From 9649803f2de0d2e77bdd7c5e1cbd4a7b3833f1e8 Mon Sep 17 00:00:00 2001 From: Bernd Porr Date: Tue, 8 Nov 2011 21:23:03 +0000 Subject: [PATCH] staging: comedi: fix oops for USB DAQ devices. 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 Signed-off-by: Greg Kroah-Hartman --- 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 c20694e65157..2cbb17945c51 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -1452,9 +1452,6 @@ 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; @@ -1462,6 +1459,15 @@ 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) { @@ -1528,11 +1534,17 @@ 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) { @@ -1578,9 +1590,15 @@ static ssize_t comedi_write(struct file *file, const char __user *buf, 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); @@ -1683,9 +1701,15 @@ static ssize_t comedi_read(struct file *file, char __user *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); @@ -1885,11 +1909,17 @@ 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); @@ -1923,10 +1953,15 @@ 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); } -- 2.34.1