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=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 18CD8CA9ECF for ; Fri, 1 Nov 2019 22:36:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CCE5E21A4A for ; Fri, 1 Nov 2019 22:36:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Bli3xmuB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727626AbfKAWgT (ORCPT ); Fri, 1 Nov 2019 18:36:19 -0400 Received: from mail-lj1-f196.google.com ([209.85.208.196]:38016 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726230AbfKAWgT (ORCPT ); Fri, 1 Nov 2019 18:36:19 -0400 Received: by mail-lj1-f196.google.com with SMTP id y23so11326462ljc.5 for ; Fri, 01 Nov 2019 15:36:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=VOVEnixRZLxQkCHgEpMJYKVl9naG8q4Bhsey3a4BJyw=; b=Bli3xmuBt9/GwnfhQ+WLZeBpC+LGylrKEihKmG9wDJcaF6w3L/ZQ8vt3GI4YPWXFJQ 5Om7iCdkbv/lP18+LV92eRVs401olXcWreQAxfwPfepVtiVSDh9+nHAn2/3d+gfz9UVm yMWAVezWZJNqsbBLHANyYxJW6QpG5vniX1o53MF1dl5bc0zwLsqDDWKMYaMNZ47JDbyE v0XCStgcgsGwANfNW7O2l7MqWzWiGoQksAS9QIjgoVFUAhEy6735xDLs92DbjUK8gYCH q+fHcZwm6Ytrc4SrW8PPtsChFVdCSMaGofeTewgiaGn6jHXy73Odpndaqn2pcpxNkMKy K1qA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=VOVEnixRZLxQkCHgEpMJYKVl9naG8q4Bhsey3a4BJyw=; b=tvRPMcUo7ejiJ9Nivj2csyOE9EIrBhbYppj2/YwOf0jqu8r3clD6iZ6DLs+ZoQF5uS vYdYHOR5VHFe/LnsGHyalrPQSi0gPrK5uD+6KcOUYrDJ5TGcba3kWkzzhwusv8HzRuec bU1b3JIf7GlRuPSqqcOUMyUuXXZ6jj+omr+mZU10jjMNOV94IfqXZ0DWgjC1FBEChZP3 cPnQlQxVO9yx3X8tK34mGspdU8nblSWSwuP4DD9eZNxhVrK76dy8M4zJcqhoyjPQb5+l e7oGegGxrXRPvIyP/9CJzXs3GOUO9kHJUctZ0CtbqSerHwh71iNq4O6DvmaIu8R0vANf 9M2g== X-Gm-Message-State: APjAAAUxR1SUKZQ5NkZfpEwTTQU6Wr4zjpkJ75TkXwZe05AjBAXb1JnS 1cV3VI5C/pdfsO1CUI/ioy9eck9fEf4PZD6KQLc= X-Google-Smtp-Source: APXvYqy3a3LpygwD50Ud81Z6exZF+LaVqLS3Tw+hEBAZP5UzR+Yt5u6jie3UaWjeMgSpzygcRllXXMsmSmfSgwH5eE4= X-Received: by 2002:a2e:8852:: with SMTP id z18mr9873721ljj.230.1572647776833; Fri, 01 Nov 2019 15:36:16 -0700 (PDT) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191101221150.116536-1-samitolvanen@google.com> <20191101221150.116536-6-samitolvanen@google.com> In-Reply-To: <20191101221150.116536-6-samitolvanen@google.com> From: Miguel Ojeda Date: Fri, 1 Nov 2019 23:36:05 +0100 Message-ID: Subject: Re: [PATCH v4 05/17] add support for Clang's Shadow Call Stack (SCS) To: Sami Tolvanen Cc: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Marc Zyngier , Nick Desaulniers , Jann Horn , Masahiro Yamada , clang-built-linux , Kernel Hardening , Linux ARM , linux-kernel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 1, 2019 at 11:12 PM Sami Tolvanen wrote: > > This change adds generic support for Clang's Shadow Call Stack, > which uses a shadow stack to protect return addresses from being > overwritten by an attacker. Details are available here: > > https://clang.llvm.org/docs/ShadowCallStack.html > > Note that security guarantees in the kernel differ from the > ones documented for user space. The kernel must store addresses > of shadow stacks used by other tasks and interrupt handlers in > memory, which means an attacker capable reading and writing > arbitrary memory may be able to locate them and hijack control > flow by modifying shadow stacks that are not currently in use. > > Signed-off-by: Sami Tolvanen > Reviewed-by: Kees Cook Reviewed-by: Miguel Ojeda Cheers, Miguel 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=-3.7 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 B89D9CA9ECF for ; Fri, 1 Nov 2019 22:36:25 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8ADFE217D9 for ; 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Fri, 01 Nov 2019 15:36:16 -0700 (PDT) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191101221150.116536-1-samitolvanen@google.com> <20191101221150.116536-6-samitolvanen@google.com> In-Reply-To: <20191101221150.116536-6-samitolvanen@google.com> From: Miguel Ojeda Date: Fri, 1 Nov 2019 23:36:05 +0100 Message-ID: Subject: Re: [PATCH v4 05/17] add support for Clang's Shadow Call Stack (SCS) To: Sami Tolvanen X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191101_153622_261634_5FD26FEF X-CRM114-Status: GOOD ( 12.08 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kees Cook , Ard Biesheuvel , Catalin Marinas , Jann Horn , Nick Desaulniers , linux-kernel , Steven Rostedt , Masahiro Yamada , clang-built-linux , Masami Hiramatsu , Marc Zyngier , Kernel Hardening , Laura Abbott , Will Deacon , Dave Martin , Linux ARM Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Nov 1, 2019 at 11:12 PM Sami Tolvanen wrote: > > This change adds generic support for Clang's Shadow Call Stack, > which uses a shadow stack to protect return addresses from being > overwritten by an attacker. Details are available here: > > https://clang.llvm.org/docs/ShadowCallStack.html > > Note that security guarantees in the kernel differ from the > ones documented for user space. The kernel must store addresses > of shadow stacks used by other tasks and interrupt handlers in > memory, which means an attacker capable reading and writing > arbitrary memory may be able to locate them and hijack control > flow by modifying shadow stacks that are not currently in use. > > Signed-off-by: Sami Tolvanen > Reviewed-by: Kees Cook Reviewed-by: Miguel Ojeda Cheers, Miguel _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 23C43CA9ECF for ; Fri, 1 Nov 2019 22:36:35 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 6DC57217D9 for ; Fri, 1 Nov 2019 22:36:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Bli3xmuB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6DC57217D9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17249-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 30044 invoked by uid 550); 1 Nov 2019 22:36:28 -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 30024 invoked from network); 1 Nov 2019 22:36:28 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=VOVEnixRZLxQkCHgEpMJYKVl9naG8q4Bhsey3a4BJyw=; b=Bli3xmuBt9/GwnfhQ+WLZeBpC+LGylrKEihKmG9wDJcaF6w3L/ZQ8vt3GI4YPWXFJQ 5Om7iCdkbv/lP18+LV92eRVs401olXcWreQAxfwPfepVtiVSDh9+nHAn2/3d+gfz9UVm yMWAVezWZJNqsbBLHANyYxJW6QpG5vniX1o53MF1dl5bc0zwLsqDDWKMYaMNZ47JDbyE v0XCStgcgsGwANfNW7O2l7MqWzWiGoQksAS9QIjgoVFUAhEy6735xDLs92DbjUK8gYCH q+fHcZwm6Ytrc4SrW8PPtsChFVdCSMaGofeTewgiaGn6jHXy73Odpndaqn2pcpxNkMKy K1qA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=VOVEnixRZLxQkCHgEpMJYKVl9naG8q4Bhsey3a4BJyw=; b=psL9f3qhp6ZirO81wBCPR9JzyKNRqfYybz4SdYOkl3k20VU0zAOPusr4VeYvaR3mV2 zkRz/HmGVvvjEbtGypCZ5PrlU2B7YdrqxOllDDTuJQv93XVzJUsS6JROuD48oQYy2PDG uGw0him6pd6C7P6dlwAlrxFrBB0tlQ8gueb6yEUlkcVEyv6TxM0WOqyhb+OdKWXVS+Pw 4OMi2yFuL1JqzUojUl2EDBWyNezn7U8CO34dU/k8s4ux5rlT0zimGXEL2vzWOAs0yocX LounRS+502mShob3iQIvdlheuHfeGDCYSMU4XswmkW3V3+6bbP8nyP6jflm35J8K0kz7 EIwg== X-Gm-Message-State: APjAAAWPnyFB00BS3LHY6fGjxEl+3uNQlwmCWJhjw80dkFaH2Bl8H43c whDq4+sMuxUKMhTDifFkpKDkyOsjWaNl2Jsm3Do= X-Google-Smtp-Source: APXvYqy3a3LpygwD50Ud81Z6exZF+LaVqLS3Tw+hEBAZP5UzR+Yt5u6jie3UaWjeMgSpzygcRllXXMsmSmfSgwH5eE4= X-Received: by 2002:a2e:8852:: with SMTP id z18mr9873721ljj.230.1572647776833; Fri, 01 Nov 2019 15:36:16 -0700 (PDT) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191101221150.116536-1-samitolvanen@google.com> <20191101221150.116536-6-samitolvanen@google.com> In-Reply-To: <20191101221150.116536-6-samitolvanen@google.com> From: Miguel Ojeda Date: Fri, 1 Nov 2019 23:36:05 +0100 Message-ID: Subject: Re: [PATCH v4 05/17] add support for Clang's Shadow Call Stack (SCS) To: Sami Tolvanen Cc: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Marc Zyngier , Nick Desaulniers , Jann Horn , Masahiro Yamada , clang-built-linux , Kernel Hardening , Linux ARM , linux-kernel Content-Type: text/plain; charset="UTF-8" On Fri, Nov 1, 2019 at 11:12 PM Sami Tolvanen wrote: > > This change adds generic support for Clang's Shadow Call Stack, > which uses a shadow stack to protect return addresses from being > overwritten by an attacker. Details are available here: > > https://clang.llvm.org/docs/ShadowCallStack.html > > Note that security guarantees in the kernel differ from the > ones documented for user space. The kernel must store addresses > of shadow stacks used by other tasks and interrupt handlers in > memory, which means an attacker capable reading and writing > arbitrary memory may be able to locate them and hijack control > flow by modifying shadow stacks that are not currently in use. > > Signed-off-by: Sami Tolvanen > Reviewed-by: Kees Cook Reviewed-by: Miguel Ojeda Cheers, Miguel