From fe89fdebcaab696d525f2905b33d7b303111eade Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Date: Thu, 19 May 2016 12:25:55 +0200 Subject: [PATCH] virtio-gpu: check early scanout id MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Before accessing the g->scanout array, in order to avoid potential out-of-bounds access. Signed-off-by: Marc-André Lureau Message-id: 1463653560-26958-2-git-send-email-marcandre.lureau@redhat.com Signed-off-by: Gerd Hoffmann --- hw/display/virtio-gpu.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c index 91345bd399..64a60f25f8 100644 --- a/hw/display/virtio-gpu.c +++ b/hw/display/virtio-gpu.c @@ -508,6 +508,14 @@ static void virtio_gpu_set_scanout(VirtIOGPU *g, trace_virtio_gpu_cmd_set_scanout(ss.scanout_id, ss.resource_id, ss.r.width, ss.r.height, ss.r.x, ss.r.y); + if (ss.scanout_id >= VIRTIO_GPU_MAX_SCANOUT || + ss.scanout_id >= g->conf.max_outputs) { + qemu_log_mask(LOG_GUEST_ERROR, "%s: illegal scanout id specified %d", + __func__, ss.scanout_id); + cmd->error = VIRTIO_GPU_RESP_ERR_INVALID_SCANOUT_ID; + return; + } + g->enable = 1; if (ss.resource_id == 0) { scanout = &g->scanout[ss.scanout_id]; @@ -517,8 +525,7 @@ static void virtio_gpu_set_scanout(VirtIOGPU *g, res->scanout_bitmask &= ~(1 << ss.scanout_id); } } - if (ss.scanout_id == 0 || - ss.scanout_id >= g->conf.max_outputs) { + if (ss.scanout_id == 0) { qemu_log_mask(LOG_GUEST_ERROR, "%s: illegal scanout id specified %d", __func__, ss.scanout_id); @@ -533,14 +540,6 @@ static void virtio_gpu_set_scanout(VirtIOGPU *g, } /* create a surface for this scanout */ - if (ss.scanout_id >= VIRTIO_GPU_MAX_SCANOUT || - ss.scanout_id >= g->conf.max_outputs) { - qemu_log_mask(LOG_GUEST_ERROR, "%s: illegal scanout id specified %d", - __func__, ss.scanout_id); - cmd->error = VIRTIO_GPU_RESP_ERR_INVALID_SCANOUT_ID; - return; - } - res = virtio_gpu_find_resource(g, ss.resource_id); if (!res) { qemu_log_mask(LOG_GUEST_ERROR, "%s: illegal resource specified %d\n",