From patchwork Wed May 8 22:50:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Lemon X-Patchwork-Id: 1097274 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@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=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=gmail.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44zsBT4Mc2z9s5c for ; Thu, 9 May 2019 08:50:25 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727400AbfEHWuX (ORCPT ); Wed, 8 May 2019 18:50:23 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:55578 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725910AbfEHWuV (ORCPT ); Wed, 8 May 2019 18:50:21 -0400 Received: from pps.filterd (m0001255.ppops.net [127.0.0.1]) by mx0b-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x48MgYm7015269 for ; Wed, 8 May 2019 15:50:20 -0700 Received: from mail.thefacebook.com (mailout.thefacebook.com [199.201.64.23]) by mx0b-00082601.pphosted.com with ESMTP id 2sc50u8q7x-6 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT) for ; Wed, 08 May 2019 15:50:20 -0700 Received: from mx-out.facebook.com (2620:10d:c081:10::13) by mail.thefacebook.com (2620:10d:c081:35::128) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA) id 15.1.1713.5; Wed, 8 May 2019 15:50:17 -0700 Received: by devvm34215.prn1.facebook.com (Postfix, from userid 172786) id 989AA220D8337; Wed, 8 May 2019 15:50:16 -0700 (PDT) Smtp-Origin-Hostprefix: devvm From: Jonathan Lemon Smtp-Origin-Hostname: devvm34215.prn1.facebook.com To: , , , CC: Smtp-Origin-Cluster: prn1c35 Subject: [PATCH bpf-next 1/2] bpf: Allow bpf_map_lookup_elem() on an xskmap Date: Wed, 8 May 2019 15:50:15 -0700 Message-ID: <20190508225016.2375828-1-jonathan.lemon@gmail.com> X-Mailer: git-send-email 2.17.1 X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-05-08_12:, , signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Currently, the AF_XDP code uses a separate map in order to determine if an xsk is bound to a queue. Instead of doing this, have bpf_map_lookup_elem() return a boolean indicating whether there is a valid entry at the map index. Signed-off-by: Jonathan Lemon --- kernel/bpf/verifier.c | 6 +++++- kernel/bpf/xskmap.c | 2 +- .../selftests/bpf/verifier/prevent_map_lookup.c | 15 --------------- 3 files changed, 6 insertions(+), 17 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 7b05e8938d5c..a8b8ff9ecd90 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2761,10 +2761,14 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, * appear. */ case BPF_MAP_TYPE_CPUMAP: - case BPF_MAP_TYPE_XSKMAP: if (func_id != BPF_FUNC_redirect_map) goto error; break; + case BPF_MAP_TYPE_XSKMAP: + if (func_id != BPF_FUNC_redirect_map && + func_id != BPF_FUNC_map_lookup_elem) + goto error; + break; case BPF_MAP_TYPE_ARRAY_OF_MAPS: case BPF_MAP_TYPE_HASH_OF_MAPS: if (func_id != BPF_FUNC_map_lookup_elem) diff --git a/kernel/bpf/xskmap.c b/kernel/bpf/xskmap.c index 686d244e798d..f6e49237979c 100644 --- a/kernel/bpf/xskmap.c +++ b/kernel/bpf/xskmap.c @@ -154,7 +154,7 @@ void __xsk_map_flush(struct bpf_map *map) static void *xsk_map_lookup_elem(struct bpf_map *map, void *key) { - return ERR_PTR(-EOPNOTSUPP); + return !!__xsk_map_lookup_elem(map, *(u32 *)key); } static int xsk_map_update_elem(struct bpf_map *map, void *key, void *value, diff --git a/tools/testing/selftests/bpf/verifier/prevent_map_lookup.c b/tools/testing/selftests/bpf/verifier/prevent_map_lookup.c index bbdba990fefb..da7a4b37cb98 100644 --- a/tools/testing/selftests/bpf/verifier/prevent_map_lookup.c +++ b/tools/testing/selftests/bpf/verifier/prevent_map_lookup.c @@ -28,21 +28,6 @@ .errstr = "cannot pass map_type 18 into func bpf_map_lookup_elem", .prog_type = BPF_PROG_TYPE_SOCK_OPS, }, -{ - "prevent map lookup in xskmap", - .insns = { - BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), - BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), - BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), - BPF_LD_MAP_FD(BPF_REG_1, 0), - BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), - BPF_EXIT_INSN(), - }, - .fixup_map_xskmap = { 3 }, - .result = REJECT, - .errstr = "cannot pass map_type 17 into func bpf_map_lookup_elem", - .prog_type = BPF_PROG_TYPE_XDP, -}, { "prevent map lookup in stack trace", .insns = {