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 X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8326C2D0DB for ; Fri, 24 Jan 2020 16:45:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99E042070A for ; Fri, 24 Jan 2020 16:45:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="CN94oT93" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388149AbgAXQp0 (ORCPT ); Fri, 24 Jan 2020 11:45:26 -0500 Received: from aserp2120.oracle.com ([141.146.126.78]:46834 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390424AbgAXQpZ (ORCPT ); Fri, 24 Jan 2020 11:45:25 -0500 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id 00OGhdOe163796; Fri, 24 Jan 2020 16:44:44 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2019-08-05; bh=ax2b7VbroDAFXGhWoaT8oid295EG/aT8E5ybilKIp/8=; b=CN94oT93dmhc59Evrew/6dj3KVkcSKW1kn1ZvYwtt43WNbD+VI5MjX6T4CZT7ftmrbvh Q4fxTieCq3Og6dbIv8Wg9RbW+aOdYg+8GljZKz8G3rFHJLktSHPCvk45bWzrFVZJlUVc phZikyy4/F7ZtjOGfcYiOnjr+EImiYPLDZUSupjSsWaHqCt/LIIo7IfonjQAbDS1Axs9 fbWaaRRdKqkHCxwerYXHFBMx/wUVzbIAENpu4UhWK83/4Q8SlouEXgMeG98PF/9Lh3Ic 9XKNG2dH/jr7nadHTuDvckoTx+tPqm6SEHyvlwVU0pBofGnvzu5ixATxUyQe8ipHV+kx qw== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by aserp2120.oracle.com with ESMTP id 2xksyqt3hu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 24 Jan 2020 16:44:43 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id 00OGi8rW142590; Fri, 24 Jan 2020 16:44:43 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3030.oracle.com with ESMTP id 2xqmufc49n-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 24 Jan 2020 16:44:43 +0000 Received: from abhmp0015.oracle.com (abhmp0015.oracle.com [141.146.116.21]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 00OGif1t004136; Fri, 24 Jan 2020 16:44:41 GMT Received: from kadam (/129.205.23.165) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 24 Jan 2020 08:44:40 -0800 Date: Fri, 24 Jan 2020 19:44:27 +0300 From: Dan Carpenter To: Anton Ivanov Cc: Jeff Dike , Song Liu , Daniel Borkmann , kernel-janitors@vger.kernel.org, Richard Weinberger , linux-um@lists.infradead.org, Alexei Starovoitov , Alex Dewar , Yonghong Song , bpf@vger.kernel.org, Andrii Nakryiko , Martin KaFai Lau Subject: Re: [PATCH] um: Fix some error handling in uml_vector_user_bpf() Message-ID: <20200124164427.GF1870@kadam> References: <20200124101450.jxfzsh6sz7v324hv@kili.mountain> <36070c96-8e75-7d06-d945-87a9d366d0b9@cambridgegreys.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <36070c96-8e75-7d06-d945-87a9d366d0b9@cambridgegreys.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9510 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1911140001 definitions=main-2001240137 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9510 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1911140001 definitions=main-2001240137 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Fri, Jan 24, 2020 at 12:52:18PM +0000, Anton Ivanov wrote: > > > On 24/01/2020 10:14, Dan Carpenter wrote: > > 1) The uml_vector_user_bpf() returns pointers so it should return NULL > > instead of false. > > 2) If the "bpf_prog" allocation failed, it would have eventually lead to > > a crash. We can't succeed after the error happens so it should just > > return. > > > > Fixes: 9807019a62dc ("um: Loadable BPF "Firmware" for vector drivers") > > Signed-off-by: Dan Carpenter > > --- > > arch/um/drivers/vector_user.c | 10 +++++----- > > 1 file changed, 5 insertions(+), 5 deletions(-) > > > > diff --git a/arch/um/drivers/vector_user.c b/arch/um/drivers/vector_user.c > > index ddcd917be0af..88483f5b034c 100644 > > --- a/arch/um/drivers/vector_user.c > > +++ b/arch/um/drivers/vector_user.c > > @@ -732,13 +732,13 @@ void *uml_vector_user_bpf(char *filename) > > if (stat(filename, &statbuf) < 0) { > > printk(KERN_ERR "Error %d reading bpf file", -errno); > > - return false; > > + return NULL; > > I will sort this one out, thanks for noticing. > > > } > > bpf_prog = uml_kmalloc(sizeof(struct sock_fprog), UM_GFP_KERNEL); > > - if (bpf_prog != NULL) { > > - bpf_prog->len = statbuf.st_size / sizeof(struct sock_filter); > > - bpf_prog->filter = NULL; > > - } > > + if (!pfg_prog) > > ^^^^^ ? If we don't return here it leads to a NULL dereference. regards, dan carpenter