Re: [PATCH net-next v8 5/7] net: phy: nxp-c45-tja11xx: add MACsec support

[Radu Pirea (OSS)]

On 04.11.2023 13:35, Simon Horman wrote:
> On Mon, Oct 23, 2023 at 12:43:25PM +0300, Radu Pirea (NXP OSS) wrote:
> > +void nxp_c45_handle_macsec_interrupt(struct phy_device *phydev,
> > +				     irqreturn_t *ret)
> > +{
> > +	struct nxp_c45_phy *priv = phydev->priv;
> > +	struct nxp_c45_secy *pos, *tmp;
> > +	struct nxp_c45_sa *sa;
> > +	u8 encoding_sa;
> > +	int secy_id;
> > +	u32 reg = 0;
> > +
> > +	if (!priv->macsec)
> > +		return;
> > +
> > +	do {
> > +		nxp_c45_macsec_read(phydev, MACSEC_EVR, &reg);
> > +		if (!reg)
> > +			return;
> > +
> > +		secy_id = MACSEC_REG_SIZE - ffs(reg);
> > +		list_for_each_entry_safe(pos, tmp, &priv->macsec->secy_list,
> > +					 list)
> > +			if (pos->secy_id == secy_id)
> > +				break;
> > +
> > +		encoding_sa = pos->secy->tx_sc.encoding_sa;
>
> Hi Radu,
>
> I'm unsure if this can happen, but my understanding is that if
> priv->macsec->secy_list is empty then pos will be uninitialised here.
>
> Flagged by Coccinelle.

True, this this should never happen. No MACsec interrupt should be 
triggered if that list is empty. The IRQ for PN wrap is enabled only 
when a secy is added and disabled when the secy is removed. I added a 
safety check anyway.

--
Radu P.