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 9D88DC432C0 for ; Mon, 25 Nov 2019 10:35:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 704732082F for ; Mon, 25 Nov 2019 10:35:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="dyy2ZVwk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727471AbfKYKfs (ORCPT ); Mon, 25 Nov 2019 05:35:48 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:30049 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727266AbfKYKfr (ORCPT ); Mon, 25 Nov 2019 05:35:47 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1574678146; 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=ZMYkA3jI8+ywNR+OhV3jpIlPger7eOA5dEPy09p1d6E=; b=dyy2ZVwk9P1P6CI6YlUeRdXMkmj6h6DHx9ZsORsqi1X17W72/3ZEjvkJOIvgx3m9ld2TXV Uvtq8M8mdf6s9NdiPIamRF7qrZUtQGpUBdMiDlZld3P9c/skUY258gtks+g2R5ODR2/shS +qQELQDJeZOF1C3S/b5fbyYkOe8Q2/o= 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-337-8pbgYF59MamGTDCxyCAzoQ-1; Mon, 25 Nov 2019 05:35:45 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 10B44107B765; Mon, 25 Nov 2019 10:35:44 +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 8C39319C69; Mon, 25 Nov 2019 10:35:39 +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] iommu: fix KASAN use-after-free in iommu_insert_resv_region Date: Mon, 25 Nov 2019 11:35:35 +0100 Message-Id: <20191125103535.22782-1-eric.auger@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: 8pbgYF59MamGTDCxyCAzoQ-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+ --- drivers/iommu/iommu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index d658c7c6a2ab..338769f96d17 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -293,6 +293,8 @@ 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 +315,7 @@ 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