From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934217AbcKDLY0 (ORCPT ); Fri, 4 Nov 2016 07:24:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42454 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934153AbcKDLYX (ORCPT ); Fri, 4 Nov 2016 07:24:23 -0400 From: Eric Auger To: eric.auger@redhat.com, eric.auger.pro@gmail.com, christoffer.dall@linaro.org, marc.zyngier@arm.com, robin.murphy@arm.com, alex.williamson@redhat.com, will.deacon@arm.com, joro@8bytes.org, tglx@linutronix.de, jason@lakedaemon.net, linux-arm-kernel@lists.infradead.org Cc: kvm@vger.kernel.org, drjones@redhat.com, linux-kernel@vger.kernel.org, pranav.sawargaonkar@gmail.com, iommu@lists.linux-foundation.org, punit.agrawal@arm.com, diana.craciun@nxp.com Subject: [RFC v2 1/8] vfio: fix vfio_info_cap_add/shift Date: Fri, 4 Nov 2016 11:23:59 +0000 Message-Id: <1478258646-3117-2-git-send-email-eric.auger@redhat.com> In-Reply-To: <1478258646-3117-1-git-send-email-eric.auger@redhat.com> References: <1478258646-3117-1-git-send-email-eric.auger@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Fri, 04 Nov 2016 11:24:22 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Capability header next field is an offset relative to the start of the INFO buffer. tmp->next is assigned the proper value but iterations implemented in vfio_info_cap_add and vfio_info_cap_shift use next as an offset between the headers. When coping with multiple capabilities this leads to an Oops. Signed-off-by: Eric Auger --- drivers/vfio/vfio.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index d1d70e0..1e838d1 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1763,7 +1763,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, header->version = version; /* Add to the end of the capability chain */ - for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next) + for (tmp = buf; tmp->next; tmp = buf + tmp->next) ; /* nothing */ tmp->next = caps->size; @@ -1776,8 +1776,9 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset) { struct vfio_info_cap_header *tmp; + void *buf = (void *)caps->buf; - for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next - offset) + for (tmp = buf; tmp->next; tmp = buf + tmp->next - offset) tmp->next += offset; } EXPORT_SYMBOL_GPL(vfio_info_cap_shift); -- 1.9.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Auger Subject: [RFC v2 1/8] vfio: fix vfio_info_cap_add/shift Date: Fri, 4 Nov 2016 11:23:59 +0000 Message-ID: <1478258646-3117-2-git-send-email-eric.auger@redhat.com> References: <1478258646-3117-1-git-send-email-eric.auger@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: drjones-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, punit.agrawal-5wv7dgnIgG8@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, pranav.sawargaonkar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org To: eric.auger-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, eric.auger.pro-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, christoffer.dall-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, marc.zyngier-5wv7dgnIgG8@public.gmane.org, robin.murphy-5wv7dgnIgG8@public.gmane.org, alex.williamson-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, jason-NLaQJdtUoK4Be96aLqz0jA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Return-path: In-Reply-To: <1478258646-3117-1-git-send-email-eric.auger-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: kvm.vger.kernel.org Capability header next field is an offset relative to the start of the INFO buffer. tmp->next is assigned the proper value but iterations implemented in vfio_info_cap_add and vfio_info_cap_shift use next as an offset between the headers. When coping with multiple capabilities this leads to an Oops. Signed-off-by: Eric Auger --- drivers/vfio/vfio.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index d1d70e0..1e838d1 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1763,7 +1763,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, header->version = version; /* Add to the end of the capability chain */ - for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next) + for (tmp = buf; tmp->next; tmp = buf + tmp->next) ; /* nothing */ tmp->next = caps->size; @@ -1776,8 +1776,9 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset) { struct vfio_info_cap_header *tmp; + void *buf = (void *)caps->buf; - for (tmp = caps->buf; tmp->next; tmp = (void *)tmp + tmp->next - offset) + for (tmp = buf; tmp->next; tmp = buf + tmp->next - offset) tmp->next += offset; } EXPORT_SYMBOL_GPL(vfio_info_cap_shift); -- 1.9.1