spi: mchp-pci1xxx: Fix a possible null pointer dereference in pci1xxx_spi_probe

[ Upstream commit 1f886a7bfb3faf4c1021e73f045538008ce7634e ]

In function pci1xxxx_spi_probe, there is a potential null pointer that
may be caused by a failed memory allocation by the function devm_kzalloc.
Hence, a null pointer check needs to be added to prevent null pointer
dereferencing later in the code.

To fix this issue, spi_bus->spi_int[iter] should be checked. The memory
allocated by devm_kzalloc will be automatically released, so just directly
return -ENOMEM without worrying about memory leaks.

Fixes: 1cc0cbea7167 ("spi: microchip: pci1xxxx: Add driver for SPI controller of PCI1XXXX PCIe switch")
Signed-off-by: Huai-Yuan Liu <qq810974084@gmail.com>
Link: https://msgid.link/r/20240403014221.969801-1-qq810974084@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/spi/spi-pci1xxxx.c b/drivers/spi/spi-pci1xxxx.c
index 5b2d3e4e21b7ab470be5c24fc145cdcd22521b47..5a42266820522d53861fdf1fa073ff1d4ae82131 100644 (file)
--- a/drivers/spi/spi-pci1xxxx.c
+++ b/drivers/spi/spi-pci1xxxx.c
@@ -275,6 +275,8 @@ static int pci1xxxx_spi_probe(struct pci_dev *pdev, const struct pci_device_id *
                spi_bus->spi_int[iter] = devm_kzalloc(&pdev->dev,
                                                      sizeof(struct pci1xxxx_spi_internal),
                                                      GFP_KERNEL);
+               if (!spi_bus->spi_int[iter])
+                       return -ENOMEM;
                spi_sub_ptr = spi_bus->spi_int[iter];
                spi_sub_ptr->spi_host = devm_spi_alloc_host(dev, sizeof(struct spi_controller));
                if (!spi_sub_ptr->spi_host)