From: Li Qiang <liq3ea@163.com>
Date: Sun, 16 May 2021 03:03:58 +0000 (-0700)
Subject: vhost-user-gpu: fix memory leak in vg_resource_attach_backing (CVE-2021-3544)
X-Git-Tag: v6.0.1~12
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6ae68dfd10e53466e341f8330e0c8f9f10bd5d54;p=thirdparty%2Fqemu.git

vhost-user-gpu: fix memory leak in vg_resource_attach_backing (CVE-2021-3544)

Check whether the 'res' has already been attach_backing to avoid
memory leak.

Fixes: CVE-2021-3544
Reported-by: Li Qiang <liq3ea@163.com>
virtio-gpu fix: 204f01b309 ("virtio-gpu: fix memory leak
in resource attach backing")

Signed-off-by: Li Qiang <liq3ea@163.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210516030403.107723-4-liq3ea@163.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit b9f79858a614d95f5de875d0ca31096eaab72c3b)
Signed-off-by: Michael Roth <michael.roth@amd.com>
---

diff --git a/contrib/vhost-user-gpu/vhost-user-gpu.c b/contrib/vhost-user-gpu/vhost-user-gpu.c
index b5e153d0d64..0437e52b646 100644
--- a/contrib/vhost-user-gpu/vhost-user-gpu.c
+++ b/contrib/vhost-user-gpu/vhost-user-gpu.c
@@ -489,6 +489,11 @@ vg_resource_attach_backing(VuGpu *g,
         return;
     }
 
+    if (res->iov) {
+        cmd->error = VIRTIO_GPU_RESP_ERR_UNSPEC;
+        return;
+    }
+
     ret = vg_create_mapping_iov(g, &ab, cmd, &res->iov);
     if (ret != 0) {
         cmd->error = VIRTIO_GPU_RESP_ERR_UNSPEC;