Re: [PATCH v2] phy: qcom-qmp-usb: Fix an NULL vs IS_ERR() bug

[Dmitry Baryshkov]

On Mon, Apr 14, 2025 at 07:50:50AM -0500, Chenyuan Yang wrote:
> The qmp_usb_iomap() helper function currently returns the raw result of
> devm_ioremap() for non-exclusive mappings. Since devm_ioremap() may return
> a NULL pointer and the caller only checks error pointers with IS_ERR(),
> NULL could bypass the check and lead to an invalid dereference.
> 
> Fix the issue by checking if devm_ioremap() returns NULL. When it does,
> qmp_usb_iomap() now returns an error pointer via IOMEM_ERR_PTR(-ENOMEM),
> ensuring safe and consistent error handling.
> 
> Signed-off-by: Chenyuan Yang <chenyuan0y@xxxxxxxxx>
> Fixes: a5d6b1ac56cb ("phy: qcom-qmp-usb: fix memleak on probe deferral")
> CC: Johan Hovold <johan@xxxxxxxxxx>
> CC: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> ---
>  drivers/phy/qualcomm/phy-qcom-qmp-usb.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>

-- 
With best wishes
Dmitry