Re: [PATCH] vhost/vsock: always initialize seqpacket_allow

[Stefano Garzarella]

On Wed, May 15, 2024 at 11:05:43AM GMT, Michael S. Tsirkin wrote:
> There are two issues around seqpacket_allow:
> 1. seqpacket_allow is not initialized when socket is
>   created. Thus if features are never set, it will be
>   read uninitialized.
> 2. if VIRTIO_VSOCK_F_SEQPACKET is set and then cleared,
>   then seqpacket_allow will not be cleared appropriately
>   (existing apps I know about don't usually do this but
>    it's legal and there's no way to be sure no one relies
>    on this).
>
> To fix:
> 	- initialize seqpacket_allow after allocation
> 	- set it unconditionally in set_features
>
> Reported-by: syzbot+6c21aeb59d0e82eb2782@xxxxxxxxxxxxxxxxxxxxxxxxx
> Reported-by: Jeongjun Park <aha310510@xxxxxxxxx>
> Fixes: ced7b713711f ("vhost/vsock: support SEQPACKET for transport").
> Cc: Arseny Krasnov <arseny.krasnov@xxxxxxxxxxxxx>
> Cc: David S. Miller <davem@xxxxxxxxxxxxx>
> Cc: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> Acked-by: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxxxxx>
> Tested-by: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxxxxx>
>
> ---
>
>
> Reposting now it's been tested.
>
> drivers/vhost/vsock.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)

Thanks for fixing this issue!

Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>