spi: atmel-quadspi: Fix use-after-free on unbind

commit c7b884561cb5b641f3dbba950094110794119a6d upstream.

atmel_qspi_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: 2d30ac5ed6 ("mtd: spi-nor: atmel-quadspi: Use spi-mem interface for atmel-quadspi driver")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v5.0+: 5e844cc37a: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v5.0+
Cc: Piotr Bugalski <bugalski.piotr@gmail.com>
Link: https://lore.kernel.org/r/4b05c65cf6f1ea3251484fe9a00b4c65478a1ae3.1607286887.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 2020-12-07 09:17:17 +01:00 committed by Greg Kroah-Hartman
parent 6726316404
commit 9be450fa3f

View File

@ -535,7 +535,7 @@ static int atmel_qspi_probe(struct platform_device *pdev)
struct resource *res;
int irq, err = 0;
ctrl = spi_alloc_master(&pdev->dev, sizeof(*aq));
ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(*aq));
if (!ctrl)
return -ENOMEM;
@ -557,8 +557,7 @@ static int atmel_qspi_probe(struct platform_device *pdev)
aq->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(aq->regs)) {
dev_err(&pdev->dev, "missing registers\n");
err = PTR_ERR(aq->regs);
goto exit;
return PTR_ERR(aq->regs);
}
/* Map the AHB memory */
@ -566,8 +565,7 @@ static int atmel_qspi_probe(struct platform_device *pdev)
aq->mem = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(aq->mem)) {
dev_err(&pdev->dev, "missing AHB memory\n");
err = PTR_ERR(aq->mem);
goto exit;
return PTR_ERR(aq->mem);
}
aq->mmap_size = resource_size(res);
@ -579,15 +577,14 @@ static int atmel_qspi_probe(struct platform_device *pdev)
if (IS_ERR(aq->pclk)) {
dev_err(&pdev->dev, "missing peripheral clock\n");
err = PTR_ERR(aq->pclk);
goto exit;
return PTR_ERR(aq->pclk);
}
/* Enable the peripheral clock */
err = clk_prepare_enable(aq->pclk);
if (err) {
dev_err(&pdev->dev, "failed to enable the peripheral clock\n");
goto exit;
return err;
}
aq->caps = of_device_get_match_data(&pdev->dev);
@ -638,8 +635,6 @@ static int atmel_qspi_probe(struct platform_device *pdev)
clk_disable_unprepare(aq->qspick);
disable_pclk:
clk_disable_unprepare(aq->pclk);
exit:
spi_controller_put(ctrl);
return err;
}