From patchwork Tue Oct 12 02:25:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilya Leoshkevich X-Patchwork-Id: 12551309 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 149C0C433EF for ; Tue, 12 Oct 2021 02:25:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDE7560ED4 for ; Tue, 12 Oct 2021 02:25:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231511AbhJLC1u (ORCPT ); Mon, 11 Oct 2021 22:27:50 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:40530 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230330AbhJLC1u (ORCPT ); Mon, 11 Oct 2021 22:27:50 -0400 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 19C1fw1s025492; Mon, 11 Oct 2021 22:25:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=x2KQzJhA10AcPNvYpnmodgQFjizHCTQf3PCDAxTy1WM=; b=ql5+4BWK6webJzD+505D++pfdZylhrFAc2ge7aHeeLGkPyXWepZ2BrUKf3KHMx5XSNfd tT7a/IVQ35Ki0a8uyz2x1tbmi6nuL4vuOOpJS6vKGWxYTiH6gOU+8qKp7N56LjUljZHg a9r7oUEallnNi02rdoxogvKuK8vHMCWgNZrpWHu5GLYadnXgdaS0DmzgvW6hj89jG4vs nlQ0qYAlI5EanpYuVCK7LPZy5nH/qFz9WVU705fMGJdQVi5aDWXSVOq5tmRQwqR5YLgS rQcjX8LZVpbz3bgTigQs/eu8nLGUmqrdwjNrP3+SqX9JCGMG8Ajf9vIF723NacTH2qOx 9Q== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 3bn0x2gjxn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 11 Oct 2021 22:25:36 -0400 Received: from m0098410.ppops.net (m0098410.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 19C29kRi005598; Mon, 11 Oct 2021 22:25:36 -0400 Received: from ppma04ams.nl.ibm.com (63.31.33a9.ip4.static.sl-reverse.com [169.51.49.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 3bn0x2gjwx-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 11 Oct 2021 22:25:36 -0400 Received: from pps.filterd (ppma04ams.nl.ibm.com [127.0.0.1]) by ppma04ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 19C2BKdt030494; Tue, 12 Oct 2021 02:25:33 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma04ams.nl.ibm.com with ESMTP id 3bk2q9ucvu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 12 Oct 2021 02:25:33 +0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 19C2PNV845547954 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 12 Oct 2021 02:25:24 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E24FBAE04D; Tue, 12 Oct 2021 02:25:23 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 83A7EAE053; Tue, 12 Oct 2021 02:25:23 +0000 (GMT) Received: from vm.lan (unknown [9.145.45.184]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 12 Oct 2021 02:25:23 +0000 (GMT) From: Ilya Leoshkevich To: Arnaldo Carvalho de Melo Cc: dwarves@vger.kernel.org, bpf@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Heiko Carstens , Vasily Gorbik , Ilya Leoshkevich Subject: [PATCH dwarves] dwarf_loader: Fix heap overflow when accessing variable specification Date: Tue, 12 Oct 2021 04:25:21 +0200 Message-Id: <20211012022521.399302-1-iii@linux.ibm.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: yJ_qDGhtx0rtpdP5Yd7P3SJ_qBl-pmfP X-Proofpoint-GUID: 9gZqsy3IhvsdQEOqb5FH_vOwE4lX-quG X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.182.1,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.0.607.475 definitions=2021-10-11_11,2021-10-11_01,2020-04-07_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 clxscore=1011 mlxlogscore=999 adultscore=0 malwarescore=0 phishscore=0 priorityscore=1501 bulkscore=0 lowpriorityscore=0 suspectscore=0 impostorscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2109230001 definitions=main-2110120006 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Variables can be allocated with or without specification, however, tag__recode_dwarf_type() always tries accessing it, leading to heap read overflows and subsequent logic bugs. Fix by introducing a bit that tracks whether or not specification is present. Signed-off-by: Ilya Leoshkevich --- dwarf_loader.c | 15 ++++++++++----- dwarves.h | 1 + 2 files changed, 11 insertions(+), 5 deletions(-) diff --git a/dwarf_loader.c b/dwarf_loader.c index 48e1bf0..60bdca3 100644 --- a/dwarf_loader.c +++ b/dwarf_loader.c @@ -723,6 +723,7 @@ static struct variable *variable__new(Dwarf_Die *die, struct cu *cu, struct conf var->external = dwarf_hasattr(die, DW_AT_external); /* non-defining declaration of an object */ var->declaration = dwarf_hasattr(die, DW_AT_declaration); + var->has_specification = has_specification; var->scope = VSCOPE_UNKNOWN; INIT_LIST_HEAD(&var->annots); var->ip.addr = 0; @@ -2291,12 +2292,16 @@ static int tag__recode_dwarf_type(struct tag *tag, struct cu *cu) goto find_type; case DW_TAG_variable: { struct variable *var = tag__variable(tag); - dwarf_off_ref specification = dwarf_tag__spec(dtag); - if (specification.off) { - dtype = dwarf_cu__find_tag_by_ref(cu->priv, &specification); - if (dtype) - var->spec = tag__variable(dtype->tag); + if (var->has_specification) { + dwarf_off_ref specification = dwarf_tag__spec(dtag); + + if (specification.off) { + dtype = dwarf_cu__find_tag_by_ref(cu->priv, + &specification); + if (dtype) + var->spec = tag__variable(dtype->tag); + } } } diff --git a/dwarves.h b/dwarves.h index 30d33fa..20608dd 100644 --- a/dwarves.h +++ b/dwarves.h @@ -691,6 +691,7 @@ struct variable { const char *name; uint8_t external:1; uint8_t declaration:1; + uint8_t has_specification:1; enum vscope scope; struct location location; struct hlist_node tool_hnode;