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=-9.7 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 46536C5DF60 for ; Tue, 5 Nov 2019 23:58:59 +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 C0576206B8 for ; Tue, 5 Nov 2019 23:58:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="uO/1FAWF"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="jWGQrW7g" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C0576206B8 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:To:From:Subject:References:Mime-Version :Message-Id:In-Reply-To:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ouav4OqpqthsNR1kqp2/EerXc25lrd15w+uP7AERr/I=; b=uO/1FAWFrPivB1 6Tx0WgJ9GsL3iw3wNQqbS4R24qq5Sm4Pi5eVuQ0EC1EqQtdgDBl/i+rLrgAsMISjuvMOHJxLiF8Mu WZfPXVD4OX3ptSFHImhRB/hjjbenJ8AxvnZIHWNIJsyN3bnMCP2RPSCSRUt9HsjpdcBfShuHyeKD9 BImml9A10ml1CtmOgDN0mBVgKJHZEtkTQPx+S1lAtZ4qBDUj34tQlv4zrEZipbVNp7ai7VWyo7muk WLce0e4AFCM+wQGhOd0NUIAf6qcD/NRGdG9i5G5kTbRl+iZRnV5bIz8AwnWuSH92Zlzjgvawr1T2v VoVWmfGAxIVBcaVcAGUA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iS8iv-0001sd-9E; Tue, 05 Nov 2019 23:58:57 +0000 Received: from mail-pl1-x64a.google.com ([2607:f8b0:4864:20::64a]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iS8gn-00085O-Cu for linux-arm-kernel@lists.infradead.org; Tue, 05 Nov 2019 23:56:47 +0000 Received: by mail-pl1-x64a.google.com with SMTP id k8so5358293plt.7 for ; Tue, 05 Nov 2019 15:56:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=uzQ8cGBP/iiy1dmy29qxsrkA2y8A3VyyoGWk/X1qxUc=; b=jWGQrW7gYc6D9nJteHiWYUXaoKd47FGvgCnUcq1RN0FNUvS12DXoQv/Qs2ZSsEmdsr KIrZA7BzUYt42AyztGMVcz/QumFEYK2cJY5/FcPWOE01nPlBEr1XYQMmzvlCuOtePFHy BrO2pUitDMPbbMwQ+djW4zvLYrFatsGxSZFpwthI0l0tEUjCd15qBB7CofGFXzjONnIJ qdmdd/w16M48KK0143WbpUnJCYAPG0RUwEwhRL4ts3yhMXpE4SQA62x4WivBRaT/AZDF 1NajHEvW01XhI1VvxrXdeiyPREGJ54AL4BUaLlFQCeTXTsDjryTGcoQgi5Pmte9ZuS+r +4hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=uzQ8cGBP/iiy1dmy29qxsrkA2y8A3VyyoGWk/X1qxUc=; b=AYChcfEdp3Lp6D8aHGjTJQOAaWRq13QyvJd0iRvYhktJTY0G7d/u5Fmya9WRS6LUCk +SHhywMJrHa5INJrHZrAnk4kN4cM9gZaEDYXntIQjpC/LlVvqmYa6j91tN+TNbFY5Ixn XlZAuddppmJCceQ8irEitI3HF1/W3N4g1gS1liVFzRvDT63yZP/CpwHeyth27KJdeqFR Edc6r5dXM4rjPCBlEOIlQk7PPHBz0eu/lFf1o3JULqW7Yq1ZDNHc/7WBWQD2ZLHuKohl v1Cf8CKvIYWVB5F6prc+3lw2L/2uSbOw23NnY53jHFxZKDJff3br4hpAo+OQG4JkBkyb D5nA== X-Gm-Message-State: APjAAAV3xp2UIezZLNuXi4x9uiMTCF6TFr6Lg/S6HXMmel6IoySIqsAK kQx6ihf9KZJKgSbiK0GHBE9qAPdsyl1Y6YR3t0Q= X-Google-Smtp-Source: APXvYqzhnl/od1+4wqmG+HB56zcHmEodlg2M4/tt0l0rrKjOHl/n60b0sUyw2UaMRpO3OuPN2c7IjdKlcyCGNq68Qz4= X-Received: by 2002:a65:5382:: with SMTP id x2mr1469482pgq.420.1572998202872; Tue, 05 Nov 2019 15:56:42 -0800 (PST) Date: Tue, 5 Nov 2019 15:56:04 -0800 In-Reply-To: <20191105235608.107702-1-samitolvanen@google.com> Message-Id: <20191105235608.107702-11-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191105235608.107702-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.rc1.363.gb1bccd3e3d-goog Subject: [PATCH v5 10/14] arm64: preserve x18 when CPU is suspended From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191105_155645_558816_1DC157F0 X-CRM114-Status: GOOD ( 11.42 ) 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 , Jann Horn , Masahiro Yamada , Marc Zyngier , kernel-hardening@lists.openwall.com, Nick Desaulniers , linux-kernel@vger.kernel.org, Miguel Ojeda , clang-built-linux@googlegroups.com, Sami Tolvanen , Laura Abbott , Dave Martin , linux-arm-kernel@lists.infradead.org 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 Don't lose the current task's shadow stack when the CPU is suspended. Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Reviewed-by: Kees Cook --- arch/arm64/include/asm/suspend.h | 2 +- arch/arm64/mm/proc.S | 14 ++++++++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/suspend.h b/arch/arm64/include/asm/suspend.h index 8939c87c4dce..0cde2f473971 100644 --- a/arch/arm64/include/asm/suspend.h +++ b/arch/arm64/include/asm/suspend.h @@ -2,7 +2,7 @@ #ifndef __ASM_SUSPEND_H #define __ASM_SUSPEND_H -#define NR_CTX_REGS 12 +#define NR_CTX_REGS 13 #define NR_CALLEE_SAVED_REGS 12 /* diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index fdabf40a83c8..5c8219c55948 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -49,6 +49,8 @@ * cpu_do_suspend - save CPU registers context * * x0: virtual address of context pointer + * + * This must be kept in sync with struct cpu_suspend_ctx in . */ ENTRY(cpu_do_suspend) mrs x2, tpidr_el0 @@ -73,6 +75,11 @@ alternative_endif stp x8, x9, [x0, #48] stp x10, x11, [x0, #64] stp x12, x13, [x0, #80] + /* + * Save x18 as it may be used as a platform register, e.g. by shadow + * call stack. + */ + str x18, [x0, #96] ret ENDPROC(cpu_do_suspend) @@ -89,6 +96,13 @@ ENTRY(cpu_do_resume) ldp x9, x10, [x0, #48] ldp x11, x12, [x0, #64] ldp x13, x14, [x0, #80] + /* + * Restore x18, as it may be used as a platform register, and clear + * the buffer to minimize the risk of exposure when used for shadow + * call stack. + */ + ldr x18, [x0, #96] + str xzr, [x0, #96] msr tpidr_el0, x2 msr tpidrro_el0, x3 msr contextidr_el1, x4 -- 2.24.0.rc1.363.gb1bccd3e3d-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel