[PATCH] can: mcp251xfd: reject devices without match data

[Jiale Yao]

A device bound through driver_override need not match an entry in the
driver tables. In that case spi_get_device_match_data() returns NULL,
but mcp251xfd_probe() dereferences the result while copying the device
type data.

Reject devices without match data before continuing probe.

Fixes: 9cdae370c4ec ("can: mcp251xfd: simplify with spi_get_device_match_data()")
Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
---
 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
index f441f2265299..8759bc05bd8f 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
@@ -2213,6 +2213,7 @@ MODULE_DEVICE_TABLE(spi, mcp251xfd_id_table);
 
 static int mcp251xfd_probe(struct spi_device *spi)
 {
+	const struct mcp251xfd_devtype_data *devtype_data;
 	struct net_device *ndev;
 	struct mcp251xfd_priv *priv;
 	struct gpio_desc *rx_int;
@@ -2222,6 +2223,10 @@ static int mcp251xfd_probe(struct spi_device *spi)
 	u32 freq = 0;
 	int err;
 
+	devtype_data = spi_get_device_match_data(spi);
+	if (!devtype_data)
+		return -ENODATA;
+
 	if (!spi->irq)
 		return dev_err_probe(&spi->dev, -ENXIO,
 				     "No IRQ specified (maybe node \"interrupts-extended\" in DT missing)!\n");
@@ -2307,7 +2312,7 @@ static int mcp251xfd_probe(struct spi_device *spi)
 	priv->reg_vdd = reg_vdd;
 	priv->reg_xceiver = reg_xceiver;
 	priv->xstbyen = device_property_present(&spi->dev, "microchip,xstbyen");
-	priv->devtype_data = *(struct mcp251xfd_devtype_data *)spi_get_device_match_data(spi);
+	priv->devtype_data = *devtype_data;
 
 	/* Errata Reference:
 	 * mcp2517fd: DS80000792C 5., mcp2518fd: DS80000789E 4.,
-- 
2.34.1