spi/bfin_spi: fix resources leakage

Re-order setup() a bit so we don't leak memory/dma/gpio resources upon
errors.  Also make sure we don't call kfree() twice on the same object.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index 10a6dc3..4f20b92 100644 (file)
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -1006,20 +1006,24 @@ static u16 ssel[][MAX_SPI_SSEL] = {
 /* first setup for new devices */
 static int bfin_spi_setup(struct spi_device *spi)
 {
-       struct bfin5xx_spi_chip *chip_info = NULL;
-       struct chip_data *chip;
+       struct bfin5xx_spi_chip *chip_info;
+       struct chip_data *chip = NULL;
        struct driver_data *drv_data = spi_master_get_devdata(spi->master);
-       int ret;
+       int ret = -EINVAL;
 
        if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
-               return -EINVAL;
+               goto error;
 
        /* Only alloc (or use chip_info) on first setup */
+       chip_info = NULL;
        chip = spi_get_ctldata(spi);
        if (chip == NULL) {
-               chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
-               if (!chip)
-                       return -ENOMEM;
+               chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+               if (!chip) {
+                       dev_err(&spi->dev, "cannot allocate chip data\n");
+                       ret = -ENOMEM;
+                       goto error;
+               }
 
                chip->enable_dma = 0;
                chip_info = spi->controller_data;
@@ -1036,7 +1040,7 @@ static int bfin_spi_setup(struct spi_device *spi)
                if (chip_info->ctl_reg & (SPE|MSTR|CPOL|CPHA|LSBF|SIZE)) {
                        dev_err(&spi->dev, "do not set bits in ctl_reg "
                                "that the SPI framework manages\n");
-                       return -EINVAL;
+                       goto error;
                }
 
                chip->enable_dma = chip_info->enable_dma != 0
@@ -1060,26 +1064,6 @@ static int bfin_spi_setup(struct spi_device *spi)
        chip->ctl_reg |= MSTR;
 
        /*
-        * if any one SPI chip is registered and wants DMA, request the
-        * DMA channel for it
-        */
-       if (chip->enable_dma && !drv_data->dma_requested) {
-               /* register dma irq handler */
-               if (request_dma(drv_data->dma_channel, "BFIN_SPI_DMA") < 0) {
-                       dev_dbg(&spi->dev,
-                               "Unable to request BlackFin SPI DMA channel\n");
-                       return -ENODEV;
-               }
-               if (set_dma_callback(drv_data->dma_channel,
-                   bfin_spi_dma_irq_handler, drv_data) < 0) {
-                       dev_dbg(&spi->dev, "Unable to set dma callback\n");
-                       return -EPERM;
-               }
-               dma_disable_irq(drv_data->dma_channel);
-               drv_data->dma_requested = 1;
-       }
-
-       /*
         * Notice: for blackfin, the speed_hz is the value of register
         * SPI_BAUD, not the real baudrate
         */
@@ -1087,16 +1071,6 @@ static int bfin_spi_setup(struct spi_device *spi)
        chip->flag = 1 << (spi->chip_select);
        chip->chip_select_num = spi->chip_select;
 
-       if (chip->chip_select_num == 0) {
-               ret = gpio_request(chip->cs_gpio, spi->modalias);
-               if (ret) {
-                       if (drv_data->dma_requested)
-                               free_dma(drv_data->dma_channel);
-                       return ret;
-               }
-               gpio_direction_output(chip->cs_gpio, 1);
-       }
-
        switch (chip->bits_per_word) {
        case 8:
                chip->n_bytes = 1;
@@ -1123,9 +1097,39 @@ static int bfin_spi_setup(struct spi_device *spi)
        default:
                dev_err(&spi->dev, "%d bits_per_word is not supported\n",
                                chip->bits_per_word);
-               if (chip_info)
-                       kfree(chip);
-               return -ENODEV;
+               goto error;
+       }
+
+       /*
+        * if any one SPI chip is registered and wants DMA, request the
+        * DMA channel for it
+        */
+       if (chip->enable_dma && !drv_data->dma_requested) {
+               /* register dma irq handler */
+               ret = request_dma(drv_data->dma_channel, "BFIN_SPI_DMA");
+               if (ret) {
+                       dev_err(&spi->dev,
+                               "Unable to request BlackFin SPI DMA channel\n");
+                       goto error;
+               }
+               drv_data->dma_requested = 1;
+
+               ret = set_dma_callback(drv_data->dma_channel,
+                       bfin_spi_dma_irq_handler, drv_data);
+               if (ret) {
+                       dev_err(&spi->dev, "Unable to set dma callback\n");
+                       goto error;
+               }
+               dma_disable_irq(drv_data->dma_channel);
+       }
+
+       if (chip->chip_select_num == 0) {
+               ret = gpio_request(chip->cs_gpio, spi->modalias);
+               if (ret) {
+                       dev_err(&spi->dev, "gpio_request() error\n");
+                       goto pin_error;
+               }
+               gpio_direction_output(chip->cs_gpio, 1);
        }
 
        dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d\n",
@@ -1136,14 +1140,38 @@ static int bfin_spi_setup(struct spi_device *spi)
        spi_set_ctldata(spi, chip);
 
        dev_dbg(&spi->dev, "chip select number is %d\n", chip->chip_select_num);
-       if ((chip->chip_select_num > 0)
-               && (chip->chip_select_num <= spi->master->num_chipselect))
-               peripheral_request(ssel[spi->master->bus_num]
-                       [chip->chip_select_num-1], spi->modalias);
+       if (chip->chip_select_num > 0 &&
+           chip->chip_select_num <= spi->master->num_chipselect) {
+               ret = peripheral_request(ssel[spi->master->bus_num]
+                                        [chip->chip_select_num-1], spi->modalias);
+               if (ret) {
+                       dev_err(&spi->dev, "peripheral_request() error\n");
+                       goto pin_error;
+               }
+       }
 
        bfin_spi_cs_deactive(drv_data, chip);
 
        return 0;
+
+ pin_error:
+       if (chip->chip_select_num == 0)
+               gpio_free(chip->cs_gpio);
+       else
+               peripheral_free(ssel[spi->master->bus_num]
+                       [chip->chip_select_num - 1]);
+ error:
+       if (chip) {
+               if (drv_data->dma_requested)
+                       free_dma(drv_data->dma_channel);
+               drv_data->dma_requested = 0;
+
+               kfree(chip);
+               /* prevent free 'chip' twice */
+               spi_set_ctldata(spi, NULL);
+       }
+
+       return ret;
 }
 
 /*
@@ -1166,6 +1194,8 @@ static void bfin_spi_cleanup(struct spi_device *spi)
                gpio_free(chip->cs_gpio);
 
        kfree(chip);
+       /* prevent free 'chip' twice */
+       spi_set_ctldata(spi, NULL);
 }
 
 static inline int bfin_spi_init_queue(struct driver_data *drv_data)