spi: gpio: Make sure spi_master_put() is called in every error path

There's a number of failure paths in spi_gpio_probe() that do not call
spi_master_put() potentially leaking memory. Fix this problem by
registering a cleanup funciont via devm_add_action_or_reset() right
after SPI controller is allocated.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-spi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 5ac9ae1..d4a22f2 100644 (file)
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -362,6 +362,11 @@ static int spi_gpio_probe_pdata(struct platform_device *pdev,
        return 0;
 }
 
+static void spi_gpio_put(void *data)
+{
+       spi_master_put(data);
+}
+
 static int spi_gpio_probe(struct platform_device *pdev)
 {
        int                             status;
@@ -377,6 +382,10 @@ static int spi_gpio_probe(struct platform_device *pdev)
        if (!master)
                return -ENOMEM;
 
+       status = devm_add_action_or_reset(&pdev->dev, spi_gpio_put, master);
+       if (status)
+               return status;
+
        if (of_id)
                status = spi_gpio_probe_dt(pdev, master);
        else
@@ -428,11 +437,7 @@ static int spi_gpio_probe(struct platform_device *pdev)
        }
        bb->setup_transfer = spi_bitbang_setup_transfer;
 
-       status = spi_bitbang_start(&spi_gpio->bitbang);
-       if (status)
-               spi_master_put(master);
-
-       return status;
+       return spi_bitbang_start(&spi_gpio->bitbang);
 }
 
 static int spi_gpio_remove(struct platform_device *pdev)
@@ -444,8 +449,6 @@ static int spi_gpio_remove(struct platform_device *pdev)
        /* stop() unregisters child devices too */
        spi_bitbang_stop(&spi_gpio->bitbang);
 
-       spi_master_put(spi_gpio->bitbang.master);
-
        return 0;
 }