powerpc/powernv: Add sanity checks to pnv_pci_get_{gpu|npu}_dev
The pnv_pci_get_{gpu|npu}_dev functions are used to find associations
between nvlink PCIe devices and standard PCIe devices. However they
lacked basic sanity checking which results in NULL pointer
dereferencing if they are incorrect called can be harder to spot than
an explicit WARN_ON.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 1c383f3..050bd5d 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -37,6 +37,12 @@
struct device_node *dn;
struct pci_dev *gpdev;
+ if (WARN_ON(!npdev))
+ return NULL;
+
+ if (WARN_ON(!npdev->dev.of_node))
+ return NULL;
+
/* Get assoicated PCI device */
dn = of_parse_phandle(npdev->dev.of_node, "ibm,gpu", 0);
if (!dn)
@@ -55,6 +61,12 @@
struct device_node *dn;
struct pci_dev *npdev;
+ if (WARN_ON(!gpdev))
+ return NULL;
+
+ if (WARN_ON(!gpdev->dev.of_node))
+ return NULL;
+
/* Get assoicated PCI device */
dn = of_parse_phandle(gpdev->dev.of_node, "ibm,npu", index);
if (!dn)