From patchwork Wed Sep 27 22:58:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 13401785 X-Patchwork-Delegate: paul@paul-moore.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 78FE6E80ABC for ; Wed, 27 Sep 2023 23:02:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230054AbjI0XCS convert rfc822-to-8bit (ORCPT ); Wed, 27 Sep 2023 19:02:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229675AbjI0XB5 (ORCPT ); Wed, 27 Sep 2023 19:01:57 -0400 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 212E4F5 for ; Wed, 27 Sep 2023 16:01:56 -0700 (PDT) Received: from pps.filterd (m0148460.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 38RLUA9u032745 for ; Wed, 27 Sep 2023 16:01:55 -0700 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3tcvbsrqjm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 27 Sep 2023 16:01:55 -0700 Received: from twshared44805.48.prn1.facebook.com (2620:10d:c0a8:1c::1b) by mail.thefacebook.com (2620:10d:c0a8:82::b) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Wed, 27 Sep 2023 16:01:45 -0700 Received: by devbig019.vll3.facebook.com (Postfix, from userid 137359) id 9541138C9A66A; Wed, 27 Sep 2023 15:58:42 -0700 (PDT) From: Andrii Nakryiko To: , CC: , , , , , , Subject: [PATCH v6 bpf-next 05/13] bpf: add BPF token support to BPF_BTF_LOAD command Date: Wed, 27 Sep 2023 15:58:01 -0700 Message-ID: <20230927225809.2049655-6-andrii@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230927225809.2049655-1-andrii@kernel.org> References: <20230927225809.2049655-1-andrii@kernel.org> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: -TH6SqPCILnVPQjJtaJoWVh3sSEFAWwe X-Proofpoint-ORIG-GUID: -TH6SqPCILnVPQjJtaJoWVh3sSEFAWwe X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-09-27_15,2023-09-27_01,2023-05-22_02 Precedence: bulk List-ID: Accept BPF token FD in BPF_BTF_LOAD command to allow BTF data loading through delegated BPF token. BTF loading is a pretty straightforward operation, so as long as BPF token is created with allow_cmds granting BPF_BTF_LOAD command, kernel proceeds to parsing BTF data and creating BTF object. Signed-off-by: Andrii Nakryiko --- include/uapi/linux/bpf.h | 1 + kernel/bpf/syscall.c | 20 ++++++++++++++++++-- tools/include/uapi/linux/bpf.h | 1 + 3 files changed, 20 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index dcc429eb3c89..6c4651176046 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1606,6 +1606,7 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 btf_log_true_size; + __u32 btf_token_fd; }; struct { diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 7a1a8495d490..5c5c2b6648b2 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -4712,15 +4712,31 @@ static int bpf_obj_get_info_by_fd(const union bpf_attr *attr, return err; } -#define BPF_BTF_LOAD_LAST_FIELD btf_log_true_size +#define BPF_BTF_LOAD_LAST_FIELD btf_token_fd static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size) { + struct bpf_token *token = NULL; + if (CHECK_ATTR(BPF_BTF_LOAD)) return -EINVAL; - if (!bpf_capable()) + if (attr->btf_token_fd) { + token = bpf_token_get_from_fd(attr->btf_token_fd); + if (IS_ERR(token)) + return PTR_ERR(token); + if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) { + bpf_token_put(token); + token = NULL; + } + } + + if (!bpf_token_capable(token, CAP_BPF)) { + bpf_token_put(token); return -EPERM; + } + + bpf_token_put(token); return btf_new_fd(attr, uattr, uattr_size); } diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index dcc429eb3c89..6c4651176046 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1606,6 +1606,7 @@ union bpf_attr { * truncated), or smaller (if log buffer wasn't filled completely). */ __u32 btf_log_true_size; + __u32 btf_token_fd; }; struct {