From patchwork Thu Apr 8 18:28:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12192189 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 768DCC433B4 for ; Thu, 8 Apr 2021 18:29:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59CFE610FC for ; Thu, 8 Apr 2021 18:29:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232891AbhDHS3y (ORCPT ); Thu, 8 Apr 2021 14:29:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232956AbhDHS3a (ORCPT ); Thu, 8 Apr 2021 14:29:30 -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 C1F2FC061794 for ; Thu, 8 Apr 2021 11:29:01 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 131so2862051ybp.16 for ; Thu, 08 Apr 2021 11:29:01 -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=T2ovzaB0NMgTSr/OQHoRsOuIMdugM8hNdn5wpYAlfF8=; b=b/XnAFSzIGeFZL5t4c3a08ji5ExjHKdf/SwND+STd8nJjKG2hFi8IK6+LIkx2BL1C9 wA58dA9Twv0RudfR+z0WKHeJHzBjE5MCPeNpBMSpRhTqgwMv1lMdb5OMvQvJs03AJdqF cvNhS4rRrIm5NEuMJcbOn0Qic4skZtQ7ODdDOjE+31zXh7wKiynNzNVauckEuvoTxUxC kDIa3FfiN8wZ72m0SiVMTOm77/X5XsJn517NuQnl/oz5AyexntdTHwnjiUme+uS7gPSa RYYiKdwwNKXeM2PUjRJWR//28taSyDm0VOQQzPOC2K3Pq3M24yOOt7lwowsUBlWOxQbw tw4w== 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=T2ovzaB0NMgTSr/OQHoRsOuIMdugM8hNdn5wpYAlfF8=; b=gOIJyqSt0KPLPGtOP6hwRLP1aH15S5l4q+YzXv499isqFGy8itVFVARozbUoZ0zeo4 K22WfkCnNymIpiyKE7sLdTHbFUB+lFsacxkoRulwQtBOdsDK3QOBH8lz9aDx4wODSEZj uYxIv48Bqz+eqSCKQZQbP0mSXBFZ0ydH2LG8U+5vtAi8rzQJN4Aw8bZxGamdTPi0iMpL s5JiH7y+ZmeBGr3FG/r+4AbRRDzsTX9EcWRrejxmJ0YpFUdeyMkh4v6yrI3s6lntm90h 1JkoKlzMHad82HV9ttriwYK+k270CXK7ie2acFqahXADeikVXcheC8QH++ZZUrAbhQhO /u2Q== X-Gm-Message-State: AOAM530qul0ms1sHuemnt8rKB/3arMhsbgAHYyvb5lqY73ohdcLY1zVB 7m6gUOpPWhQWyd13mOXWN3u62fel8z0pjsS/430= X-Google-Smtp-Source: ABdhPJy28p/s1E3yXdiEmOPhfW5oMkIPebIbR+7sk7/VA4kOnWJlonwcxFpLfp3KgtW+U+9qgib7kFL/mIu5lYyr5IA= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:3560:8505:40a2:e021]) (user=samitolvanen job=sendgmr) by 2002:a25:fc05:: with SMTP id v5mr2410558ybd.192.1617906540963; Thu, 08 Apr 2021 11:29:00 -0700 (PDT) Date: Thu, 8 Apr 2021 11:28:33 -0700 In-Reply-To: <20210408182843.1754385-1-samitolvanen@google.com> Message-Id: <20210408182843.1754385-9-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 08/18] bpf: disable CFI in dispatcher functions 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 BPF dispatcher functions are patched at runtime to perform direct instead of indirect calls. Disable CFI for the dispatcher functions to avoid conflicts. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nathan Chancellor --- include/linux/bpf.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 3625f019767d..2f46f98479e1 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -650,7 +650,7 @@ struct bpf_dispatcher { struct bpf_ksym ksym; }; -static __always_inline unsigned int bpf_dispatcher_nop_func( +static __always_inline __nocfi unsigned int bpf_dispatcher_nop_func( const void *ctx, const struct bpf_insn *insnsi, unsigned int (*bpf_func)(const void *, @@ -678,7 +678,7 @@ void bpf_trampoline_put(struct bpf_trampoline *tr); } #define DEFINE_BPF_DISPATCHER(name) \ - noinline unsigned int bpf_dispatcher_##name##_func( \ + noinline __nocfi unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ unsigned int (*bpf_func)(const void *, \