From patchwork Fri Sep 25 00:04:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin KaFai Lau X-Patchwork-Id: 11798503 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C1A1D1580 for ; Fri, 25 Sep 2020 00:04:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D1E423977 for ; Fri, 25 Sep 2020 00:04:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="lD4M+EY7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726873AbgIYAE0 (ORCPT ); Thu, 24 Sep 2020 20:04:26 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:65426 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726858AbgIYAE0 (ORCPT ); Thu, 24 Sep 2020 20:04:26 -0400 Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 08P01D8m014676 for ; Thu, 24 Sep 2020 17:04:24 -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-transfer-encoding : content-type; s=facebook; bh=TWKA/362Z4Sfry1/5te0HavQDohYlFdNSVMuX+6GcTA=; b=lD4M+EY705/Anjl4ysnUpwfpHn1suXlQaVAH//ihCrhPr1viZ66+pB6pxuV0UHPToplP spV33aTDfx3CDP6ha0N5Mk0F4I1ELZ8XR+5NiZV2zG3wYb6B2Sn55Kmj3oF8bbXLkhXQ FObmSOFeDY6uLtSwzD8gN1vAf5X7PDgZ01c= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 33qsp54rc7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 24 Sep 2020 17:04:24 -0700 Received: from intmgw001.08.frc2.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:11d::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Thu, 24 Sep 2020 17:04:23 -0700 Received: by devbig005.ftw2.facebook.com (Postfix, from userid 6611) id 876642946606; Thu, 24 Sep 2020 17:04:21 -0700 (PDT) From: Martin KaFai Lau To: CC: Alexei Starovoitov , Daniel Borkmann , , Lorenz Bauer , Subject: [PATCH v4 bpf-next 07/13] bpf: selftest: Add ref_tracking verifier test for bpf_skc casting Date: Thu, 24 Sep 2020 17:04:21 -0700 Message-ID: <20200925000421.3857616-1-kafai@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200925000337.3853598-1-kafai@fb.com> References: <20200925000337.3853598-1-kafai@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-09-24_18:2020-09-24,2020-09-24 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxlogscore=830 spamscore=0 bulkscore=0 impostorscore=0 malwarescore=0 phishscore=0 clxscore=1015 priorityscore=1501 mlxscore=0 suspectscore=13 adultscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009240174 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org The patch tests for: 1. bpf_sk_release() can be called on a tcp_sock btf_id ptr. 2. Ensure the tcp_sock btf_id pointer cannot be used after bpf_sk_release(). Signed-off-by: Martin KaFai Lau Acked-by: Lorenz Bauer --- .../selftests/bpf/verifier/ref_tracking.c | 47 +++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/tools/testing/selftests/bpf/verifier/ref_tracking.c b/tools/testing/selftests/bpf/verifier/ref_tracking.c index 056e0273bf12..006b5bd99c08 100644 --- a/tools/testing/selftests/bpf/verifier/ref_tracking.c +++ b/tools/testing/selftests/bpf/verifier/ref_tracking.c @@ -854,3 +854,50 @@ .errstr = "Unreleased reference", .result = REJECT, }, +{ + "reference tracking: bpf_sk_release(btf_tcp_sock)", + .insns = { + BPF_SK_LOOKUP(sk_lookup_tcp), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), + BPF_EXIT_INSN(), + BPF_MOV64_REG(BPF_REG_6, BPF_REG_0), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_EMIT_CALL(BPF_FUNC_skc_to_tcp_sock), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 3), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_6), + BPF_EMIT_CALL(BPF_FUNC_sk_release), + BPF_EXIT_INSN(), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_EMIT_CALL(BPF_FUNC_sk_release), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .result = ACCEPT, + .result_unpriv = REJECT, + .errstr_unpriv = "unknown func", +}, +{ + "reference tracking: use ptr from bpf_skc_to_tcp_sock() after release", + .insns = { + BPF_SK_LOOKUP(sk_lookup_tcp), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), + BPF_EXIT_INSN(), + BPF_MOV64_REG(BPF_REG_6, BPF_REG_0), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_EMIT_CALL(BPF_FUNC_skc_to_tcp_sock), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 3), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_6), + BPF_EMIT_CALL(BPF_FUNC_sk_release), + BPF_EXIT_INSN(), + BPF_MOV64_REG(BPF_REG_7, BPF_REG_0), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_6), + BPF_EMIT_CALL(BPF_FUNC_sk_release), + BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_7, 0), + BPF_EXIT_INSN(), + }, + .prog_type = BPF_PROG_TYPE_SCHED_CLS, + .result = REJECT, + .errstr = "invalid mem access", + .result_unpriv = REJECT, + .errstr_unpriv = "unknown func", +},