From patchwork Wed May 29 17:36:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1107273 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="ULVwyBSG"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45DdDM5yXrz9s4V for ; Thu, 30 May 2019 03:36:19 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726033AbfE2RgT (ORCPT ); Wed, 29 May 2019 13:36:19 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:49292 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725917AbfE2RgS (ORCPT ); Wed, 29 May 2019 13:36:18 -0400 Received: from pps.filterd (m0109334.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x4THRf4F007082 for ; Wed, 29 May 2019 10:36:18 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=facebook; bh=Li1F9UqFa+Xa1rlr9ak9WLn/iPiFsiufAIWiCeBLLJs=; b=ULVwyBSGlFczzMRAwPZMvCy+Rsp4hWI8ikAXTEgDozWSD/hevmYE2vwhUlbyPhSFn1zC Nf/xtUf5/Fvhsi7FWZ6vcd3y8gd4ioGJ+t9P6T9GszZXaWiF7fZnKWU1IQnu8rlQ+Mb+ lfEuYgj8R29huWUeECsxn+PIc/cP9izJHSE= Received: from mail.thefacebook.com (mailout.thefacebook.com [199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2ssx3ar4j5-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT) for ; Wed, 29 May 2019 10:36:18 -0700 Received: from mx-out.facebook.com (2620:10d:c081:10::13) by mail.thefacebook.com (2620:10d:c081:35::127) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA) id 15.1.1713.5; Wed, 29 May 2019 10:36:18 -0700 Received: by dev101.prn2.facebook.com (Postfix, from userid 137359) id 8D0088617AE; Wed, 29 May 2019 10:36:17 -0700 (PDT) Smtp-Origin-Hostprefix: dev From: Andrii Nakryiko Smtp-Origin-Hostname: dev101.prn2.facebook.com To: , , , , , CC: Andrii Nakryiko Smtp-Origin-Cluster: prn2c23 Subject: [PATCH v2 bpf-next 1/9] libbpf: fix detection of corrupted BPF instructions section Date: Wed, 29 May 2019 10:36:03 -0700 Message-ID: <20190529173611.4012579-2-andriin@fb.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190529173611.4012579-1-andriin@fb.com> References: <20190529173611.4012579-1-andriin@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-05-29_09:, , signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=888 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1905290114 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Ensure that size of a section w/ BPF instruction is exactly a multiple of BPF instruction size. Signed-off-by: Andrii Nakryiko Acked-by: Song Liu --- tools/lib/bpf/libbpf.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index ca4432f5b067..c6c9d632624a 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -349,8 +349,11 @@ static int bpf_program__init(void *data, size_t size, char *section_name, int idx, struct bpf_program *prog) { - if (size < sizeof(struct bpf_insn)) { - pr_warning("corrupted section '%s'\n", section_name); + const size_t bpf_insn_sz = sizeof(struct bpf_insn); + + if (size == 0 || size % bpf_insn_sz) { + pr_warning("corrupted section '%s', size: %zu\n", + section_name, size); return -EINVAL; } @@ -376,9 +379,8 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx, section_name); goto errout; } - prog->insns_cnt = size / sizeof(struct bpf_insn); - memcpy(prog->insns, data, - prog->insns_cnt * sizeof(struct bpf_insn)); + prog->insns_cnt = size / bpf_insn_sz; + memcpy(prog->insns, data, size); prog->idx = idx; prog->instances.fds = NULL; prog->instances.nr = -1;