On Tue, Nov 07, 2017 at 10:27:10AM +0800, Longpeng (Mike) wrote:
>
>
> On 2017/11/7 1:00, Eric Blake wrote:
>
> > On 11/06/2017 12:21 AM, Longpeng(Mike) wrote:
> >> Test-crypto-hash calls qcrypto_hash_bytesv/digest/base64 with
> >> errp=NULL, this will cause a NULL poniter deference if afalg_driver
> >
> > s/poniter deference/pointer dereference/
> >
>
> OK.
>
> >> doesn't support requested algos:
> >> ret = qcrypto_hash_afalg_driver.hash_bytesv(alg, iov, niov,
> >> result, resultlen,
> >> errp);
> >> if (ret == 0) {
> >> return ret;
> >> }
> >>
> >> error_free(*errp); // <--- here
> >>
> >> So we must check 'errp & *errp' before dereference.
> >
> > No, if we are going to blindly ignore the error from the hash_bytesv()
> > call, then we should pass NULL rather than errp.
> >
>
> The 'errp' in this palce is convenient for debug, it can tell us the reason
> for
> failure without stepping into afalg_driver's hash_bytesv().
It doesn't do anything useful for debug, because we are just immediately
throwing away the error without printing it anywhere. Just pass NULL into
the hash_bytesv call above.
Regards,
Daniel
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