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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 0D816C3F2CD for ; Mon, 23 Mar 2020 13:29:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CBE6B20735 for ; Mon, 23 Mar 2020 13:29:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CBE6B20735 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 62FCF6B0007; Mon, 23 Mar 2020 09:29:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 591566B0008; Mon, 23 Mar 2020 09:29:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4804E6B000A; Mon, 23 Mar 2020 09:29:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0041.hostedemail.com [216.40.44.41]) by kanga.kvack.org (Postfix) with ESMTP id 314306B0007 for ; Mon, 23 Mar 2020 09:29:48 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 4056B1F10 for ; Mon, 23 Mar 2020 13:29:48 +0000 (UTC) X-FDA: 76626709656.09.mice94_1b4c536989a29 X-HE-Tag: mice94_1b4c536989a29 X-Filterd-Recvd-Size: 5115 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by imf36.hostedemail.com (Postfix) with ESMTP for ; Mon, 23 Mar 2020 13:29:47 +0000 (UTC) Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 02ND2pLn169642 for ; Mon, 23 Mar 2020 09:29:46 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ywejv6pr9-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 23 Mar 2020 09:29:45 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 23 Mar 2020 13:29:34 -0000 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 02NDTX8458851470 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 23 Mar 2020 13:29:33 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A39A84204C; Mon, 23 Mar 2020 13:29:33 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5994842047; Mon, 23 Mar 2020 13:29:33 +0000 (GMT) Received: from oc3871087118.ibm.com (unknown [9.145.39.189]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 23 Mar 2020 13:29:33 +0000 (GMT) From: agordeev@linux.ibm.com To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Alexander Gordeev Subject: [PATCH 2/2] mm/mmap.c: do not allow mappings outside of allowed limits Date: Mon, 23 Mar 2020 14:29:29 +0100 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: References: X-TM-AS-GCONF: 00 x-cbid: 20032313-0012-0000-0000-000003963A1B X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20032313-0013-0000-0000-000021D32A7F Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.645 definitions=2020-03-23_04:2020-03-21,2020-03-23 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 clxscore=1015 suspectscore=1 spamscore=0 mlxscore=0 mlxlogscore=441 adultscore=0 bulkscore=0 phishscore=0 lowpriorityscore=0 priorityscore=1501 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003230075 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Alexander Gordeev It is possible to request a fixed mapping address below mmap_min_addr and succeed. This update adds early checks of mmap_min_addr and mmap_end boundaries and fixes the above issue. Signed-off-by: Alexander Gordeev --- mm/mmap.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index a0fcb5ca0e06..bd673a01b1d0 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -59,6 +59,14 @@ #define arch_mmap_check(addr, len, flags) (0) #endif +#ifndef arch_get_mmap_end +#define arch_get_mmap_end(addr) (TASK_SIZE) +#endif + +#ifndef arch_get_mmap_base +#define arch_get_mmap_base(addr, base) (base) +#endif + #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS const int mmap_rnd_bits_min = CONFIG_ARCH_MMAP_RND_BITS_MIN; const int mmap_rnd_bits_max = CONFIG_ARCH_MMAP_RND_BITS_MAX; @@ -1366,6 +1374,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr, unsigned long pgoff, unsigned long *populate, struct list_head *uf) { + const unsigned long mmap_end = arch_get_mmap_end(addr); struct mm_struct *mm = current->mm; int pkey = 0; @@ -1388,8 +1397,12 @@ unsigned long do_mmap(struct file *file, unsigned long addr, if (flags & MAP_FIXED_NOREPLACE) flags |= MAP_FIXED; - if (!(flags & MAP_FIXED)) + if (flags & MAP_FIXED) { + if ((addr < mmap_min_addr) || (addr > mmap_end)) + return -ENOMEM; + } else { addr = round_hint_to_min(addr); + } /* Careful about overflows.. */ len = PAGE_ALIGN(len); @@ -2050,15 +2063,6 @@ unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info) return gap_end; } - -#ifndef arch_get_mmap_end -#define arch_get_mmap_end(addr) (TASK_SIZE) -#endif - -#ifndef arch_get_mmap_base -#define arch_get_mmap_base(addr, base) (base) -#endif - /* Get an address range which is currently unmapped. * For shmat() with addr=0. * -- 2.23.0