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>

1 files changed, 75 insertions, 45 deletions

diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index 10a6dc3d37ac..4f20b923a95c 100644
--- 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)