Re: [PATCH V1 12/15] spmi-pmic-arb: fix a possible null pointer dereference

[kgunda]

On 2017-05-31 22:59, Stephen Boyd wrote:

On 05/30, Kiran Gunda wrote:

diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c

index 2afe359..412481d 100644
--- a/drivers/spmi/spmi-pmic-arb.c
+++ b/drivers/spmi/spmi-pmic-arb.c

@@ -1003,6 +1003,12 @@ static int spmi_pmic_arb_probe(struct platform_device *pdev)

        pa->spmic = ctrl;

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "core");
+       if (!res) {
+               dev_err(&pdev->dev, "core resource not specified\n");
+               err = -EINVAL;
+               goto err_put_ctrl;
+       }
+
        pa->core_size = resource_size(res);
        if (pa->core_size <= 0x800) {

dev_err(&pdev->dev, "core_size is smaller than 0x800. Failing Probe\n");

I would prefer this patch instead, so that we can piggyback on
the error checking of the devm_ioremap_resource() code. Also, add
a Fixes: tag please so we can backport it as needed.

Sure. We will modify as per your suggestion in the next patch.

diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c

index 5ec3a595dc7d..0cedbda60707 100644
--- a/drivers/spmi/spmi-pmic-arb.c
+++ b/drivers/spmi/spmi-pmic-arb.c
@@ -878,12 +878,12 @@ static int spmi_pmic_arb_probe(struct
platform_device *pdev)
        pa->spmic = ctrl;

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "core");
-       pa->core_size = resource_size(res);
        core = devm_ioremap_resource(&ctrl->dev, res);
        if (IS_ERR(core)) {
                err = PTR_ERR(core);
                goto err_put_ctrl;
        }
+       pa->core_size = resource_size(res);

        hw_ver = readl_relaxed(core + PMIC_ARB_VERSION);
        is_v1  = (hw_ver < PMIC_ARB_VERSION_V2_MIN);