From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1131037-1520492406-2-9270694054304449291 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES enro, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='com', MailFrom='org', XOriginatingCountry='US' X-Spam-charsets: plain='iso-8859-1' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1520492405; b=K4vBDownZ98LW4mJjZEQrVnbfHCyiRU5feh4ePxzvHui2CS 8YPjEe/1VTqO0WCJWGgDdg/oHYn964nQqkmc4X80qdvfgnNjDI8vmteWe4xfIw2d t/qG+fWEM851ubfyY1DvnXHXchE4/iLNLKm+m/hba9brRo6fHfqnjrU5xNuQXQB+ dKMEDuIHq1Yb5hMDhzQtamOx9TLw9M/D4JYm6icNGC2xEF43O8KqHujKKl3v4mc+ UIlhhq4VyGFQPNJh/qBcO8+5yAEC86sMXD0/zCi0Sd0pKsbPquIdoNBfJcP87S62 p98iPwslAkCFaFoFzL2aD9OcOJy+ZhfeSnArTlw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :references:in-reply-to:content-type:content-transfer-encoding :mime-version:sender:list-id; s=arctest; t=1520492405; bh=9eEQM/ QfMUrr/ua5okJaWIJyZz5jaBILPUSeBy3r0VY=; b=LoLlSw3jw4OjKnpcZgtk5i hoOe3y5z3ptDBpKpWZbe/+8UFFpEZN6oCcOBG0s+vAjVk6ZG//f4yb+FfI16JtoL h2q1QmmJzmrqnMmIohM+P2ZmgtMXccw1xSzdKOO+vJj5UUnVRCrzM5E2XVC0PLDv brZ/23MLtEmDKFK4fgydDuhnucpJ/FQpDuI1d4HgA6NQKjrL37LYeKd3MraQXupe /V3ceQoN6J/tGzntKa5y9oeKg5qNUL4Pya61Zdkrz/yt3UC0tTBHgk14+jff+EV5 cD/5gu/lICRI/X1+FAQTmO6LqhQxJmPr3cSRT9+E8FUUmvAP3NoAZUwHHwWecSIw == ARC-Authentication-Results: i=1; mx6.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=microsoft.com header.i=@microsoft.com header.b=mTbbuFUq x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=selector1; dmarc=pass (p=reject,has-list-id=yes,d=none) header.from=microsoft.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=microsoft.com header.result=pass header_is_org_domain=yes Authentication-Results: mx6.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=microsoft.com header.i=@microsoft.com header.b=mTbbuFUq x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=selector1; dmarc=pass (p=reject,has-list-id=yes,d=none) header.from=microsoft.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=microsoft.com header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935045AbeCHHAC (ORCPT ); Thu, 8 Mar 2018 02:00:02 -0500 Received: from mail-bn3nam01on0119.outbound.protection.outlook.com ([104.47.33.119]:51237 "EHLO NAM01-BN3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934995AbeCHE5V (ORCPT ); Wed, 7 Mar 2018 23:57:21 -0500 From: Sasha Levin To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" CC: Yonghong Song , Daniel Borkmann , Sasha Levin Subject: [PATCH AUTOSEL for 4.15 45/78] bpf/cgroup: fix a verification error for a CGROUP_DEVICE type prog Thread-Topic: [PATCH AUTOSEL for 4.15 45/78] bpf/cgroup: fix a verification error for a CGROUP_DEVICE type prog Thread-Index: AQHTtpnNk1GoKJML+06VaB0E0WOz9g== Date: Thu, 8 Mar 2018 04:56:21 +0000 Message-ID: <20180308045525.7662-45-alexander.levin@microsoft.com> References: <20180308045525.7662-1-alexander.levin@microsoft.com> In-Reply-To: <20180308045525.7662-1-alexander.levin@microsoft.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [52.168.54.252] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;DM5PR2101MB1079;20:98Rcd5M+4Ckay6PrD3SNX2RD1Z2SgBBUzOuEimk6J6zhX828iw1tYnilR4GEHbWG8nDDlyiAljfT+IYkjy6R/eSE78resROSow3wjp1lCBOe263yXDCOX7xeBQBx4uDWfOm0Qt2+Mo+IqRUAtnAnuxsOGaErC8A48Dh9zPAJ62E= x-ms-office365-filtering-ht: Tenant x-ms-office365-filtering-correlation-id: 8a3eb4f1-1d33-42cd-e7c7-08d584b10d05 x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:(7020095)(4652020)(48565401081)(5600026)(4604075)(3008032)(4534165)(4627221)(201703031133081)(201702281549075)(2017052603328)(7193020);SRVR:DM5PR2101MB1079; x-ms-traffictypediagnostic: DM5PR2101MB1079: authentication-results: spf=none (sender IP is ) smtp.mailfrom=Alexander.Levin@microsoft.com; x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(28532068793085)(89211679590171)(67672495146484); x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(8211001083)(61425038)(6040501)(2401047)(8121501046)(5005006)(3231220)(944501244)(52105095)(93006095)(93001095)(10201501046)(3002001)(6055026)(61426038)(61427038)(6041288)(20161123564045)(20161123560045)(20161123558120)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(20161123562045)(6072148)(201708071742011);SRVR:DM5PR2101MB1079;BCL:0;PCL:0;RULEID:;SRVR:DM5PR2101MB1079; x-forefront-prvs: 060503E79B x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(376002)(39860400002)(39380400002)(396003)(346002)(366004)(189003)(199004)(36756003)(107886003)(4326008)(97736004)(2906002)(2950100002)(1076002)(6666003)(105586002)(7736002)(186003)(3660700001)(5660300001)(106356001)(305945005)(6512007)(3280700002)(25786009)(14454004)(575784001)(86362001)(86612001)(81156014)(10090500001)(76176011)(26005)(99286004)(66066001)(102836004)(110136005)(81166006)(72206003)(54906003)(5250100002)(478600001)(59450400001)(10290500003)(6116002)(2501003)(8936002)(68736007)(53936002)(6506007)(6486002)(8676002)(6436002)(3846002)(22452003)(316002)(2900100001)(22906009)(217873001);DIR:OUT;SFP:1102;SCL:1;SRVR:DM5PR2101MB1079;H:DM5PR2101MB1032.namprd21.prod.outlook.com;FPR:;SPF:None;PTR:InfoNoRecords;MX:1;A:1;LANG:en; x-microsoft-antispam-message-info: xEFjM4wXPMNu7VjKqhcK5GYMNv9w+SF310ShSI9suWHcD75qcWDj1qFnM1YC5UA6Io40FEmG2zaNmfZSwz/65xt0QCQB72zpJ0RAl8sFfK9EG6efI4/wcTtJeveqFNoM4S1erY72bX+4QXnPyWNTM6meTcgKTPMDXck4uJn2RLQWn/F+B7oSnqSi7rphInRwmpOCP6/3BcLUOW2nDSlTVke4wug873IB6evnakFDOg8nWpaCB2px1wr2ryKHAOku69FLbmXko7OJemorDLfe7umhJMVBWPVKr70zvgoD7GJQmuC4oJqXazTiAwBbYkat/DCiGRiSkQPdeV1PTwzwKg== spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8a3eb4f1-1d33-42cd-e7c7-08d584b10d05 X-MS-Exchange-CrossTenant-originalarrivaltime: 08 Mar 2018 04:56:21.2697 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR2101MB1079 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: From: Yonghong Song [ Upstream commit 06ef0ccb5a36e1feba9b413ff59a04ecc4407c1c ] The tools/testing/selftests/bpf test program test_dev_cgroup fails with the following error when compiled with llvm 6.0. (I did not try with earlier versions.) libbpf: load bpf program failed: Permission denied libbpf: -- BEGIN DUMP LOG --- libbpf: 0: (61) r2 =3D *(u32 *)(r1 +4) 1: (b7) r0 =3D 0 2: (55) if r2 !=3D 0x1 goto pc+8 R0=3Dinv0 R1=3Dctx(id=3D0,off=3D0,imm=3D0) R2=3Dinv1 R10=3Dfp0 3: (69) r2 =3D *(u16 *)(r1 +0) invalid bpf_context access off=3D0 size=3D2 ... The culprit is the following statement in dev_cgroup.c: short type =3D ctx->access_type & 0xFFFF; This code is typical as the ctx->access_type is assigned as below in kernel/bpf/cgroup.c: struct bpf_cgroup_dev_ctx ctx =3D { .access_type =3D (access << 16) | dev_type, .major =3D major, .minor =3D minor, }; The compiler converts it to u16 access while the verifier cgroup_dev_is_valid_access rejects any non u32 access. This patch permits the field access_type to be accessible with type u16 and u8 as well. Signed-off-by: Yonghong Song Tested-by: Roman Gushchin Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin --- include/uapi/linux/bpf.h | 3 ++- kernel/bpf/cgroup.c | 15 +++++++++++++-- 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 4c223ab30293..04b2f613dd06 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -995,7 +995,8 @@ struct bpf_perf_event_value { #define BPF_DEVCG_DEV_CHAR (1ULL << 1) =20 struct bpf_cgroup_dev_ctx { - __u32 access_type; /* (access << 16) | type */ + /* access_type encoded as (BPF_DEVCG_ACC_* << 16) | BPF_DEVCG_DEV_* */ + __u32 access_type; __u32 major; __u32 minor; }; diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index b789ab78d28f..c1c0b60d3f2f 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -568,6 +568,8 @@ static bool cgroup_dev_is_valid_access(int off, int siz= e, enum bpf_access_type type, struct bpf_insn_access_aux *info) { + const int size_default =3D sizeof(__u32); + if (type =3D=3D BPF_WRITE) return false; =20 @@ -576,8 +578,17 @@ static bool cgroup_dev_is_valid_access(int off, int si= ze, /* The verifier guarantees that size > 0. */ if (off % size !=3D 0) return false; - if (size !=3D sizeof(__u32)) - return false; + + switch (off) { + case bpf_ctx_range(struct bpf_cgroup_dev_ctx, access_type): + bpf_ctx_record_field_size(info, size_default); + if (!bpf_ctx_narrow_access_ok(off, size, size_default)) + return false; + break; + default: + if (size !=3D size_default) + return false; + } =20 return true; } --=20 2.14.1