFlRzWZr7vZwFIgmcMzyOxbLTCatbIzpAI=; b=OA0qwXlVCiLFfzr5+OqwVq4rPqCMf8WNwOq+FM4h9GUGIRRJNd1wYmLNFdygEFyVIp IVILA3pExfVYHrYh2K/7iI85r+Cq9oltbaIyIUQ/q4sz/aB4GF6r/JzQ++T1X/9SWf7x AIrFdbe3joV4WoEm/r0jXoCgNeX/ILHPCQeFNrcBv9KqH0XewIi7ZKVNcc8OLJyuk6mF 2oesZTClvbLVcdpQ4DVdJum2ymhzBhGWrSWOEy+jShRJ+eQlW1RaQxS0FTjHH2Iqohe2 wa+h5uyTPhXbp8CpAIZNGib4ELFU35U/2TefTb+Mx2h6NDhzEEm+ywyjie/I19BPOov8 iNXA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of dave.hansen@linux.intel.com designates 192.55.52.88 as permitted sender) smtp.mailfrom=dave.hansen@linux.intel.com Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of dave.hansen@linux.intel.com designates 192.55.52.88 as permitted sender) smtp.mailfrom=dave.hansen@linux.intel.com X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,466,1517904000"; d="scan'208";a="34391495" Subject: Re: [PATCH v11 2/6] x86/entry: Add STACKLEAK erasing the kernel stack at the end of syscalls To: Kees Cook , Alexander Popov , Ingo Molnar , Laura Abbott , Linus Torvalds References: <1523024546-6150-1-git-send-email-alex.popov@linux.com> <1523024546-6150-3-git-send-email-alex.popov@linux.com> Cc: Kernel Hardening , PaX Team , Brad Spengler , Andy Lutomirski , Tycho Andersen , Mark Rutland , Ard Biesheuvel , Borislav Petkov , Richard Sandiford , Thomas Gleixner , "H . Peter Anvin" , Peter Zijlstra , "Dmitry V . Levin" , Emese Revfy , Jonathan Corbet , Andrey Ryabinin , "Kirill A . Shutemov" , Thomas Garnier , Andrew Morton , Alexei Starovoitov , Josef Bacik , Masami Hiramatsu , Nicholas Piggin , Al Viro , "David S . Miller" , Ding Tianhong , David Woodhouse , Josh Poimboeuf , Steven Rostedt , Dominik Brodowski , Juergen Gross , Greg Kroah-Hartman , Dan Williams , Mathias Krause , Vikas Shivappa , Kyle Huey , Dmitry Safonov , Will Deacon , Arnd Bergmann , Florian Weimer , Boris Lukashev , X86 ML , LKML From: Dave Hansen Message-ID: Date: Wed, 18 Apr 2018 11:50:25 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1597007022879408472?= X-GMAIL-MSGID: =?utf-8?q?1598111014287950524?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On 04/16/2018 11:29 AM, Kees Cook wrote: > Dave, Ingo, Linus: how does this look? With the assembly rewritten > into C, the entry changes are very small: The assembly looks very nice to me now. It is as minimally invasive as it can get. Definitely no objections from me on that part.