spi: bcm2835: Fix use-after-free on unbind

[ Upstream commit e1483ac030 ]

bcm2835_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() helper which
keeps the private data accessible until the driver has unbound.

Fixes: f8043872e7 ("spi: add driver for BCM2835")
Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
Reported-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v3.10+: 5e844cc37a: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v3.10+
Cc: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/ad66e0a0ad96feb848814842ecf5b6a4539ef35c.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Lukas Wunner
2020-12-06 13:46:02 +01:00
committed by Greg Kroah-Hartman
parent 5aea0d9667
commit 2be1837b17

View File

@@ -737,7 +737,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
struct resource *res;
int err;
master = spi_alloc_master(&pdev->dev, sizeof(*bs));
master = devm_spi_alloc_master(&pdev->dev, sizeof(*bs));
if (!master) {
dev_err(&pdev->dev, "spi_alloc_master() failed\n");
return -ENOMEM;
@@ -759,23 +759,20 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
bs->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(bs->regs)) {
err = PTR_ERR(bs->regs);
goto out_master_put;
}
if (IS_ERR(bs->regs))
return PTR_ERR(bs->regs);
bs->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(bs->clk)) {
err = PTR_ERR(bs->clk);
dev_err(&pdev->dev, "could not get clk: %d\n", err);
goto out_master_put;
return err;
}
bs->irq = platform_get_irq(pdev, 0);
if (bs->irq <= 0) {
dev_err(&pdev->dev, "could not get IRQ: %d\n", bs->irq);
err = bs->irq ? bs->irq : -ENODEV;
goto out_master_put;
return bs->irq ? bs->irq : -ENODEV;
}
clk_prepare_enable(bs->clk);
@@ -803,8 +800,6 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
out_clk_disable:
clk_disable_unprepare(bs->clk);
out_master_put:
spi_master_put(master);
return err;
}