From patchwork Thu Apr 8 18:28:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192205 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,SPF_PASS, 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 11FC9C433B4 for ; Thu, 8 Apr 2021 18:30:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D487461130 for ; Thu, 8 Apr 2021 18:30:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233081AbhDHSa4 (ORCPT ); Thu, 8 Apr 2021 14:30:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232955AbhDHSaZ (ORCPT ); Thu, 8 Apr 2021 14:30:25 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0CB30C0611A3 for ; Thu, 8 Apr 2021 11:29:17 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id z1so1301731plg.14 for ; Thu, 08 Apr 2021 11:29:17 -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=E//9MgjgyGyGzfpqyqWq2doSFEPDUmVLoRf38lFR7Ug=; b=RkrEMcjEGks9eZDKQu+2cXBVixhfRtfNzurKOb7kj5G0lHbsNG+kVYT00dZ5fCwZZm oGJ3H14LgsxmvSmAONHP3AD4DqcsZiijiViY54PVPWASyhlBWJKul0uk2D6FHPy5MGCI hRwVaWPtPODb24A1fAYvc3Pk8kJw73Wgq0qpJVjB3nsOpeMmHe8UyFYE027vmCmfDH59 TeMeJF97gfJcV1bR86XXNmc9WzLb/xoI5eyDhzlmA3A8LFSbl+CVN1qG+Ng6f1ydMu6m HP+jBZVA3ShA+iChc9OSbbyum7a0Xu8+WCER3+MJXJ4MzHQMgKZMSbyX49ZilNruBraI +ZqQ== 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=E//9MgjgyGyGzfpqyqWq2doSFEPDUmVLoRf38lFR7Ug=; b=f013xZ1ibuC5x5CmcoNE3s2n+vZ1IiYk8vQ5M7FEfI7hN5R1jMKH6lCDiQse5HMNRU H1nF8GYuw9PO2LwMmuzlyL5WgxpVFU79y7mbirKzwgEpudDXS2c06I/1t1WQmPsZCVYM O3mIymxXBmIob4fIWSUmFdF/W0HdKDjcEleXhrbsLcmEGyqpugsF/5uqL2Roh67Yu3co SgWWe+JEo6Z2BcgDwCfpSXPYFZALGpGnBtukZdIDizDfuH9K7MppJjGxpRkmk4uOiXST 208wLzAqCz0ifAysEmlyOhtMiHPD9XVdvuy+FV03yOQ7k9It0hKaaao4vhiUdlDF13Ry 8MPA== X-Gm-Message-State: AOAM531s4FVIdMxAFbwVnK8g1laTILJ5b3LYLJZJiblzBeL9hKlWX7Ii CW3dDY+FWJOw1gXXTzDW6dpE2t/6/Oku+rM9eg4= X-Google-Smtp-Source: ABdhPJxklicbJf72RxeJ+L/uYgGqphrH56F65dx6SJ8/fgnDi6ps2xo+6HGcUO7vtPk7NlHN1dleq0bA9WeA14sn2Uk= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a17:902:7896:b029:e8:fa73:ad22 with SMTP id q22-20020a1709027896b02900e8fa73ad22mr8974621pll.66.1617906556287; Thu, 08 Apr 2021 11:29:16 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:41 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-17-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 16/18] arm64: ftrace: use function_nocfi for ftrace_call 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: linux-kbuild@vger.kernel.org With CONFIG_CFI_CLANG, the compiler replaces function pointers with jump table addresses, which breaks dynamic ftrace as the address of ftrace_call is replaced with the address of ftrace_call.cfi_jt. Use function_nocfi() to get the address of the actual function instead. Suggested-by: Ben Dai Signed-off-by: Sami Tolvanen Acked-by: Mark Rutland Tested-by: Nathan Chancellor --- arch/arm64/kernel/ftrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index 86a5cf9bc19a..b5d3ddaf69d9 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -55,7 +55,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func) unsigned long pc; u32 new; - pc = (unsigned long)&ftrace_call; + pc = (unsigned long)function_nocfi(ftrace_call); new = aarch64_insn_gen_branch_imm(pc, (unsigned long)func, AARCH64_INSN_BRANCH_LINK);