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=-6.8 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 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 893E5C433E0 for ; Sat, 23 May 2020 17:47:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6267C20679 for ; Sat, 23 May 2020 17:47:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="AqD505EQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388253AbgEWRri (ORCPT ); Sat, 23 May 2020 13:47:38 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:56974 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387515AbgEWRrh (ORCPT ); Sat, 23 May 2020 13:47:37 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04NHfZGI061426; Sat, 23 May 2020 17:47:06 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : mime-version : content-type; s=corp-2020-01-29; bh=+K7hQZPEXSyknr5qcG7D4mkj48QK4TpEeGTcX08C/ss=; b=AqD505EQz3V9MBm8s4Q2RU8YHY/vna50cBXOf1fEDcZjDRi489GMpKosyh+oAe2+AT3v uqhenmCnBOrdBxYRl150TOZlSUTS4mHQB30bC87q46BQeWUsmq1crivMnOwKG1zMZE1H khANm2GiBbYH5e30S8lXuNfAeybzMvO4rHf6g564r53qtutLCEWvlQ70iHDtcVgERyOp dJ/asBivQhW4D7xdQHQT2rxrkhY/gzxEWo/dUuE7QomGAPDPtyK9pirklT16LFbdXIDd 2v2Nl7wqoAoIIO3tKTOiuDQ24IVY8R+ovkCvreLEOhAWZnTTRs54bW+QpOWLWLBlwNNd Zg== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2120.oracle.com with ESMTP id 316vfn16td-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Sat, 23 May 2020 17:47:05 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 04NHhKp2080621; Sat, 23 May 2020 17:47:05 GMT Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserp3020.oracle.com with ESMTP id 316un1djh2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sat, 23 May 2020 17:47:05 +0000 Received: from abhmp0003.oracle.com (abhmp0003.oracle.com [141.146.116.9]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 04NHkx1e010453; Sat, 23 May 2020 17:47:00 GMT Received: from mwanda (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sat, 23 May 2020 10:46:59 -0700 Date: Sat, 23 May 2020 20:46:48 +0300 From: Dan Carpenter To: Al Viro , "David S. Miller" Cc: Alexey Kuznetsov , Hideaki YOSHIFUJI , Jakub Kicinski , netdev@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH net-next] ipv4: potential underflow in compat_ip_setsockopt() Message-ID: <20200523174648.GA105146@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Mailer: git-send-email haha only kidding X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9630 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 bulkscore=0 mlxscore=0 malwarescore=0 phishscore=0 spamscore=0 suspectscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005230147 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9630 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 clxscore=1011 priorityscore=1501 mlxscore=0 malwarescore=0 spamscore=0 impostorscore=0 mlxlogscore=999 lowpriorityscore=0 bulkscore=0 adultscore=0 suspectscore=0 cotscore=-2147483648 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005230147 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The value of "n" is capped at 0x1ffffff but it checked for negative values. I don't think this causes a problem but I'm not certain and it's harmless to prevent it. Fixes: 2e04172875c9 ("ipv4: do compat setsockopt for MCAST_MSFILTER directly") Signed-off-by: Dan Carpenter --- net/ipv4/ip_sockglue.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index a2469bc57cfe..f43d5f12aa86 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -1347,8 +1347,8 @@ int compat_ip_setsockopt(struct sock *sk, int level, int optname, { const int size0 = offsetof(struct compat_group_filter, gf_slist); struct compat_group_filter *gf32; + unsigned int n; void *p; - int n; if (optlen < size0) return -EINVAL; -- 2.26.2