[PATCH 10/12] spi: gpio: Make sure spi_master_put() is called in every error path

[Andrey Smirnov]

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.smir...@gmail.com>
Cc: Mark Brown <broo...@kernel.org>
Cc: Chris Healy <cphe...@gmail.com>
Cc: linux-...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/spi/spi-gpio.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 3a6a9c6966c0..668f2cd82d98 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -363,6 +363,11 @@ 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;
@@ -378,6 +383,10 @@ 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
@@ -429,11 +438,7 @@ 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)
@@ -445,8 +450,6 @@ 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;
 }
 
-- 
2.20.1