From patchwork Thu Apr 8 18:28:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192165 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=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 BCE3BC43611 for ; Thu, 8 Apr 2021 18:30:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 830EB61108 for ; Thu, 8 Apr 2021 18:30:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233073AbhDHSa4 (ORCPT ); Thu, 8 Apr 2021 14:30:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48734 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232910AbhDHSaY (ORCPT ); Thu, 8 Apr 2021 14:30:24 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0966FC061221 for ; Thu, 8 Apr 2021 11:29:15 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id x7so2881874ybs.10 for ; Thu, 08 Apr 2021 11:29:15 -0700 (PDT) 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=vPR3ETOAeMW95pC8NAj24CpgqHEbd4yevcfxmcZ1/jA=; b=X+q7fW6iH/r7Id1WxE7msv5xTVPwRxH/FYjuCYgT4Moo6FV8A561Dq9/qDbuWOYoQy baU/9OXT+9MhCyfixUI7yCjK+ouetQotIr0A3byFRLhqfbDZwfq0jQeOgYcGZAVSXsJQ rPLDUKrO/h0fwc+Y23KNdHLXq7kpJvM/AJu180+tpnHtEUdNyCTbPYv+2c0evgyiiN/9 DYuW8WvqrmguI16PEhoEl8kXGUOzNFzvOQMzRbvdY9vjeLBlXU2tFWIIpicfR7DHAKtW l85fWs5YCAXplevIrasowB3fIqDAD3r9GAVM2gPSRCq5P1neWWHzeeVd7klLc/lM1qYM sXYw== 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=vPR3ETOAeMW95pC8NAj24CpgqHEbd4yevcfxmcZ1/jA=; b=Uc0K9PDhNwEHYHgegSBXL0PkXNIhrtGR3BYWKoPuhzLTbvia7KmnfzTojaf/5dSeht 1YJfD94qTKyDgQjNSHF+B9dIYIrsKNjngRAFKGP8kp+r4FIG2/S9VP0Z567BZN1SoynV 8ZX+8QidYpKjyBui4G+a788G9bl16t0b+F93niXbLK+e2iFgX83P8NEbR8Wo4u+HWU7S nSTwOzoIQ0YSrlzl+5j2l0pb01a86PL6n9WM/W/dhqrp5r0yUy37N+MhvKu6DXNK3XCl U9+YwL/eV8niHHcmgy1Ou7Fi6iC9hiZ4v6oOHvPkzP9ReiRmStHL4aJwFt5HD3AD/Ovn hNGQ== X-Gm-Message-State: AOAM530gNt2nWpCLQ2Tx29LSQ48PdBhWK1PoP+k28i3kDUtTTwlHvus1 WFyVoh1VOw07uvTQUNFlalkgg7doKWnmHTxC568= X-Google-Smtp-Source: ABdhPJz/su5s3FJ4/ClB/3zgcLUsgjK5PoygW68wgkC4KNGGvsbw78PuGtzLYwUALhEPddWcHuMOQsCUu2Cq7CZyhzI= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:b90c:: with SMTP id x12mr13955922ybj.12.1617906554210; Thu, 08 Apr 2021 11:29:14 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:40 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-16-samitolvanen@google.com> Mime-Version: 1.0 References: <20210408182843.1754385-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog Subject: [PATCH v6 15/18] arm64: add __nocfi to __apply_alternatives From: Sami Tolvanen To: Kees Cook Cc: Nathan Chancellor , Nick Desaulniers , Masahiro Yamada , Will Deacon , Jessica Yu , Arnd Bergmann , Tejun Heo , "Paul E. McKenney" , Christoph Hellwig , Peter Zijlstra , Sedat Dilek , Mark Rutland , Catalin Marinas , bpf@vger.kernel.org, linux-hardening@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org __apply_alternatives makes indirect calls to functions whose address is taken in assembly code using the alternative_cb macro. With non-canonical CFI, the compiler won't replace these function references with the jump table addresses, which trips CFI. Disable CFI checking in the function to work around the issue. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- arch/arm64/kernel/alternative.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index 1184c44ea2c7..abc84636af07 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -133,8 +133,8 @@ static void clean_dcache_range_nopatch(u64 start, u64 end) } while (cur += d_size, cur < end); } -static void __apply_alternatives(void *alt_region, bool is_module, - unsigned long *feature_mask) +static void __nocfi __apply_alternatives(void *alt_region, bool is_module, + unsigned long *feature_mask) { struct alt_instr *alt; struct alt_region *region = alt_region;