Re: [PATCH] phy: qcom-qmp-combo: fix NULL-deref on runtime resume

From: Andrew Halaney
Date: Wed Oct 26 2022 - 15:15:19 EST


On Wed, Oct 26, 2022 at 06:21:16PM +0200, Johan Hovold wrote:
> Commit fc64623637da ("phy: qcom-qmp-combo,usb: add support for separate
> PCS_USB region") started treating the PCS_USB registers as potentially
> separate from the PCS registers but used the wrong base when no PCS_USB
> offset has been provided.
>
> Fix the PCS_USB base used at runtime resume to prevent dereferencing a
> NULL pointer on platforms that do not provide a PCS_USB offset (e.g.
> SC7180).
>
> Fixes: fc64623637da ("phy: qcom-qmp-combo,usb: add support for separate PCS_USB region")
> Cc: stable@xxxxxxxxxxxxxxx # 5.20
> Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>

Reviewed-by: Andrew Halaney <ahalaney@xxxxxxxxxx>

For what it is worth, I double checked and phy-qcom-qmp-usb.c has this
done properly already.

Thanks,
Andrew

> ---
> drivers/phy/qualcomm/phy-qcom-qmp-combo.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> index f6328434c61e..ad6a0fd7ba8e 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> @@ -2144,7 +2144,7 @@ static void qmp_combo_enable_autonomous_mode(struct qmp_phy *qphy)
> static void qmp_combo_disable_autonomous_mode(struct qmp_phy *qphy)
> {
> const struct qmp_phy_cfg *cfg = qphy->cfg;
> - void __iomem *pcs_usb = qphy->pcs_usb ?: qphy->pcs_usb;
> + void __iomem *pcs_usb = qphy->pcs_usb ?: qphy->pcs;
> void __iomem *pcs_misc = qphy->pcs_misc;
>
> /* Disable i/o clamp_n on resume for normal mode */
> --
> 2.37.3
>