vhost-user-gpu: fix resource leak in 'vg_resource_create_2d' (CVE-2021-3544)

Call 'vugbm_buffer_destroy' in error path to avoid resource leak.

Fixes: CVE-2021-3544
Reported-by: default avatarLi Qiang <liq3ea@163.com>
Reviewed-by: default avatarPrasad J Pandit <pjp@fedoraproject.org>
Signed-off-by: default avatarLi Qiang <liq3ea@163.com>
Reviewed-by: Marc-André Lureau's avatarMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210516030403.107723-3-liq3ea@163.com>
Signed-off-by: Gerd Hoffmann's avatarGerd Hoffmann <kraxel@redhat.com>

Upstream-Status: Backport
[vhost-user-gpu does not exist in 4.2.0]
CVE: CVE-2021-3544
Signed-off-by: Armin Kuster <akuster@mvista.com>

Index: qemu-4.2.0/contrib/vhost-user-gpu/main.c
===================================================================
--- qemu-4.2.0.orig/contrib/vhost-user-gpu/main.c
+++ qemu-4.2.0/contrib/vhost-user-gpu/main.c
@@ -328,6 +328,7 @@ vg_resource_create_2d(VuGpu *g,
         g_critical("%s: resource creation failed %d %d %d",
                    __func__, c2d.resource_id, c2d.width, c2d.height);
         g_free(res);
+        vugbm_buffer_destroy(&res->buffer);
         cmd->error = VIRTIO_GPU_RESP_ERR_OUT_OF_MEMORY;
         return;
     }