staging: comedi: only set dev->n_subdevices when kcalloc succeedes

It's possible for the kcalloc in comedi_alloc_subdevices to fail.
Only set the dev->n_subdevices variable if the allocation is
successful.

Since the core sets dev->n_subdevices, remove all the places in the
drivers where this variable was getting set.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbott@mev.co.uk>
Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
index 61161ce8e93f58d764bdac5fb592be1c9d0727b3..ecad2288c9fbf6d0e036717591d4ab092ba6a1ab 100644 (file)
--- a/drivers/staging/comedi/drivers.c
+++ b/drivers/staging/comedi/drivers.c
@@ -62,12 +62,12 @@ int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
 
        if (num_subdevices < 1)
                return -EINVAL;
-       dev->n_subdevices = num_subdevices;
        dev->subdevices =
            kcalloc(num_subdevices, sizeof(struct comedi_subdevice),
                    GFP_KERNEL);
        if (!dev->subdevices)
                return -ENOMEM;
+       dev->n_subdevices = num_subdevices;
        for (i = 0; i < num_subdevices; ++i) {
                dev->subdevices[i].device = dev;
                dev->subdevices[i].async_dma_dir = DMA_NONE;

diff --git a/drivers/staging/comedi/drivers/comedi_test.c b/drivers/staging/comedi/drivers/comedi_test.c
index cd43c0d7df389b13306f77e5e29386a7db78a0ec..004da30d7d2b5e55d9adc3b79084a32efa1a53de 100644 (file)
--- a/drivers/staging/comedi/drivers/comedi_test.c
+++ b/drivers/staging/comedi/drivers/comedi_test.c
@@ -447,8 +447,7 @@ static int waveform_attach(struct comedi_device *dev,
        devpriv->uvolt_amplitude = amplitude;
        devpriv->usec_period = period;
 
-       dev->n_subdevices = 2;
-       if (comedi_alloc_subdevices(dev, dev->n_subdevices) < 0)
+       if (comedi_alloc_subdevices(dev, 2) < 0)
                return -ENOMEM;
 
        s = dev->subdevices + 0;

diff --git a/drivers/staging/comedi/drivers/ni_660x.c b/drivers/staging/comedi/drivers/ni_660x.c
index 5827debd33668aadcc998ea2e54b5bb6c2c90d4f..8c6a6ba9d4b9b2cfd92ea627c4c5fca2383f094d 100644 (file)
--- a/drivers/staging/comedi/drivers/ni_660x.c
+++ b/drivers/staging/comedi/drivers/ni_660x.c
@@ -1093,9 +1093,7 @@ static int ni_660x_attach(struct comedi_device *dev,
 
        printk(KERN_INFO " %s ", dev->board_name);
 
-       dev->n_subdevices = 2 + NI_660X_MAX_NUM_COUNTERS;
-
-       if (comedi_alloc_subdevices(dev, dev->n_subdevices) < 0)
+       if (comedi_alloc_subdevices(dev, 2 + NI_660X_MAX_NUM_COUNTERS) < 0)
                return -ENOMEM;
 
        s = dev->subdevices + 0;

diff --git a/drivers/staging/comedi/drivers/s526.c b/drivers/staging/comedi/drivers/s526.c
index 17d581b8ac6fccf52b6bdb44b3661bbda5094695..dbbff70dc0ca9777d28841299cabcf60720812ad 100644 (file)
--- a/drivers/staging/comedi/drivers/s526.c
+++ b/drivers/staging/comedi/drivers/s526.c
@@ -778,8 +778,7 @@ static int s526_attach(struct comedi_device *dev, struct comedi_devconfig *it)
  * Allocate the subdevice structures.  alloc_subdevice() is a
  * convenient macro defined in comedidev.h.
  */
-       dev->n_subdevices = 4;
-       if (comedi_alloc_subdevices(dev, dev->n_subdevices) < 0)
+       if (comedi_alloc_subdevices(dev, 4) < 0)
                return -ENOMEM;
 
        s = dev->subdevices + 0;

diff --git a/drivers/staging/comedi/drivers/usbdux.c b/drivers/staging/comedi/drivers/usbdux.c
index ca8b3e121ff01dabda3563583410ab737a1274ba..3819663b1cbe9e77121d4289b6a78ce9928128d8 100644 (file)
--- a/drivers/staging/comedi/drivers/usbdux.c
+++ b/drivers/staging/comedi/drivers/usbdux.c
@@ -2624,6 +2624,7 @@ static int usbdux_attach_common(struct comedi_device *dev,
 {
        int ret;
        struct comedi_subdevice *s = NULL;
+       int n_subdevs;
 
        down(&udev->sem);
        /* pointer back to the corresponding comedi device */
@@ -2638,14 +2639,14 @@ static int usbdux_attach_common(struct comedi_device *dev,
        /* set number of subdevices */
        if (udev->high_speed) {
                /* with pwm */
-               dev->n_subdevices = 5;
+               n_subdevs = 5;
        } else {
                /* without pwm */
-               dev->n_subdevices = 4;
+               n_subdevs = 4;
        }
 
        /* allocate space for the subdevices */
-       ret = comedi_alloc_subdevices(dev, dev->n_subdevices);
+       ret = comedi_alloc_subdevices(dev, n_subdevs);
        if (ret < 0) {
                dev_err(&udev->interface->dev,
                        "comedi%d: error alloc space for subdev\n", dev->minor);

diff --git a/drivers/staging/comedi/drivers/usbduxfast.c b/drivers/staging/comedi/drivers/usbduxfast.c
index b2f7350c429feebc3fdf56e8ab30ff497e421068..262556ebc4db3f4eea1a46bb3c0c74f005690809 100644 (file)
--- a/drivers/staging/comedi/drivers/usbduxfast.c
+++ b/drivers/staging/comedi/drivers/usbduxfast.c
@@ -126,11 +126,6 @@
  */
 #define NUMUSBDUXFAST  16
 
-/*
- * number of subdevices
- */
-#define N_SUBDEVICES   1
-
 /*
  * analogue in subdevice
  */
@@ -1671,11 +1666,8 @@ static int usbduxfast_attach(struct comedi_device *dev,
 
        dev->board_name = BOARDNAME;
 
-       /* set number of subdevices */
-       dev->n_subdevices = N_SUBDEVICES;
-
        /* allocate space for the subdevices */
-       ret = comedi_alloc_subdevices(dev, N_SUBDEVICES);
+       ret = comedi_alloc_subdevices(dev, 1);
        if (ret < 0) {
                printk(KERN_ERR "comedi%d: usbduxfast: error alloc space for "
                       "subdev\n", dev->minor);

diff --git a/drivers/staging/comedi/drivers/usbduxsigma.c b/drivers/staging/comedi/drivers/usbduxsigma.c
index 00faf4ad6ffb56740530e659df5261e242505f0a..87c613e8889293b3f3c005f275f948e492309f9c 100644 (file)
--- a/drivers/staging/comedi/drivers/usbduxsigma.c
+++ b/drivers/staging/comedi/drivers/usbduxsigma.c
@@ -2642,6 +2642,7 @@ static int usbduxsigma_attach(struct comedi_device *dev,
        int index;
        int i;
        struct usbduxsub *udev;
+       int n_subdevs;
 
        int offset;
 
@@ -2683,14 +2684,14 @@ static int usbduxsigma_attach(struct comedi_device *dev,
        /* set number of subdevices */
        if (udev->high_speed) {
                /* with pwm */
-               dev->n_subdevices = 4;
+               n_subdevs = 4;
        } else {
                /* without pwm */
-               dev->n_subdevices = 3;
+               n_subdevs = 3;
        }
 
        /* allocate space for the subdevices */
-       ret = comedi_alloc_subdevices(dev, dev->n_subdevices);
+       ret = comedi_alloc_subdevices(dev, n_subdevs);
        if (ret < 0) {
                dev_err(&udev->interface->dev,
                        "comedi%d: no space for subdev\n", dev->minor);