PCI: xilinx: Check for __get_free_pages() failure

[ Upstream commit 699ca30162686bf305cdf94861be02eb0cf9bda2 ]

If __get_free_pages() fails, return -ENOMEM to avoid a NULL pointer
dereference.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c
index 61332f4..c3964fc 100644 (file)
--- a/drivers/pci/host/pcie-xilinx.c
+++ b/drivers/pci/host/pcie-xilinx.c
@@ -337,14 +337,19 @@ static const struct irq_domain_ops msi_domain_ops = {
  * xilinx_pcie_enable_msi - Enable MSI support
  * @port: PCIe port information
  */
-static void xilinx_pcie_enable_msi(struct xilinx_pcie_port *port)
+static int xilinx_pcie_enable_msi(struct xilinx_pcie_port *port)
 {
        phys_addr_t msg_addr;
 
        port->msi_pages = __get_free_pages(GFP_KERNEL, 0);
+       if (!port->msi_pages)
+               return -ENOMEM;
+
        msg_addr = virt_to_phys((void *)port->msi_pages);
        pcie_write(port, 0x0, XILINX_PCIE_REG_MSIBASE1);
        pcie_write(port, msg_addr, XILINX_PCIE_REG_MSIBASE2);
+
+       return 0;
 }
 
 /* INTx Functions */
@@ -516,6 +521,7 @@ static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port)
        struct device *dev = port->dev;
        struct device_node *node = dev->of_node;
        struct device_node *pcie_intc_node;
+       int ret;
 
        /* Setup INTx */
        pcie_intc_node = of_get_next_child(node, NULL);
@@ -544,7 +550,9 @@ static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port)
                        return -ENODEV;
                }
 
-               xilinx_pcie_enable_msi(port);
+               ret = xilinx_pcie_enable_msi(port);
+               if (ret)
+                       return ret;
        }
 
        return 0;