From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:60637) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UVeG1-0005QV-Ef for qemu-devel@nongnu.org; Fri, 26 Apr 2013 04:43:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UVeG0-0007PY-0x for qemu-devel@nongnu.org; Fri, 26 Apr 2013 04:43:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34781) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UVeFz-0007PT-PT for qemu-devel@nongnu.org; Fri, 26 Apr 2013 04:43:51 -0400 From: Jason Wang Date: Fri, 26 Apr 2013 16:34:03 +0800 Message-Id: <1366965244-20542-2-git-send-email-jasowang@redhat.com> In-Reply-To: <1366965244-20542-1-git-send-email-jasowang@redhat.com> References: <1366965244-20542-1-git-send-email-jasowang@redhat.com> Subject: [Qemu-devel] [PATCH 2/3] virtio-ccw: check config length before accessing it List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: aliguori@us.ibm.com, mst@redhat.com, qemu-devel@nongnu.org Cc: Cornelia Huck , Jason Wang , pmatouse@redhat.com, Alexander Graf , Richard Henderson virtio-rng-ccw has zero config length, so we need validate the config length before trying to access it. Otherwise we may crash since vdev->config is NULL. Cc: Cornelia Huck Cc: Richard Henderson Cc: Alexander Graf Signed-off-by: Jason Wang --- hw/s390x/virtio-ccw.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c index 56539d3..8d0dff5 100644 --- a/hw/s390x/virtio-ccw.c +++ b/hw/s390x/virtio-ccw.c @@ -260,7 +260,7 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) } } len = MIN(ccw.count, dev->vdev->config_len); - if (!ccw.cda) { + if (!ccw.cda || !len) { ret = -EFAULT; } else { dev->vdev->get_config(dev->vdev, dev->vdev->config); @@ -279,7 +279,7 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) } len = MIN(ccw.count, dev->vdev->config_len); hw_len = len; - if (!ccw.cda) { + if (!ccw.cda || !len) { ret = -EFAULT; } else { config = cpu_physical_memory_map(ccw.cda, &hw_len, 0); -- 1.7.1