RE: [PATCH rdma-next 5/6] RDMA/mana_ib: boundary check before installing cq callbacks

Konstantin Taranov
2024-04-24T08:58:15Z

> > Add a boundary check inside mana_ib_install_cq_cb to prevent index
> > overflow.
>
> How is this condition possible that we are getting an out of bound queue id
> from SOC?
>

Yes, it should not happen as the HW says the upper limit on CQ_ID,
but I think it is safer to have it to dodge bugs/faulty HW.
Better safe than sorry.
You can see the same check all over the mana.ko module.

> >
> > Fixes: 2a31c5a7e0d8 ("RDMA/mana_ib: Introduce mana_ib_install_cq_cb
> > helper function")
> > Signed-off-by: Konstantin Taranov <kotaranov@microsoft.com>
> > ---
> > drivers/infiniband/hw/mana/cq.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/infiniband/hw/mana/cq.c
> > b/drivers/infiniband/hw/mana/cq.c index 6c3bb8c..8323085 100644
> > --- a/drivers/infiniband/hw/mana/cq.c
> > +++ b/drivers/infiniband/hw/mana/cq.c
> > @@ -70,6 +70,8 @@ int mana_ib_install_cq_cb(struct mana_ib_dev
> *mdev,
> > struct mana_ib_cq *cq)
> > struct gdma_context *gc = mdev_to_gc(mdev);
> > struct gdma_queue *gdma_cq;
> >
> > + if (cq->queue.id >= gc->max_num_cqs)
> > + return -EINVAL;
> > /* Create CQ table entry */
> > WARN_ON(gc->cq_table[cq->queue.id]);
> > gdma_cq = kzalloc(sizeof(*gdma_cq), GFP_KERNEL);
> > --
> > 2.43.0