V4L/DVB (9194): stk-webcam: fix crash on close after disconnect

This patch prevents stk-webcam from updating usb device information
once the camera has been removed. This prevents a crash that would
otherwise occur if the camera is disconnected while it is still in
use.

Signed-off-by: David Ellingsworth <david@identd.dyndns.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 7 insertions, 11 deletions

diff --git a/drivers/media/video/stk-webcam.c b/drivers/media/video/stk-webcam.c
index f1d5b3eaa192..edaea4964513 100644
--- a/drivers/media/video/stk-webcam.c
+++ b/drivers/media/video/stk-webcam.c
@@ -559,7 +559,7 @@ static void stk_clean_iso(struct stk_camera *dev)
 
                 urb = dev->isobufs[i].urb;
                 if (urb) {
-                        if (atomic_read(&dev->urbs_used))
+                        if (atomic_read(&dev->urbs_used) && is_present(dev))
                                 usb_kill_urb(urb);
                         usb_free_urb(urb);
                 }
@@ -688,18 +688,14 @@ static int v4l_stk_release(struct inode *inode, struct file *fp)
 {
         struct stk_camera *dev = fp->private_data;
 
-        if (dev->owner != fp) {
-                usb_autopm_put_interface(dev->interface);
-                return 0;
+        if (dev->owner == fp) {
+                stk_stop_stream(dev);
+                stk_free_buffers(dev);
+                dev->owner = NULL;
         }
 
-        stk_stop_stream(dev);
-
-        stk_free_buffers(dev);
-
-        dev->owner = NULL;
-
-        usb_autopm_put_interface(dev->interface);
+        if(is_present(dev))
+                usb_autopm_put_interface(dev->interface);
 
         return 0;
 }