From: Julia Lawall <julia@diku.dk>
The variable report is only non-NULL and non-freed in a small region of
code, so it should only be freed in error handling code that comes from
that region.
This was found using the following semantic match.
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@r1@
expression E;
position p1,p2;
@@
kfree@p1(E);
...
kfree@p2(E);
@subexps@
expression E1;
position r1.p1,p;
@@
kfree@p1(<+... E1@p ...+>);
@recollect@
position subexps.p;
expression E1;
@@
E1@p
@doublekfree@
position r1.p1,r1.p2;
expression recollect.E1,E2,E;
position p;
statement S;
@@
kfree@p1(E);
<+... E1@p=E2 ...+> // the actual semantic match contains other assignments
kfree@p2(E);
@notdoublekfree@
position r1.p1,r1.p2;
position any doublekfree.p;
expression E,E1,E2;
@@
* kfree@p1(E);
... when != E1@p
when != E1@p = E2 // needed to match a variable decl
* kfree@p2(E);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
---
diff -u -p a/drivers/input/tablet/gtco.c b/drivers/input/tablet/gtco.c
--- a/drivers/input/tablet/gtco.c 2008-05-09 16:46:57.000000000 +0200
+++ b/drivers/input/tablet/gtco.c 2008-05-29 14:12:31.000000000 +0200
@@ -926,7 +926,7 @@ static int gtco_probe(struct usb_interfa
err("Failed to get HID Report Descriptor of size: %d",
hid_desc->wDescriptorLength);
error = -EIO;
- goto err_free_urb;
+ goto err_free_report;
}
/* Now we parse the report */
@@ -982,13 +982,14 @@ static int gtco_probe(struct usb_interfa
return 0;
+ err_free_report:
+ kfree(report);
err_free_urb:
usb_free_urb(gtco->urbinfo);
err_free_buf:
usb_buffer_free(gtco->usbdev, REPORT_MAX_SIZE,
gtco->buffer, gtco->buf_dma);
err_free_devs:
- kfree(report);
input_free_device(input_dev);
kfree(gtco);
return error;
--
