Commit ce7536bc authored by Stefano Garzarella's avatar Stefano Garzarella Committed by Jakub Kicinski
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vsock/virtio: update credit only if socket is not closed 



If the socket is closed or is being released, some resources used by
virtio_transport_space_update() such as 'vsk->trans' may be released.

To avoid a use after free bug we should only update the available credit
when we are sure the socket is still open and we have the lock held.

Fixes: 06a8fc78 ("VSOCK: Introduce virtio_vsock_common.ko")
Signed-off-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Acked-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20210208144454.84438-1-sgarzare@redhat.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent af8085f3

net/vmw_vsock/virtio_transport_common.c

+2 −2
Original line number Diff line number Diff line
@@ -1130,8 +1130,6 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, 


	vsk = vsock_sk(sk);



	space_available = virtio_transport_space_update(sk, pkt);



	lock_sock(sk);



	/* Check if sk has been closed before lock_sock */
@@ -1142,6 +1140,8 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, 
		goto free_pkt;

	}



	space_available = virtio_transport_space_update(sk, pkt);



	/* Update CID in case it has changed after a transport reset event */

	vsk->local_addr.svm_cid = dst.svm_cid;