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=-6.9 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 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 1A58DC432C0 for ; Mon, 25 Nov 2019 10:45:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D205420740 for ; Mon, 25 Nov 2019 10:45:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="MiQIPV7W" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727563AbfKYKpS (ORCPT ); Mon, 25 Nov 2019 05:45:18 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:47852 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727278AbfKYKpS (ORCPT ); Mon, 25 Nov 2019 05:45:18 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1574678717; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=QRAeg6sofwTZ7IMOF1+XpMax8/HjXNDIA5l6w+nYTIs=; b=MiQIPV7WY78DFrcwTLEFCLGG0+YKVikAB3LmB0hKEHK0tLAwf0FlQs+Xom00MJ44Zs3qMN ji71qeI/0+AVip8d1qFo1m7Z/OIqroRyNK5xoBOjlh+/Cim1D1v9HDqG7tXAm6+25bwci5 lUT5FxcdALcGSZ4PGMAtFxAeRJpjbN4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-174-N6dA0LuNPl2MuZqUDdLEIA-1; Mon, 25 Nov 2019 05:45:16 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 05DBC80058E; Mon, 25 Nov 2019 10:45:15 +0000 (UTC) Received: from laptop.redhat.com (ovpn-116-37.ams2.redhat.com [10.36.116.37]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8E9665C1D4; Mon, 25 Nov 2019 10:45:10 +0000 (UTC) From: Eric Auger To: eric.auger.pro@gmail.com, eric.auger@redhat.com, joro@8bytes.org, hch@lst.de, cai@lca.pw, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] iommu: fix KASAN use-after-free in iommu_insert_resv_region Date: Mon, 25 Nov 2019 11:45:07 +0100 Message-Id: <20191125104507.23704-1-eric.auger@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-MC-Unique: N6dA0LuNPl2MuZqUDdLEIA-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Store the new region type in a variable. In case the new region gets merged into another one, the new node is freed and nr shall not be used anymore. Fixes: 4dbd258ff63e ("iommu: Revisit iommu_insert_resv_region() implementation") Signed-off-by: Eric Auger Reported-by: Qian Cai Cc: Stable #v5.3+ --- - remove spurious new line --- drivers/iommu/iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index d658c7c6a2ab..4412b876250c 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -293,6 +293,7 @@ int iommu_insert_resv_region(struct iommu_resv_region *= new, =09=09=09 struct list_head *regions) { =09struct iommu_resv_region *iter, *tmp, *nr, *top; +=09enum iommu_resv_type nr_type =3D new->type; =09LIST_HEAD(stack); =20 =09nr =3D iommu_alloc_resv_region(new->start, new->length, @@ -313,7 +314,7 @@ int iommu_insert_resv_region(struct iommu_resv_region *= new, =09=09phys_addr_t top_end, iter_end =3D iter->start + iter->length - 1; =20 =09=09/* no merge needed on elements of different types than @nr */ -=09=09if (iter->type !=3D nr->type) { +=09=09if (iter->type !=3D nr_type) { =09=09=09list_move_tail(&iter->list, &stack); =09=09=09continue; =09=09} --=20 2.20.1