phy: qcom-qmp-usb: Fix an NULL vs IS_ERR() bug

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@gmail.com>
Fixes: a5d6b1ac56cb ("phy: qcom-qmp-usb: fix memleak on probe deferral")
CC: Johan Hovold <johan@kernel.org>
CC: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250414125050.2118619-1-chenyuan0y@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-usb.c b/drivers/phy/qualcomm/phy-qcom-qmp-usb.c
index 78772157045752d618cfe01c9a9fedb1f5adc766..ed646a7e705ba3259708775ed5fedbbbada13735 100644 (file)
--- a/drivers/phy/qualcomm/phy-qcom-qmp-usb.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-usb.c
@@ -2106,12 +2106,16 @@ static void __iomem *qmp_usb_iomap(struct device *dev, struct device_node *np,
                                        int index, bool exclusive)
 {
        struct resource res;
+       void __iomem *mem;
 
        if (!exclusive) {
                if (of_address_to_resource(np, index, &res))
                        return IOMEM_ERR_PTR(-EINVAL);
 
-               return devm_ioremap(dev, res.start, resource_size(&res));
+               mem = devm_ioremap(dev, res.start, resource_size(&res));
+               if (!mem)
+                       return IOMEM_ERR_PTR(-ENOMEM);
+               return mem;
        }
 
        return devm_of_iomap(dev, np, index, NULL);