| Message ID | 1516284037-81537-1-git-send-email-weiyongjun1@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Thu, Jan 18, 2018 at 02:00:37PM +0000, Wei Yongjun wrote: > platform_get_resource_byname() 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_byname(pdev, t, n); > + if (!res) > + return -EINVAL; > ... when != res == NULL > e = devm_ioremap(e1, res->start, e2); This pattern of: platform_get_resource_byname devm_ioremap is extremely common and could perhaps be factored out. There are already a few private versions, e.g., request_and_map(), msm_ioremap(), ssi_get_iomem(). request_and_map() also includes devm_request_mem_region(), which probably *should* be included but usually seems to be omitted. > Fixes: 608793e27b33 ("PCI: dwc: dra7xx: Add EP mode support") > Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> > --- > drivers/pci/dwc/pci-dra7xx.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c > index 8bf7c27..aafded8 100644 > --- a/drivers/pci/dwc/pci-dra7xx.c > +++ b/drivers/pci/dwc/pci-dra7xx.c > @@ -409,11 +409,15 @@ static int __init dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx, > ep->ops = &pcie_ep_ops; > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics"); > + if (!res) > + return -EINVAL; > pci->dbi_base = devm_ioremap(dev, res->start, resource_size(res)); > if (!pci->dbi_base) > return -ENOMEM; > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics2"); > + if (!res) > + return -EINVAL; > pci->dbi_base2 = devm_ioremap(dev, res->start, resource_size(res)); > if (!pci->dbi_base2) > return -ENOMEM; > @@ -462,6 +466,8 @@ static int __init dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx, > return ret; > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics"); > + if (!res) > + return -EINVAL; > pci->dbi_base = devm_ioremap(dev, res->start, resource_size(res)); > if (!pci->dbi_base) > return -ENOMEM; >
On Thu, Jan 18, 2018 at 02:00:37PM +0000, Wei Yongjun wrote: > platform_get_resource_byname() 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_byname(pdev, t, n); > + if (!res) > + return -EINVAL; > ... when != res == NULL > e = devm_ioremap(e1, res->start, e2); Well, then it should be replaced with devm_ioremap_resource() which already checks for NULL and the right resource type (IORESOURCE_MEM). ladis > Fixes: 608793e27b33 ("PCI: dwc: dra7xx: Add EP mode support") > Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> > --- > drivers/pci/dwc/pci-dra7xx.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c > index 8bf7c27..aafded8 100644 > --- a/drivers/pci/dwc/pci-dra7xx.c > +++ b/drivers/pci/dwc/pci-dra7xx.c > @@ -409,11 +409,15 @@ static int __init dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx, > ep->ops = &pcie_ep_ops; > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics"); > + if (!res) > + return -EINVAL; > pci->dbi_base = devm_ioremap(dev, res->start, resource_size(res)); > if (!pci->dbi_base) > return -ENOMEM; > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics2"); > + if (!res) > + return -EINVAL; > pci->dbi_base2 = devm_ioremap(dev, res->start, resource_size(res)); > if (!pci->dbi_base2) > return -ENOMEM; > @@ -462,6 +466,8 @@ static int __init dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx, > return ret; > > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics"); > + if (!res) > + return -EINVAL; > pci->dbi_base = devm_ioremap(dev, res->start, resource_size(res)); > if (!pci->dbi_base) > return -ENOMEM; > > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c index 8bf7c27..aafded8 100644 --- a/drivers/pci/dwc/pci-dra7xx.c +++ b/drivers/pci/dwc/pci-dra7xx.c @@ -409,11 +409,15 @@ static int __init dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx, ep->ops = &pcie_ep_ops; res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics"); + if (!res) + return -EINVAL; pci->dbi_base = devm_ioremap(dev, res->start, resource_size(res)); if (!pci->dbi_base) return -ENOMEM; res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ep_dbics2"); + if (!res) + return -EINVAL; pci->dbi_base2 = devm_ioremap(dev, res->start, resource_size(res)); if (!pci->dbi_base2) return -ENOMEM; @@ -462,6 +466,8 @@ static int __init dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx, return ret; res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics"); + if (!res) + return -EINVAL; pci->dbi_base = devm_ioremap(dev, res->start, resource_size(res)); if (!pci->dbi_base) return -ENOMEM;
platform_get_resource_byname() 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_byname(pdev, t, n); + if (!res) + return -EINVAL; ... when != res == NULL e = devm_ioremap(e1, res->start, e2); Fixes: 608793e27b33 ("PCI: dwc: dra7xx: Add EP mode support") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> --- drivers/pci/dwc/pci-dra7xx.c | 6 ++++++ 1 file changed, 6 insertions(+)