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=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 9FE0CC388F2 for ; Tue, 3 Nov 2020 00:51:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4250022258 for ; Tue, 3 Nov 2020 00:51:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="FYjgwMd2"; dkim=pass (1024-bit key) header.d=fb.onmicrosoft.com header.i=@fb.onmicrosoft.com header.b="SzezOZvr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726460AbgKCAvy (ORCPT ); Mon, 2 Nov 2020 19:51:54 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:26474 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725855AbgKCAvy (ORCPT ); Mon, 2 Nov 2020 19:51:54 -0500 Received: from pps.filterd (m0148461.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0A30iBq2028292; Mon, 2 Nov 2020 16:51:41 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-id : content-transfer-encoding : mime-version; s=facebook; bh=31EkLIJGs/nGyWKZptMR1D0EuOQwLGKwLqE3pXm8Ymw=; b=FYjgwMd2VU49lnx2gZhjm5g/fwxq8yRp9BmMFsUbLufL4s1VONXWo6RfucsjWSdApCiX UbVuEoqu0SGH7Z9IoKnYQ2ObbfbfJF04hw/fTBfmxTOEZnpogyOnVfR/uWSYUsBSjvL9 w5QkCN2Rryyq/bxZNGy7oS1jKn7Xx7BrEFI= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 34hr6p0a9v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Mon, 02 Nov 2020 16:51:41 -0800 Received: from NAM10-MW2-obe.outbound.protection.outlook.com (100.104.31.183) by o365-in.thefacebook.com (100.104.35.175) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Mon, 2 Nov 2020 16:51:39 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=aOFYox/7CeRpKmU3bui7XSEfG8KJeUx35itikkZaGc3kG8rZ+fy9xRfojdHcchSV6PKnsiRcdLtvfIIXN+sJeoc92eXuvJRUBFqLpvDRkXUquLvpFc6AeMmoJLfAnyw9Kny1YmWCJhlWZVuuPFXn2ssYHhukj85nPvqhVBZvXUEaOgmsfzJGcpPy970wifT9C2Z+LqeK8OMfpBFVQMj7TmawSvGBMeoUju/Odv2YBVZ5ruJEgYujlQKVarIWRC8uBnof70n/0IDmmLN7HHJjCKpsBU0rTIIHP86+KXYnqrTHZJ01N4OYwHofK4t+uT6/DJ0aREfoOwQ+oS1cBEFMZw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=31EkLIJGs/nGyWKZptMR1D0EuOQwLGKwLqE3pXm8Ymw=; b=LmKDwOvHgFtQJxvfAoamw2udcG5FGZCruUxAvrXbbZ83m7MxbYSEbLf/QSmUAy1LfGczbThR02BZsFlap54AyqDA2/HdM7HMlYGeeq6ZIKIJpBguPs/lwxUGJWxsrXaVqsCwyr3Mi7yuwoVj734m0zLjnAX5KKtXaqvxSj/fy/AlrmMKb/t6VL+RcVcqb0Eqn0PF0WN2JExR2h0FAqJ1/vJdftYH9y9Ef2p1eD6MdeywPb8jos5+mOv2r2SVCLPq9u6WE0tl4TO0P7vNXOJASWsV0RJSf5U13RF0PYXMcTez8kc81djEGC9yYojTqQKLl9IMTxSaNHgdsPS45by5iA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=fb.com; dmarc=pass action=none header.from=fb.com; dkim=pass header.d=fb.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.onmicrosoft.com; s=selector2-fb-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=31EkLIJGs/nGyWKZptMR1D0EuOQwLGKwLqE3pXm8Ymw=; b=SzezOZvr5oFPPCMsZa9OLtUduVUmmc4lwv8RQN5/8t4vbqsxRgX/w/bUiEfCiLsMMQtD1iEZGGBpLJtHTlQo0uPN+fyHT4e9xeUR1vnnlrdtp0aYo2LNUNBvGqUCzVbBuVUB2VWck6tj60z9iRnhJuku4hs/gyohASECwEeQnqw= Received: from BYAPR15MB2999.namprd15.prod.outlook.com (2603:10b6:a03:fa::12) by BYAPR15MB2567.namprd15.prod.outlook.com (2603:10b6:a03:151::13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3499.18; Tue, 3 Nov 2020 00:51:36 +0000 Received: from BYAPR15MB2999.namprd15.prod.outlook.com ([fe80::7d77:205b:bbc4:4c70]) by BYAPR15MB2999.namprd15.prod.outlook.com ([fe80::7d77:205b:bbc4:4c70%6]) with mapi id 15.20.3499.030; Tue, 3 Nov 2020 00:51:36 +0000 From: Song Liu To: Andrii Nakryiko CC: bpf , Networking , "Alexei Starovoitov" , Daniel Borkmann , Kernel Team Subject: Re: [PATCH bpf-next 07/11] libbpf: fix BTF data layout checks and allow empty BTF Thread-Topic: [PATCH bpf-next 07/11] libbpf: fix BTF data layout checks and allow empty BTF Thread-Index: AQHWrY7NHg7l4OivSECIeWatLilZlqm1m9eA Date: Tue, 3 Nov 2020 00:51:36 +0000 Message-ID: References: <20201029005902.1706310-1-andrii@kernel.org> <20201029005902.1706310-8-andrii@kernel.org> In-Reply-To: <20201029005902.1706310-8-andrii@kernel.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-mailer: Apple Mail (2.3608.120.23.2.4) authentication-results: kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=fb.com; x-originating-ip: [2620:10d:c090:400::5:c2a2] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 914af852-190f-4ff9-b07e-08d87f929e1f x-ms-traffictypediagnostic: BYAPR15MB2567: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-fb-source: Internal x-ms-oob-tlc-oobclassifiers: OLM:1824; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: EeuYwEc+Db1hGTD04JJdmzKsFlkvRSv36rLbSG5jAyyMxasIpsEHdVid3KAevP5m0AXx34BpQdeJTB6bxnUJXUe1Au9RTXZ3/XtDEj8a/msEz3zeVcjYh0kW3V5+NA4bVzx+ImgpD6KfB7MmgTxKl5qhXRfQcV7ekq1FesMJwMCGT+DDZrbfoFcNUQuHum3klL1Jn54kUplNaLMdA5mcdCUYuUmxwy1aFI0rH5YCk2VB1VRu78Cy8njL5cgkVZDb6xCb+iBdSlf64hA8Dof0YAvxsHwRrrEy8XChz30OVCspDDkqVMsttHdFQt9N71RZSXwbqZ5WPBlaGznj34ZH5A== x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR15MB2999.namprd15.prod.outlook.com;PTR:;CAT:NONE;SFS:(346002)(376002)(396003)(39860400002)(366004)(136003)(54906003)(316002)(8676002)(4326008)(36756003)(6916009)(186003)(86362001)(2906002)(6512007)(6486002)(478600001)(6506007)(8936002)(33656002)(2616005)(66946007)(53546011)(76116006)(91956017)(71200400001)(5660300002)(83380400001)(64756008)(66446008)(66476007)(66556008);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata: 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 Content-Type: text/plain; charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BYAPR15MB2999.namprd15.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 914af852-190f-4ff9-b07e-08d87f929e1f X-MS-Exchange-CrossTenant-originalarrivaltime: 03 Nov 2020 00:51:36.6415 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: H7Pg8uw6orCNYeMYQVKmBMMWUXarU0MtDH0HkbGIurTf0hhREJwCH7jGXnrd0Ev7yDc0Dyu27unS+HD3qinHzA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB2567 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312,18.0.737 definitions=2020-11-02_16:2020-11-02,2020-11-02 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 malwarescore=0 phishscore=0 clxscore=1015 lowpriorityscore=0 adultscore=0 mlxscore=0 bulkscore=0 suspectscore=0 mlxlogscore=999 spamscore=0 priorityscore=1501 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2011030002 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org > On Oct 28, 2020, at 5:58 PM, Andrii Nakryiko wrote: >=20 > Make data section layout checks stricter, disallowing overlap of types an= d > strings data. >=20 > Additionally, allow BTFs with no type data. There is nothing inherently w= rong > with having BTF with no types (put potentially with some strings). This c= ould > be a situation with kernel module BTFs, if module doesn't introduce any n= ew > type information. >=20 > Also fix invalid offset alignment check for btf->hdr->type_off. >=20 > Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf") > Signed-off-by: Andrii Nakryiko > --- > tools/lib/bpf/btf.c | 16 ++++++---------- > 1 file changed, 6 insertions(+), 10 deletions(-) >=20 > diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c > index 20c64a8441a8..9b0ef71a03d0 100644 > --- a/tools/lib/bpf/btf.c > +++ b/tools/lib/bpf/btf.c > @@ -245,22 +245,18 @@ static int btf_parse_hdr(struct btf *btf) > return -EINVAL; > } >=20 > - if (meta_left < hdr->type_off) { > - pr_debug("Invalid BTF type section offset:%u\n", hdr->type_off); > + if (meta_left < hdr->str_off + hdr->str_len) { > + pr_debug("Invalid BTF total size:%u\n", btf->raw_size); > return -EINVAL; > } Can we make this one as=20 if (meta_left !=3D hdr->str_off + hdr->str_len) { >=20 > - if (meta_left < hdr->str_off) { > - pr_debug("Invalid BTF string section offset:%u\n", hdr->str_off); > + if (hdr->type_off + hdr->type_len > hdr->str_off) { > + pr_debug("Invalid BTF data sections layout: type data at %u + %u, stri= ngs data at %u + %u\n", > + hdr->type_off, hdr->type_len, hdr->str_off, hdr->str_len); > return -EINVAL; > } And this one=20 if (hdr->type_off + hdr->type_len !=3D hdr->str_off) { ? [...]=