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=-26.3 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, 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 2F338C432BE for ; Mon, 23 Aug 2021 17:14:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19BA4613BD for ; Mon, 23 Aug 2021 17:14:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231814AbhHWRPA (ORCPT ); Mon, 23 Aug 2021 13:15:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231974AbhHWROf (ORCPT ); Mon, 23 Aug 2021 13:14:35 -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 EAE74C06129E for ; Mon, 23 Aug 2021 10:13:52 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id u1-20020a25ab01000000b0059949024617so4126413ybi.17 for ; Mon, 23 Aug 2021 10:13:52 -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=+NWMVXrt3P4ge7VqYOvLEIp/M9aVwCe7Nh6ObW2ZBPc=; b=hFjJ1e+C1MlypS/buKfzRCFkG/9cMbUhkjqvF3HOWHEYkoz3N7NX8cJhjHTYQ/qtyp 2tLkviVOtycQi/lT7Bqo3OcvF5r543o3HOh072GAdPadwN2fE/+AWc/LXwi7Khc8Iprd SbS56lYw5x7Hx6jf25yadN2fNtqR7HBEz8pcM0/wLAUYbWWpj3reFt5V+3jvDDmjFjFl DJ7h/D42e9VHIF14u2DZy+GdSTQ1NQJA0y9trOu84QKzNpJ294yMoilqnBZr1mHcW75V nIygPAcoCxwLFE0WK24aLTNS7BBsZvO+WEqh6pxAazj/ovklE/EFg5oIl7Z+edLMSGWr oWTA== 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=+NWMVXrt3P4ge7VqYOvLEIp/M9aVwCe7Nh6ObW2ZBPc=; b=WHlSCVPp945LXQKs0CQ6AryZ08SNNW+jQoK7pGOt1UYG7gmmmgkn7c3wNfZ1M0mc0R xp+CQ2xAmA1QXjIGqxROsXRmTgPHwmYnHmf0AmHPVOqWjH1X+bDCw05jbrwitFNiekW6 N+r7yEW+Qn+ICEzGmXRlbhgzBvg0Z4akaQnSUMc0VWmhBJS/vZqP8gKn2/+PweD89RU/ +r5OagpsYiXcNm8cSqSq+uQYqMInxtY6oawliJml9FcarrORyqraYF2hCi2YuG284dtf S0P0AOb473TB2mnUOWaUDpFww6DjQspvnLJAsfCX31dQMyx5aF6NbZrtnE613qTQDXtS 27Lw== X-Gm-Message-State: AOAM533UcPGQC3WN5J9SA8rAK+bhp7Ck8RG8kibfhBHtdyTyH/GFRCzk 5a8Umk7V64ymI0vGYO4WiiI1tiVol1Dhyd8zq0A= X-Google-Smtp-Source: ABdhPJxClc9bFSSM1trVCieFK4BS23aESsI41IIN3LRY5ta0ot4fK5RLjCtUzOgKw0Vkr1NLBaaYQnrZtNnFvxI7zRA= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:cc48:aa6a:f4ec:7d19]) (user=samitolvanen job=sendgmr) by 2002:a25:c60f:: with SMTP id k15mr26774743ybf.200.1629738832122; Mon, 23 Aug 2021 10:13:52 -0700 (PDT) Date: Mon, 23 Aug 2021 10:13:17 -0700 In-Reply-To: <20210823171318.2801096-1-samitolvanen@google.com> Message-Id: <20210823171318.2801096-14-samitolvanen@google.com> Mime-Version: 1.0 References: <20210823171318.2801096-1-samitolvanen@google.com> X-Mailer: git-send-email 2.33.0.rc2.250.ged5fa647cd-goog Subject: [PATCH v2 13/14] x86, kprobes: Fix optprobe_template_func type mismatch From: Sami Tolvanen To: x86@kernel.org Cc: Kees Cook , Josh Poimboeuf , Peter Zijlstra , Nathan Chancellor , Nick Desaulniers , Sedat Dilek , linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The optprobe_template_func symbol is defined in inline assembly, but it's not marked global, which conflicts with the C declaration needed for STACK_FRAME_NON_STANDARD and confuses the compiler when CONFIG_CFI_CLANG is enabled. Marking the symbol global would make the compiler happy, but as the compiler also generates a CFI jump table entry for all address-taken functions, the jump table ends up containing a jump to the .rodata section where optprobe_template_func resides, which results in an objtool warning. Use ASM_STACK_FRAME_NON_STANDARD instead to avoid both issues. Signed-off-by: Sami Tolvanen --- arch/x86/kernel/kprobes/opt.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index 71425ebba98a..95375ef5deee 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -103,6 +103,7 @@ static void synthesize_set_arg1(kprobe_opcode_t *addr, unsigned long val) asm ( ".pushsection .rodata\n" "optprobe_template_func:\n" + ASM_STACK_FRAME_NON_STANDARD(optprobe_template_func) ".global optprobe_template_entry\n" "optprobe_template_entry:\n" #ifdef CONFIG_X86_64 @@ -154,9 +155,6 @@ asm ( "optprobe_template_end:\n" ".popsection\n"); -void optprobe_template_func(void); -STACK_FRAME_NON_STANDARD(optprobe_template_func); - #define TMPL_CLAC_IDX \ ((long)optprobe_template_clac - (long)optprobe_template_entry) #define TMPL_MOVE_IDX \ -- 2.33.0.rc2.250.ged5fa647cd-goog