From: Bernd Porr <[email protected]> ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. -------------------
commit 3ffab428f40849ed5f21bcfd7285bdef7902f9ca upstream. This fixes kernel oops when an USB DAQ device is plugged out while it's communicating with the userspace software. Signed-off-by: Bernd Porr <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Paul Gortmaker <[email protected]> --- drivers/staging/comedi/comedi_fops.c | 71 +++++++++++++++++++++++++++--------- 1 file changed, 53 insertions(+), 18 deletions(-) diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index ac6527c..48ac52b 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -1391,9 +1391,6 @@ static struct vm_operations_struct comedi_vm_ops = { static int comedi_mmap(struct file *file, struct vm_area_struct *vma) { const unsigned minor = iminor(file->f_dentry->d_inode); - struct comedi_device_file_info *dev_file_info = - comedi_get_device_file_info(minor); - struct comedi_device *dev = dev_file_info->device; struct comedi_async *async = NULL; unsigned long start = vma->vm_start; unsigned long size; @@ -1401,6 +1398,15 @@ static int comedi_mmap(struct file *file, struct vm_area_struct *vma) int i; int retval; struct comedi_subdevice *s; + struct comedi_device_file_info *dev_file_info; + struct comedi_device *dev; + + dev_file_info = comedi_get_device_file_info(minor); + if (dev_file_info == NULL) + return -ENODEV; + dev = dev_file_info->device; + if (dev == NULL) + return -ENODEV; mutex_lock(&dev->mutex); if (!dev->attached) { @@ -1467,11 +1473,17 @@ static unsigned int comedi_poll(struct file *file, poll_table * wait) { unsigned int mask = 0; const unsigned minor = iminor(file->f_dentry->d_inode); - struct comedi_device_file_info *dev_file_info = - comedi_get_device_file_info(minor); - struct comedi_device *dev = dev_file_info->device; struct comedi_subdevice *read_subdev; struct comedi_subdevice *write_subdev; + struct comedi_device_file_info *dev_file_info; + struct comedi_device *dev; + dev_file_info = comedi_get_device_file_info(minor); + + if (dev_file_info == NULL) + return -ENODEV; + dev = dev_file_info->device; + if (dev == NULL) + return -ENODEV; mutex_lock(&dev->mutex); if (!dev->attached) { @@ -1517,9 +1529,15 @@ static ssize_t comedi_write(struct file *file, const char *buf, size_t nbytes, int n, m, count = 0, retval = 0; DECLARE_WAITQUEUE(wait, current); const unsigned minor = iminor(file->f_dentry->d_inode); - struct comedi_device_file_info *dev_file_info = - comedi_get_device_file_info(minor); - struct comedi_device *dev = dev_file_info->device; + struct comedi_device_file_info *dev_file_info; + struct comedi_device *dev; + dev_file_info = comedi_get_device_file_info(minor); + + if (dev_file_info == NULL) + return -ENODEV; + dev = dev_file_info->device; + if (dev == NULL) + return -ENODEV; if (!dev->attached) { DPRINTK("no driver configured on comedi%i\n", dev->minor); @@ -1619,9 +1637,15 @@ static ssize_t comedi_read(struct file *file, char *buf, size_t nbytes, int n, m, count = 0, retval = 0; DECLARE_WAITQUEUE(wait, current); const unsigned minor = iminor(file->f_dentry->d_inode); - struct comedi_device_file_info *dev_file_info = - comedi_get_device_file_info(minor); - struct comedi_device *dev = dev_file_info->device; + struct comedi_device_file_info *dev_file_info; + struct comedi_device *dev; + dev_file_info = comedi_get_device_file_info(minor); + + if (dev_file_info == NULL) + return -ENODEV; + dev = dev_file_info->device; + if (dev == NULL) + return -ENODEV; if (!dev->attached) { DPRINTK("no driver configured on comedi%i\n", dev->minor); @@ -1814,11 +1838,17 @@ ok: static int comedi_close(struct inode *inode, struct file *file) { const unsigned minor = iminor(inode); - struct comedi_device_file_info *dev_file_info = - comedi_get_device_file_info(minor); - struct comedi_device *dev = dev_file_info->device; struct comedi_subdevice *s = NULL; int i; + struct comedi_device_file_info *dev_file_info; + struct comedi_device *dev; + dev_file_info = comedi_get_device_file_info(minor); + + if (dev_file_info == NULL) + return -ENODEV; + dev = dev_file_info->device; + if (dev == NULL) + return -ENODEV; mutex_lock(&dev->mutex); @@ -1852,10 +1882,15 @@ static int comedi_close(struct inode *inode, struct file *file) static int comedi_fasync(int fd, struct file *file, int on) { const unsigned minor = iminor(file->f_dentry->d_inode); - struct comedi_device_file_info *dev_file_info = - comedi_get_device_file_info(minor); + struct comedi_device_file_info *dev_file_info; + struct comedi_device *dev; + dev_file_info = comedi_get_device_file_info(minor); - struct comedi_device *dev = dev_file_info->device; + if (dev_file_info == NULL) + return -ENODEV; + dev = dev_file_info->device; + if (dev == NULL) + return -ENODEV; return fasync_helper(fd, file, on, &dev->async_queue); } -- 1.7.12.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
