[PATCH] USB: fix usb-skeleton limit resource usage patch.

Prevents a compiler warning and uses down_interruptible() instead of down() in
process context.

Signed-off-by: Sam Bishop <sam@bishop.dhs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/usb/usb-skeleton.c b/drivers/usb/usb-skeleton.c
index b6652ef56830..5d02f16b7d0e 100644
--- a/drivers/usb/usb-skeleton.c
+++ b/drivers/usb/usb-skeleton.c
@@ -166,7 +166,7 @@ static ssize_t skel_write(struct file *file, const char *user_buffer, size_t cou
         int retval = 0;
         struct urb *urb = NULL;
         char *buf = NULL;
-        size_t writesize = min(count, MAX_TRANSFER);
+        size_t writesize = min(count, (size_t)MAX_TRANSFER);
 
         dev = (struct usb_skel *)file->private_data;
 
@@ -175,7 +175,10 @@ static ssize_t skel_write(struct file *file, const char *user_buffer, size_t cou
                 goto exit;
 
         /* limit the number of URBs in flight to stop a user from using up all RAM */
-        down (&dev->limit_sem);
+        if (down_interruptible(&dev->limit_sem)) {
+                retval = -ERESTARTSYS;
+                goto exit;
+        }
 
         /* create a urb, and a buffer for it, and copy the data to the urb */
         urb = usb_alloc_urb(0, GFP_KERNEL);