Commit cd0e280f authored Nov 21, 2009 by Julia Lawall Committed by Mauro Carvalho Chehab Dec 05, 2009

V4L/DVB (13413): introduce missing kfree

Error handling code following a kzalloc should free the allocated data.
Similarly for usb-alloc urb.

The semantic match that finds the first problem is as follows:
(http://www.emn.fr/x-info/coccinelle/

)

// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

parent c95a419a

drivers/media/video/hdpvr/hdpvr-video.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -139,7 +139,7 @@ int hdpvr_alloc_buffers(struct hdpvr_device *dev, uint count)
		urb = usb_alloc_urb(0, GFP_KERNEL);
		if (!urb) {
		v4l2_err(&dev->v4l2_dev, "cannot allocate urb\n");
		goto exit;
		goto exit_urb;
		}
		buf->urb = urb;

		@@ -148,7 +148,7 @@ int hdpvr_alloc_buffers(struct hdpvr_device *dev, uint count)
		if (!mem) {
		v4l2_err(&dev->v4l2_dev,
		"cannot allocate usb transfer buffer\n");
		goto exit;
		goto exit_urb_buffer;
		}

		usb_fill_bulk_urb(buf->urb, dev->udev,
		@@ -161,6 +161,10 @@ int hdpvr_alloc_buffers(struct hdpvr_device *dev, uint count)
		list_add_tail(&buf->buff_list, &dev->free_buff_list);
		}
		return 0;
		exit_urb_buffer:
		usb_free_urb(urb);
		exit_urb:
		kfree(buf);
		exit:
		hdpvr_free_buffers(dev);
		return retval;