From mboxrd@z Thu Jan 1 00:00:00 1970 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AD326ECAAD5 for ; Mon, 5 Sep 2022 04:55:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229560AbiIEEzF (ORCPT ); Mon, 5 Sep 2022 00:55:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235806AbiIEEzE (ORCPT ); Mon, 5 Sep 2022 00:55:04 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E61F21837 for ; Sun, 4 Sep 2022 21:55:02 -0700 (PDT) Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 28541KH4018626; Mon, 5 Sep 2022 04:54:54 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=3Mu2d0c6v8vZ6us4SFYqeK9NDC6MEcp3sH5VFKCno6k=; b=AAJSHRe5YtCLAqsvn3xUT09h9q0rjiej+urAh6LVOx/17glTJpLVBxEHI0Lx+riWz54Q rdK0h7qbsbJBjWI0neOfmxsJ9nOqqiDsm607HD9pIQ/3vJg4A5fwhLj3h7P6NFgYSImK l4afmTsoR5JlvEd4wrU+zkdb0h+7H8opkgTVi15bGAQJIzYZWGBU9oKIq9Ax5I2DALba jY7eSePqiQNd53N9yYW2zqUqir6vZsUewNGvcmQRIbZVmuqP8BcIGLtn4hQv/f5DqSVj iocldWKnPtRDrRvJezdDt6/OtFk/LqZ4GHQTfmBQezvdh+/NkbaNewjZ06b1LSBz8DYp hA== Received: from ppma04ams.nl.ibm.com (63.31.33a9.ip4.static.sl-reverse.com [169.51.49.99]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3jd845tt37-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 05 Sep 2022 04:54:54 +0000 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 2854o37g024829; Mon, 5 Sep 2022 04:54:52 GMT Received: from b06avi18878370.portsmouth.uk.ibm.com (b06avi18878370.portsmouth.uk.ibm.com [9.149.26.194]) by ppma04ams.nl.ibm.com with ESMTP id 3jbxj8sw05-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 05 Sep 2022 04:54:52 +0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 2854tCrp45023512 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 5 Sep 2022 04:55:12 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E07DEA4040; Mon, 5 Sep 2022 04:54:48 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E5F41A4051; Mon, 5 Sep 2022 04:54:46 +0000 (GMT) Received: from localhost.localdomain (unknown [9.43.52.217]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 5 Sep 2022 04:54:46 +0000 (GMT) From: Athira Rajeev To: acme@kernel.org, jolsa@kernel.org Cc: mpe@ellerman.id.au, linux-perf-users@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, maddy@linux.vnet.ibm.com, rnsastry@linux.ibm.com, kjain@linux.ibm.com Subject: [PATCH 2/2] tools/perf: Fix out of bound access to cpu mask array Date: Mon, 5 Sep 2022 10:24:41 +0530 Message-Id: <20220905045441.1643-2-atrajeev@linux.vnet.ibm.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220905045441.1643-1-atrajeev@linux.vnet.ibm.com> References: <20220905045441.1643-1-atrajeev@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: Ysz9oca1HPlZCoCmOZBhRMfoKoJyoRA8 X-Proofpoint-GUID: Ysz9oca1HPlZCoCmOZBhRMfoKoJyoRA8 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-09-05_02,2022-08-31_03,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 bulkscore=0 spamscore=0 mlxscore=0 phishscore=0 priorityscore=1501 lowpriorityscore=0 malwarescore=0 mlxlogscore=999 impostorscore=0 adultscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2209050020 Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org The cpu mask init code in "record__mmap_cpu_mask_init" function access "bits" array part of "struct mmap_cpu_mask". The size of this array is the value from cpu__max_cpu().cpu. This array is used to contain the cpumask value for each cpu. While setting bit for each cpu, it calls "set_bit" function which access index in "bits" array. If we provide a command line option to -C which is greater than the number of CPU's present in the system, the set_bit could access an array member which is out-of the array size. This is because currently, there is no boundary check for the CPU. This will result in seg fault: <<>> ./perf record -C 12341234 ls Perf can support 2048 CPUs. Consider raising MAX_NR_CPUS Segmentation fault (core dumped) <<>> Debugging with gdb, points to function flow as below: <<>> set_bit record__mmap_cpu_mask_init record__init_thread_default_masks record__init_thread_masks cmd_record <<>> Fix this by adding boundary check for the array. After the patch: <<>> ./perf record -C 12341234 ls Perf can support 2048 CPUs. Consider raising MAX_NR_CPUS Failed to initialize parallel data streaming masks <<>> With this fix, if -C is given a non-exsiting CPU, perf record will fail with: <<>> ./perf record -C 50 ls Failed to initialize parallel data streaming masks <<>> Reported-by: Nageswara Sastry Signed-off-by: Athira Rajeev --- tools/perf/builtin-record.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 4713f0f3a6cf..09b68d76bbdc 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -3358,16 +3358,22 @@ static struct option __record_options[] = { struct option *record_options = __record_options; -static void record__mmap_cpu_mask_init(struct mmap_cpu_mask *mask, struct perf_cpu_map *cpus) +static int record__mmap_cpu_mask_init(struct mmap_cpu_mask *mask, struct perf_cpu_map *cpus) { struct perf_cpu cpu; int idx; if (cpu_map__is_dummy(cpus)) - return; + return 0; - perf_cpu_map__for_each_cpu(cpu, idx, cpus) + perf_cpu_map__for_each_cpu(cpu, idx, cpus) { + /* Return ENODEV is input cpu is greater than max cpu */ + if ((unsigned long)cpu.cpu > mask->nbits) + return -ENODEV; set_bit(cpu.cpu, mask->bits); + } + + return 0; } static int record__mmap_cpu_mask_init_spec(struct mmap_cpu_mask *mask, const char *mask_spec) @@ -3379,7 +3385,9 @@ static int record__mmap_cpu_mask_init_spec(struct mmap_cpu_mask *mask, const cha return -ENOMEM; bitmap_zero(mask->bits, mask->nbits); - record__mmap_cpu_mask_init(mask, cpus); + if (record__mmap_cpu_mask_init(mask, cpus)) + return -ENODEV; + perf_cpu_map__put(cpus); return 0; @@ -3461,7 +3469,12 @@ static int record__init_thread_masks_spec(struct record *rec, struct perf_cpu_ma pr_err("Failed to allocate CPUs mask\n"); return ret; } - record__mmap_cpu_mask_init(&cpus_mask, cpus); + + ret = record__mmap_cpu_mask_init(&cpus_mask, cpus); + if (ret) { + pr_err("Failed to init cpu mask\n"); + goto out_free_cpu_mask; + } ret = record__thread_mask_alloc(&full_mask, cpu__max_cpu().cpu); if (ret) { @@ -3702,7 +3715,8 @@ static int record__init_thread_default_masks(struct record *rec, struct perf_cpu if (ret) return ret; - record__mmap_cpu_mask_init(&rec->thread_masks->maps, cpus); + if (record__mmap_cpu_mask_init(&rec->thread_masks->maps, cpus)) + return -ENODEV; rec->nr_threads = 1; -- 2.35.1