[PATCH for-5.10] spi: pxa2xx: Fix use-after-free on unbind

[Lukas Wunner <lukas@xxxxxxxxx>]

pxa2xx_spi_remove() accesses the driver's private data after calling
spi_unregister_controller() even though that function releases the last
reference on the spi_controller and thereby frees the private data.

Fix by switching over to the new devm_spi_alloc_master/slave() helper
which keeps the private data accessible until the driver has unbound.

Fixes: 32e5b57232c0 ("spi: pxa2xx: Fix controller unregister order")
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v2.6.17+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation
Cc: <stable@xxxxxxxxxxxxxxx> # v2.6.17+: 32e5b57232c0: spi: pxa2xx: Fix controller unregister order
Cc: <stable@xxxxxxxxxxxxxxx> # v2.6.17+
---
 drivers/spi/spi-pxa2xx.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 814268405ab0..d6b534d38e5d 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1686,9 +1686,9 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
 	}
 
 	if (platform_info->is_slave)
-		controller = spi_alloc_slave(dev, sizeof(struct driver_data));
+		controller = devm_spi_alloc_slave(dev, sizeof(*drv_data));
 	else
-		controller = spi_alloc_master(dev, sizeof(struct driver_data));
+		controller = devm_spi_alloc_master(dev, sizeof(*drv_data));
 
 	if (!controller) {
 		dev_err(&pdev->dev, "cannot alloc spi_controller\n");
@@ -1911,7 +1911,6 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
 	free_irq(ssp->irq, drv_data);
 
 out_error_controller_alloc:
-	spi_controller_put(controller);
 	pxa_ssp_free(ssp);
 	return status;
 }
-- 
2.28.0