USB: cleanup ofd adutux

this driver does
- ignore errors during open
- submit a running urb
- use down_interruptible not handling signals
- GFP_KERNEL with a spinlock held

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 28 insertions, 20 deletions

diff --git a/drivers/usb/misc/adutux.c b/drivers/usb/misc/adutux.c
index 75bfab95ab3..77145f9db04 100644
--- a/drivers/usb/misc/adutux.c
+++ b/drivers/usb/misc/adutux.c
@@ -285,23 +285,24 @@ static int adu_open(struct inode *inode, struct file *file)
         /* save device in the file's private structure */
         file->private_data = dev;
 
-        /* initialize in direction */
-        dev->read_buffer_length = 0;
-
-        /* fixup first read by having urb waiting for it */
-        usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
-                         usb_rcvintpipe(dev->udev,
-                                        dev->interrupt_in_endpoint->bEndpointAddress),
-                         dev->interrupt_in_buffer,
-                         le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
-                         adu_interrupt_in_callback, dev,
-                         dev->interrupt_in_endpoint->bInterval);
-        /* dev->interrupt_in_urb->transfer_flags |= URB_ASYNC_UNLINK; */
-        dev->read_urb_finished = 0;
-        usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
-        /* we ignore failure */
-        /* end of fixup for first read */
+        if (dev->open_count == 1) {
+                /* initialize in direction */
+                dev->read_buffer_length = 0;
 
+                /* fixup first read by having urb waiting for it */
+                usb_fill_int_urb(dev->interrupt_in_urb,dev->udev,
+                                 usb_rcvintpipe(dev->udev,
+                                                dev->interrupt_in_endpoint->bEndpointAddress),
+                                 dev->interrupt_in_buffer,
+                                 le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize),
+                                 adu_interrupt_in_callback, dev,
+                                 dev->interrupt_in_endpoint->bInterval);
+                /* dev->interrupt_in_urb->transfer_flags |= URB_ASYNC_UNLINK; */
+                dev->read_urb_finished = 0;
+                retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
+                if (retval)
+                        --dev->open_count;
+        }
         up(&dev->sem);
 
 exit_no_device:
@@ -469,7 +470,7 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
                                                          adu_interrupt_in_callback,
                                                          dev,
                                                          dev->interrupt_in_endpoint->bInterval);
-                                        retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
+                                        retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
                                         if (!retval) {
                                                 spin_unlock_irqrestore(&dev->buflock, flags);
                                                 dbg(2," %s : submitted OK", __FUNCTION__);
@@ -539,7 +540,7 @@ static ssize_t adu_write(struct file *file, const __user char *buffer,
         size_t bytes_written = 0;
         size_t bytes_to_write;
         size_t buffer_size;
-        int retval = 0;
+        int retval;
         int timeout = 0;
 
         dbg(2," %s : enter, count = %Zd", __FUNCTION__, count);
@@ -547,7 +548,9 @@ static ssize_t adu_write(struct file *file, const __user char *buffer,
         dev = file->private_data;
 
         /* lock this object */
-        down_interruptible(&dev->sem);
+        retval = down_interruptible(&dev->sem);
+        if (retval)
+                goto exit_nolock;
 
         /* verify that the device wasn't unplugged */
         if (dev->udev == NULL || dev->minor == 0) {
@@ -575,7 +578,11 @@ static ssize_t adu_write(struct file *file, const __user char *buffer,
                         }
                         up(&dev->sem);
                         timeout = interruptible_sleep_on_timeout(&dev->write_wait, timeout);
-                        down_interruptible(&dev->sem);
+                        retval = down_interruptible(&dev->sem);
+                        if (retval) {
+                                retval = bytes_written ? bytes_written : retval;
+                                goto exit_nolock;
+                        }
                         if (timeout > 0) {
                                 break;
                         }
@@ -637,6 +644,7 @@ static ssize_t adu_write(struct file *file, const __user char *buffer,
 exit:
         /* unlock the device */
         up(&dev->sem);
+exit_nolock:
 
         dbg(2," %s : leave, return value %d", __FUNCTION__, retval);