[PATCH 4.4 31/84] PCI: xilinx: Check for __get_free_pages() failure

From: Greg Kroah-Hartman
Date: Thu Jun 20 2019 - 13:59:28 EST


[ Upstream commit 699ca30162686bf305cdf94861be02eb0cf9bda2 ]

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

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Reviewed-by: Steven Price <steven.price@xxxxxxx>
Reviewed-by: Mukesh Ojha <mojha@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pci/host/pcie-xilinx.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c
index 4cfa46360d12..6a2499f4d610 100644
--- a/drivers/pci/host/pcie-xilinx.c
+++ b/drivers/pci/host/pcie-xilinx.c
@@ -349,14 +349,19 @@ 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 */
@@ -555,6 +560,7 @@ 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);
@@ -582,7 +588,9 @@ static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port)
return PTR_ERR(port->irq_domain);
}

- xilinx_pcie_enable_msi(port);
+ ret = xilinx_pcie_enable_msi(port);
+ if (ret)
+ return ret;
}

return 0;
--
2.20.1