[ldv-project] [PATCH] [media] gspca: fix dev_open() error path

[Alexey Khoroshilov]

If v4l2_fh_open() fails in dev_open(), gspca_dev->module left locked.
The patch adds module_put(gspca_dev->module) on this path.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov at ispras.ru>
---
 drivers/media/usb/gspca/gspca.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/media/usb/gspca/gspca.c b/drivers/media/usb/gspca/gspca.c
index b7ae872..048507b 100644
--- a/drivers/media/usb/gspca/gspca.c
+++ b/drivers/media/usb/gspca/gspca.c
@@ -1266,6 +1266,7 @@ static void gspca_release(struct v4l2_device *v4l2_device)
 static int dev_open(struct file *file)
 {
 	struct gspca_dev *gspca_dev = video_drvdata(file);
+	int ret;
 
 	PDEBUG(D_STREAM, "[%s] open", current->comm);
 
@@ -1273,7 +1274,10 @@ static int dev_open(struct file *file)
 	if (!try_module_get(gspca_dev->module))
 		return -ENODEV;
 
-	return v4l2_fh_open(file);
+	ret = v4l2_fh_open(file);
+	if (ret)
+		module_put(gspca_dev->module);
+	return ret;
 }
 
 static int dev_close(struct file *file)
-- 
1.8.1.2