Hi, On 27/04/20 4:40 pm, Wei Yongjun wrote: > platform_get_resource() may fail and return NULL, so we should > better check it's return value to avoid a NULL pointer dereference > a bit later in the code. > > This is detected by Coccinelle semantic patch. > > @@ > expression pdev, res, n, t, e, e1, e2; > @@ > > res = \(platform_get_resource\|platform_get_resource_byname\)(pdev, t, n); > + if (!res) > + return -EINVAL; > ... when != res == NULL > e = devm_ioremap(e1, res->start, e2); > > Signed-off-by: Wei Yongjun <weiyongjun1@xxxxxxxxxx> > --- > drivers/pci/controller/dwc/pci-dra7xx.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c > index 3b0e58f2de58..7a3d12f7e7d9 100644 > --- a/drivers/pci/controller/dwc/pci-dra7xx.c > +++ b/drivers/pci/controller/dwc/pci-dra7xx.c > @@ -878,6 +878,9 @@ static int __init dra7xx_pcie_probe(struct platform_device *pdev) > } > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf"); > + if (!res) > + return -EINVAL; > + > base = devm_ioremap(dev, res->start, resource_size(res)); I don't see why this should be devm_ioremap(). It should also have been devm_ioremap_resource() which does the NULL check. Alternately, how about using devm_platform_ioremap_resource_byname()? > if (!base) > return -ENOMEM; > > > > >
