From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38812) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cGhIk-0007Qi-49 for qemu-devel@nongnu.org; Tue, 13 Dec 2016 02:15:03 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cGhIf-0002au-7W for qemu-devel@nongnu.org; Tue, 13 Dec 2016 02:15:02 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35812) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cGhIf-0002Zt-1w for qemu-devel@nongnu.org; Tue, 13 Dec 2016 02:14:57 -0500 From: P J P Date: Tue, 13 Dec 2016 12:44:39 +0530 Message-Id: <20161213071439.32322-1-ppandit@redhat.com> Subject: [Qemu-devel] [PATCH] display: virtio-gpu-3d: check virgl capabilities max_size List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Qemu Developers Cc: Gerd Hoffmann , Zhenhao Hong , Prasad J Pandit From: Prasad J Pandit Virtio GPU device while processing 'VIRTIO_GPU_CMD_GET_CAPSET' command, retrieves the maximum capabilities size to fill in the response object. It continues to fill in capabilities even if retrieved 'max_size' is zero(0), thus resulting in OOB access. Add check to avoid it. Reported-by: Zhenhao Hong Signed-off-by: Prasad J Pandit --- hw/display/virtio-gpu-3d.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/hw/display/virtio-gpu-3d.c b/hw/display/virtio-gpu-3d.c index 758d33a..fbfb39f 100644 --- a/hw/display/virtio-gpu-3d.c +++ b/hw/display/virtio-gpu-3d.c @@ -371,11 +371,12 @@ static void virgl_cmd_get_capset(VirtIOGPU *g, virgl_renderer_get_cap_set(gc.capset_id, &max_ver, &max_size); resp = g_malloc(sizeof(*resp) + max_size); - - resp->hdr.type = VIRTIO_GPU_RESP_OK_CAPSET; - virgl_renderer_fill_caps(gc.capset_id, - gc.capset_version, - (void *)resp->capset_data); + if (max_size) { + resp->hdr.type = VIRTIO_GPU_RESP_OK_CAPSET; + virgl_renderer_fill_caps(gc.capset_id, + gc.capset_version, + (void *)resp->capset_data); + } virtio_gpu_ctrl_response(g, cmd, &resp->hdr, sizeof(*resp) + max_size); g_free(resp); } -- 2.9.3