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=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 0F010C352AA for ; Wed, 2 Oct 2019 01:45:14 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D291E20842 for ; Wed, 2 Oct 2019 01:45:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D291E20842 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:50336 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iFThY-0007H7-Oz for qemu-devel@archiver.kernel.org; Tue, 01 Oct 2019 21:45:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41532) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iFRsw-0002JP-Oq for qemu-devel@nongnu.org; Tue, 01 Oct 2019 19:48:52 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iFRss-00037r-RV for qemu-devel@nongnu.org; Tue, 01 Oct 2019 19:48:48 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51988 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iFRsg-0002D1-PW; Tue, 01 Oct 2019 19:48:35 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x91NlX3d146488; Tue, 1 Oct 2019 19:48:04 -0400 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vcfcp26q6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 01 Oct 2019 19:48:04 -0400 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x91NjkEb027150; Tue, 1 Oct 2019 23:48:03 GMT Received: from b01cxnp23032.gho.pok.ibm.com (b01cxnp23032.gho.pok.ibm.com [9.57.198.27]) by ppma03dal.us.ibm.com with ESMTP id 2v9y587bk2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 01 Oct 2019 23:48:03 +0000 Received: from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com [9.57.199.106]) by b01cxnp23032.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x91Nm3As38535662 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 1 Oct 2019 23:48:03 GMT Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 104CA28059; Tue, 1 Oct 2019 23:48:03 +0000 (GMT) Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E88B12805C; Tue, 1 Oct 2019 23:48:02 +0000 (GMT) Received: from localhost (unknown [9.53.179.213]) by b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP; Tue, 1 Oct 2019 23:48:02 +0000 (GMT) From: Michael Roth To: qemu-devel@nongnu.org Subject: [PATCH 93/97] slirp: Fix heap overflow in ip_reass on big packet input Date: Tue, 1 Oct 2019 18:46:12 -0500 Message-Id: <20191001234616.7825-94-mdroth@linux.vnet.ibm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191001234616.7825-1-mdroth@linux.vnet.ibm.com> References: <20191001234616.7825-1-mdroth@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-10-01_10:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 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=8.0.1-1908290000 definitions=main-1910010203 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Samuel Thibault , qemu-stable@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" When the first fragment does not fit in the preallocated buffer, q will already be pointing to the ext buffer, so we mustn't try to update it. Signed-off-by: Samuel Thibault (from libslirp.git commit 126c04acbabd7ad32c2b018fe10dfac2a3bc1210) (from libslirp.git commit e0be80430c390bce181ea04dfcdd6ea3dfa97de1) *squash in e0be80 (clarifying comments) Signed-off-by: Michael Roth --- slirp/src/ip_input.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/slirp/src/ip_input.c b/slirp/src/ip_input.c index a714fecd58..68a99de5b5 100644 --- a/slirp/src/ip_input.c +++ b/slirp/src/ip_input.c @@ -331,6 +331,8 @@ insert: q = fp->frag_link.next; m = dtom(slirp, q); + int was_ext = m->m_flags & M_EXT; + q = (struct ipasfrag *) q->ipf_next; while (q != (struct ipasfrag*)&fp->frag_link) { struct mbuf *t = dtom(slirp, q); @@ -347,13 +349,12 @@ insert: q = fp->frag_link.next; /* - * If the fragments concatenated to an mbuf that's - * bigger than the total size of the fragment, then and - * m_ext buffer was alloced. But fp->ipq_next points to - * the old buffer (in the mbuf), so we must point ip - * into the new buffer. + * If the fragments concatenated to an mbuf that's bigger than the total + * size of the fragment and the mbuf was not already using an m_ext buffer, + * then an m_ext buffer was alloced. But fp->ipq_next points to the old + * buffer (in the mbuf), so we must point ip into the new buffer. */ - if (m->m_flags & M_EXT) { + if (!was_ext && m->m_flags & M_EXT) { int delta = (char *)q - m->m_dat; q = (struct ipasfrag *)(m->m_ext + delta); } -- 2.17.1