From patchwork Fri Mar 12 00:49:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 12133459 X-Patchwork-Delegate: bpf@iogearbox.net 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 7DB05C28EBD for ; Fri, 12 Mar 2021 00:50:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6576C64F82 for ; Fri, 12 Mar 2021 00:50:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231659AbhCLAtu (ORCPT ); Thu, 11 Mar 2021 19:49:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52078 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231398AbhCLAtg (ORCPT ); Thu, 11 Mar 2021 19:49:36 -0500 Received: from mail-qv1-xf4a.google.com (mail-qv1-xf4a.google.com [IPv6:2607:f8b0:4864:20::f4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39A07C061760 for ; Thu, 11 Mar 2021 16:49:36 -0800 (PST) Received: by mail-qv1-xf4a.google.com with SMTP id iy2so16416168qvb.22 for ; Thu, 11 Mar 2021 16:49:36 -0800 (PST) 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=YI9ktuFU/X+08fuezAEyeT/4YV7bN+r3OwkJvmEu6tA=; b=G4eTVdB9vYaxNQeExEZkD7EJkKoXsPP1Mh7LeCv9UXYddhsCLBhNTAoGc8Y7X0A8l2 Eyxb/mtwuF7AwGkZiQuyYBMJmmM23sBMA3tcJOEtvTf0tH2JYPyDcNgFnaeQwXmmMDjM kT8iaz+E1+HtZZiLkju9VH1kkQDUYpLvvXxaYE5rDiD/TLuSHoi6XKfJWOSdgFSk556n Pr7pM6PcY4QwA2g5BI6EXwuZnKgI4oK61gOGJ8t362oU8kuePT3xDFXSPJlqe/NN7rJX muliusPDNXzM8lZ2u3UaTA3NwKZNAvbL6g0DQbhEZaD1olkczwuySFpVS6Q4wmahv7BJ gM0A== 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=YI9ktuFU/X+08fuezAEyeT/4YV7bN+r3OwkJvmEu6tA=; b=BHhOvFYzkzwQCDDQV5MH07lUKEjHeAvhXs8lcXDaY/N01I6OpwwiORdAWL8gu7m3a1 RcocjP79cNibPH1bnZz/f/HawUXFeNOllLA5aHU3m4MHiuEuVVEYVGGuE4nn2FCNTGQS V1jpggKPRtN0rhIRNkz1yRDanWuJhEkxMnzpzrh2tbbaFDWZudpS0NVdKYzgSY7WMqV3 MnmtdqVCi0jVUsnUgOGoQrlAJy8IdOV7u8bx7mAbU7s/qlzxwqbT2xcz3n3l+2iLuUlg +VpegWzq7Ak5krP+5D8ZJA3q0wQB+mseAR+Rz4iQPwqYAjlLMKyLsJoSsZfNKbnld5rE tksA== X-Gm-Message-State: AOAM5315C24rLGRrqakrlXvI8/PPPVNT7poTycTYoArgXgPEf8NR2fXc BZRSwyZdALAiKULmvNVIUjcGUqxQVwClVy6mAKs= X-Google-Smtp-Source: ABdhPJzI9rK5QlDj5oqSuS2czS9rEOHva7EAYyuXoiJYgIvPrvHH3npr11wyk+ga7aI1sfu0nIaCQs6FMxQcyq1QB0Y= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:c86b:8269:af92:55a]) (user=samitolvanen job=sendgmr) by 2002:ad4:4b6c:: with SMTP id m12mr9997739qvx.21.1615510175432; Thu, 11 Mar 2021 16:49:35 -0800 (PST) Date: Thu, 11 Mar 2021 16:49:10 -0800 In-Reply-To: <20210312004919.669614-1-samitolvanen@google.com> Message-Id: <20210312004919.669614-9-samitolvanen@google.com> Mime-Version: 1.0 References: <20210312004919.669614-1-samitolvanen@google.com> X-Mailer: git-send-email 2.31.0.rc2.261.g7f71774620-goog Subject: [PATCH 08/17] 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 , 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, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net 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 --- 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 cccaef1088ea..9acdca574527 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -635,7 +635,7 @@ 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 *, @@ -663,7 +663,7 @@ 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 *, \