From patchwork Tue Nov 5 20:58:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 11228599 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4F3C91390 for ; Tue, 5 Nov 2019 21:07:41 +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 2EF4721882 for ; Tue, 5 Nov 2019 21:07:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="tlKsDspE"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="mls0iUz0" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2EF4721882 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.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:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=UeGlO8GemSMKRjA6armQDOZz1F9KVPdcKmo8er05I9U=; b=tlKsDspEqN3pja53LPz8LLbC1Q 6KiTyNoDmNWu6zO4OhIieppaI5yCUW9a7YI/CIRI6hg3etYlmCdgfaXmu4rYAX4f/DLJQlfNPp+lX iqtiGQrzEeN1fYjXKbv7XTyzU0VYbgK2aiBCGNT9HsziAMLM80IAHs/vOEDrGFBQiPrmQ+LkzAYqq R06zOy+OwR3+JQixBpizwDCjKzTgwauabS67dfzCk+N+3DG2nm+p+c7wUAqD9dWnZHCDu8jNvuH6p kLNHEvWX3mkcoEfZc23lTcLtGn3jn/zt2QBsgRjsqFgFU9tzSeZRPJWz9YM7oxZzofIxFqVn3Bkh5 k/yRlfSw==; 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 1iS638-0007EC-HC; Tue, 05 Nov 2019 21:07:38 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iS5wB-0007fU-ST for linux-arm-kernel@lists.infradead.org; Tue, 05 Nov 2019 21:00:29 +0000 Received: from e123331-lin.home (lfbn-mar-1-643-104.w90-118.abo.wanadoo.fr [90.118.215.104]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C32EB21D6C; Tue, 5 Nov 2019 21:00:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572987627; bh=HZUHLYdRGJUrgy226Rwadpm2bQuFrlaAit8XjlBcYu0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mls0iUz0r7fkkT/MStZ3Y20s1m64DxAeRn1c8TpZmUpBeZfsG2cXe6/oBrUbipAph Rsm7Qa/R8cDw8+8XoTdDjc1RAAC3SkAzvpQhEPCiiq9pV5y4qavA4bvEO6wnTz+GvM oNf7M8De3YnPAzpFS0w70rfy2s/+2jqzu8ElpeL8= From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Subject: [PATCH for-stable-v4.4 31/53] ARM: spectre-v1: add array_index_mask_nospec() implementation Date: Tue, 5 Nov 2019 21:58:24 +0100 Message-Id: <20191105205846.1394-32-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191105205846.1394-1-ardb@kernel.org> References: <20191105205846.1394-1-ardb@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191105_130027_955324_F739DE70 X-CRM114-Status: GOOD ( 10.42 ) X-Spam-Score: -5.2 (-----) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (-5.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender 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 , Florian Fainelli , Greg Kroah-Hartman , Tony Lindgren , Catalin Marinas , Russell King , "David A . Long" , Marc Zyngier , Will Deacon , Ard Biesheuvel MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org From: Russell King Commit 1d4238c56f9816ce0f9c8dbe42d7f2ad81cb6613 upstream. Add an implementation of the array_index_mask_nospec() function for mitigating Spectre variant 1 throughout the kernel. Signed-off-by: Russell King Acked-by: Mark Rutland Boot-tested-by: Tony Lindgren Reviewed-by: Tony Lindgren Signed-off-by: David A. Long Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ard Biesheuvel --- arch/arm/include/asm/barrier.h | 21 ++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h index edd9e633a84b..8514b70704de 100644 --- a/arch/arm/include/asm/barrier.h +++ b/arch/arm/include/asm/barrier.h @@ -108,5 +108,26 @@ do { \ #define smp_mb__before_atomic() smp_mb() #define smp_mb__after_atomic() smp_mb() +#ifdef CONFIG_CPU_SPECTRE +static inline unsigned long array_index_mask_nospec(unsigned long idx, + unsigned long sz) +{ + unsigned long mask; + + asm volatile( + "cmp %1, %2\n" + " sbc %0, %1, %1\n" + CSDB + : "=r" (mask) + : "r" (idx), "Ir" (sz) + : "cc"); + + return mask; +} +#define array_index_mask_nospec array_index_mask_nospec +#endif + +#include + #endif /* !__ASSEMBLY__ */ #endif /* __ASM_BARRIER_H */