# Re: \[PATCH net V2\] vhost-vsock: fix use after free

- From: Stefan Hajnoczi \<stefanha@redhat.com\>
- Date: 2018-09-27 15:33:33 
- List: netdev
- Page: https://ratatoskr.run/netdev/2018/09/5393306
- Thread: https://ratatoskr.run/kvm/2018/09/5393106/t.md

```text
On Thu, Sep 27, 2018 at 08:22:04PM +0800, Jason Wang wrote:
> The access of vsock is not protected by vhost_vsock_lock. This may
> lead to use after free since vhost_vsock_dev_release() may free the
> pointer at the same time.
> 
> Fix this by holding the lock during the access.
> 
> Reported-by: <redacted>
> Fixes: 16320f363ae1 ("vhost-vsock: add pkt cancel capability")
> Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko")
> Cc: Stefan Hajnoczi <stefanha@redhat.com>
> Signed-off-by: Jason Wang <redacted>
> ---
> - V2: fix typos
> - The patch is needed for -stable.
> ---
>  drivers/vhost/vsock.c | 26 +++++++++++++++++++-------
>  1 file changed, 19 insertions(+), 7 deletions(-)

Thank you, Jason!

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
```