[57/64] vhost-user-gpu: fix memory leak in vg_resource_attach_backing (CVE-2021-3544)

Commit Message

Michael Roth Oct. 19, 2021, 2:09 p.m. UTC

From: Li Qiang <[e-mail]>

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

Fixes: CVE-2021-3544
Reported-by: Li Qiang <[e-mail]>
virtio-gpu fix: 204f01b309 ("virtio-gpu: fix memory leak
in resource attach backing")

Signed-off-by: Li Qiang <[e-mail]>
Reviewed-by: Marc-André Lureau <[e-mail]>
Message-Id: <[e-mail]>
Signed-off-by: Gerd Hoffmann <[e-mail]>
(cherry picked from commit b9f79858a614d95f5de875d0ca31096eaab72c3b)
Signed-off-by: Michael Roth <[e-mail]>
---
 contrib/vhost-user-gpu/vhost-user-gpu.c | 5 +++++
 1 file changed, 5 insertions(+)

Patch

diff --git a/contrib/vhost-user-gpu/vhost-user-gpu.c b/contrib/vhost-user-gpu/vhost-user-gpu.c
index b5e153d0d6..0437e52b64 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;