[media] pwc: Remove a bunch of bogus sanity checks / don't return EFAULT wrongly

The chances if any of these becoming NULL magically are 0% And if they
do become NULL oopsing is the right thing to do (so that the user logs a
bug with the kernel rather then with whatever app he was using).

Returning EFAULT to userspace should only be done when userspace supplies
a bad address, not on driver bugs / hw issues, so in the few cases where the
check is not bogus return something else.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/video/pwc/pwc-if.c b/drivers/media/video/pwc/pwc-if.c
index b0bde5a..3d3ff60 100644 (file)
--- a/drivers/media/video/pwc/pwc-if.c
+++ b/drivers/media/video/pwc/pwc-if.c
@@ -226,9 +226,6 @@ static int pwc_allocate_buffers(struct pwc_device *pdev)
 
        PWC_DEBUG_MEMORY(">> pwc_allocate_buffers(pdev = 0x%p)\n", pdev);
 
-       if (pdev == NULL)
-               return -ENXIO;
-
        /* Allocate Isochronuous pipe buffers */
        for (i = 0; i < MAX_ISO_BUFS; i++) {
                if (pdev->sbuf[i].data == NULL) {
@@ -306,8 +303,6 @@ static void pwc_free_buffers(struct pwc_device *pdev)
 
        PWC_DEBUG_MEMORY("Entering free_buffers(%p).\n", pdev);
 
-       if (pdev == NULL)
-               return;
        /* Release Iso-pipe buffers */
        for (i = 0; i < MAX_ISO_BUFS; i++)
                if (pdev->sbuf[i].data != NULL) {
@@ -783,26 +778,20 @@ int pwc_isoc_init(struct pwc_device *pdev)
        struct usb_device *udev;
        struct urb *urb;
        int i, j, ret;
-
        struct usb_interface *intf;
        struct usb_host_interface *idesc = NULL;
 
-       if (pdev == NULL)
-               return -EFAULT;
        if (pdev->iso_init)
                return 0;
        pdev->vsync = 0;
        udev = pdev->udev;
 
        /* Get the current alternate interface, adjust packet size */
-       if (!udev->actconfig)
-               return -EFAULT;
        intf = usb_ifnum_to_if(udev, 0);
        if (intf)
                idesc = usb_altnum_to_altsetting(intf, pdev->valternate);
-
        if (!idesc)
-               return -EFAULT;
+               return -EIO;
 
        /* Search video endpoint */
        pdev->vmax_packet_size = -1;
@@ -918,8 +907,7 @@ static void pwc_iso_free(struct pwc_device *pdev)
 void pwc_isoc_cleanup(struct pwc_device *pdev)
 {
        PWC_DEBUG_OPEN(">> pwc_isoc_cleanup()\n");
-       if (pdev == NULL)
-               return;
+
        if (pdev->iso_init == 0)
                return;
 
@@ -1058,7 +1046,6 @@ static int pwc_video_open(struct file *file)
        PWC_DEBUG_OPEN(">> video_open called(vdev = 0x%p).\n", vdev);
 
        pdev = video_get_drvdata(vdev);
-       BUG_ON(!pdev);
        if (pdev->vopen) {
                PWC_DEBUG_OPEN("I'm busy, someone is using the device.\n");
                return -EBUSY;
@@ -1230,11 +1217,7 @@ static ssize_t pwc_video_read(struct file *file, char __user *buf,
 
        PWC_DEBUG_READ("pwc_video_read(vdev=0x%p, buf=%p, count=%zd) called.\n",
                        vdev, buf, count);
-       if (vdev == NULL)
-               return -EFAULT;
        pdev = video_get_drvdata(vdev);
-       if (pdev == NULL)
-               return -EFAULT;
 
        if (pdev->error_status) {
                rv = -pdev->error_status; /* Something happened, report what. */
@@ -1279,10 +1262,9 @@ static ssize_t pwc_video_read(struct file *file, char __user *buf,
                set_current_state(TASK_RUNNING);
 
                /* Decompress and release frame */
-               if (pwc_handle_frame(pdev)) {
-                       rv = -EFAULT;
+               rv = pwc_handle_frame(pdev);
+               if (rv)
                        goto err_out;
-               }
        }
 
        PWC_DEBUG_READ("Copying data to user space.\n");
@@ -1317,11 +1299,7 @@ static unsigned int pwc_video_poll(struct file *file, poll_table *wait)
        struct pwc_device *pdev;
        int ret;
 
-       if (vdev == NULL)
-               return -EFAULT;
        pdev = video_get_drvdata(vdev);
-       if (pdev == NULL)
-               return -EFAULT;
 
        /* Start the stream (if not already started) */
        ret = pwc_isoc_init(pdev);
@@ -1769,18 +1747,6 @@ static void usb_pwc_disconnect(struct usb_interface *intf)
 
        mutex_lock(&pdev->modlock);
        usb_set_intfdata (intf, NULL);
-       if (pdev == NULL) {
-               PWC_ERROR("pwc_disconnect() Called without private pointer.\n");
-               goto disconnect_out;
-       }
-       if (pdev->udev == NULL) {
-               PWC_ERROR("pwc_disconnect() already called for %p\n", pdev);
-               goto disconnect_out;
-       }
-       if (pdev->udev != interface_to_usbdev(intf)) {
-               PWC_ERROR("pwc_disconnect() Woops: pointer mismatch udev/pdev.\n");
-               goto disconnect_out;
-       }
 
        /* We got unplugged; this is signalled by an EPIPE error code */
        pdev->error_status = EPIPE;
@@ -1792,7 +1758,6 @@ static void usb_pwc_disconnect(struct usb_interface *intf)
        /* No need to keep the urbs around after disconnection */
        pwc_isoc_cleanup(pdev);
 
-disconnect_out:
        mutex_unlock(&pdev->modlock);
 
        pwc_remove_sysfs_files(pdev);

diff --git a/drivers/media/video/pwc/pwc-uncompress.c b/drivers/media/video/pwc/pwc-uncompress.c
index 3b73f29..4118184 100644 (file)
--- a/drivers/media/video/pwc/pwc-uncompress.c
+++ b/drivers/media/video/pwc/pwc-uncompress.c
@@ -42,12 +42,7 @@ int pwc_decompress(struct pwc_device *pdev)
        u16 *src;
        u16 *dsty, *dstu, *dstv;
 
-       if (pdev == NULL)
-               return -EFAULT;
-
        fbuf = pdev->read_frame;
-       if (fbuf == NULL)
-               return -EFAULT;
        image  = pdev->image_data;
        image += pdev->images[pdev->fill_image].offset;
 

diff --git a/drivers/media/video/pwc/pwc-v4l.c b/drivers/media/video/pwc/pwc-v4l.c
index 059bd95..8e72e0f 100644 (file)
--- a/drivers/media/video/pwc/pwc-v4l.c
+++ b/drivers/media/video/pwc/pwc-v4l.c
@@ -778,7 +778,7 @@ static int pwc_dqbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
        /* Decompress data in pdev->images[pdev->fill_image] */
        ret = pwc_handle_frame(pdev);
        if (ret)
-               return -EFAULT;
+               return ret;
        PWC_DEBUG_IOCTL("VIDIOC_DQBUF: after pwc_handle_frame\n");
 
        buf->index = pdev->fill_image;