From 236924ee531d6251c8d10e9177b7742a60534ed5 Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Mon, 7 Dec 2020 09:17:15 +0100 Subject: spi: ar934x: Don't leak SPI master in probe error path If the call to devm_spi_register_controller() fails on probe of the Qualcomm Atheros AR934x/QCA95xx SPI driver, the spi_controller struct is erroneously not freed. Fix by switching over to the new devm_spi_alloc_master() helper. Moreover, the controller's clock is enabled on probe but not disabled if any of the subsequent probe steps fail. Finally, there's an ordering issue in ar934x_spi_remove() wherein the clock is disabled even though the controller is not yet unregistered. It is unregistered after ar934x_spi_remove() by the devres framework. As long as it is not unregistered, SPI transfers may still be ongoing and disabling the clock may break them. It is not possible to use devm_spi_register_controller() in this case, so move to the non-devm variant. All of these bugs have existed since the driver was first introduced, so it seems fair to fix them together in a single commit. Fixes: 047980c582af ("spi: add driver for ar934x spi controller") Signed-off-by: Lukas Wunner Cc: # v5.7+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation Cc: # v5.7+ Cc: Chuanhong Guo Link: https://lore.kernel.org/r/1d58367d74d55741e0c2730a51a2b65012c8ab33.1607286887.git.lukas@wunner.de Signed-off-by: Mark Brown --- drivers/spi/spi-ar934x.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/spi/spi-ar934x.c b/drivers/spi/spi-ar934x.c index d08dec09d423..def32e0aaefe 100644 --- a/drivers/spi/spi-ar934x.c +++ b/drivers/spi/spi-ar934x.c @@ -176,10 +176,11 @@ static int ar934x_spi_probe(struct platform_device *pdev) if (ret) return ret; - ctlr = spi_alloc_master(&pdev->dev, sizeof(*sp)); + ctlr = devm_spi_alloc_master(&pdev->dev, sizeof(*sp)); if (!ctlr) { dev_info(&pdev->dev, "failed to allocate spi controller\n"); - return -ENOMEM; + ret = -ENOMEM; + goto err_clk_disable; } /* disable flash mapping and expose spi controller registers */ @@ -202,7 +203,13 @@ static int ar934x_spi_probe(struct platform_device *pdev) sp->clk_freq = clk_get_rate(clk); sp->ctlr = ctlr; - return devm_spi_register_controller(&pdev->dev, ctlr); + ret = spi_register_controller(ctlr); + if (!ret) + return 0; + +err_clk_disable: + clk_disable_unprepare(clk); + return ret; } static int ar934x_spi_remove(struct platform_device *pdev) @@ -213,6 +220,7 @@ static int ar934x_spi_remove(struct platform_device *pdev) ctlr = dev_get_drvdata(&pdev->dev); sp = spi_controller_get_devdata(ctlr); + spi_unregister_controller(ctlr); clk_disable_unprepare(sp->clk); return 0; -- cgit v1.2.3