Re: Re: [PATCH] octeontx2-af: Fix use of uninitialized pointer bmap

From: dinghao . liu
Date: Sat Jul 25 2020 - 01:55:43 EST


> From: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
> Date: Fri, 24 Jul 2020 16:06:57 +0800
>
> > If req->ctype does not match any of NIX_AQ_CTYPE_CQ,
> > NIX_AQ_CTYPE_SQ or NIX_AQ_CTYPE_RQ, pointer bmap will remain
> > uninitialized and be accessed in test_bit(), which can lead
> > to kernal crash.
>
> This can never happen.
>
> > Fix this by returning an error code if this case is triggered.
> >
> > Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
>
> I strongly dislike changes like this.
>
> Most callers of nix_lf_hwctx_disable() inside of rvu_nix.c set
> req->ctype to one of the handled values.
>
> The only other case, rvu_mbox_handler_nix_hwctx_disable(), is a
> completely unused function and should be removed.
>
> There is no functional problem in this code at all.
>
> It is not possible show a code path where the stated problem can
> actually occur.

It's clear to me now. Thanks.

Regards,
Dinghao