drivers/video: bad error test before a dereference
authorJulien Brunel <brunel@diku.dk>
Wed, 19 Nov 2008 23:36:07 +0000 (15:36 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 20 Nov 2008 02:49:57 +0000 (18:49 -0800)
commitcf7b9a1e11993a064f445d332fecf22819b87a5e
treec9642ffcd59e666a882635e7cfb2b8dcb48b7fc1
parent9ca791bbd464d7968db1530b433cc397a4c348c1
drivers/video: bad error test before a dereference

The error test that follows the call to backlight_device_register semms
not to concern the right variable.

A simplified version of the semantic match that finds this problem is
as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@def0@
expression x;
position p0;
@@
x@p0 = backlight_device_register(...)

@protected@
expression def0.x,E;
position def0.p0;
position p;
statement S;
@@
x@p0
... when != x = E
if (!IS_ERR(x) && ...) {<... x@p ...>} else S

@unprotected@
expression def0.x;
identifier fld;
position def0.p0;
position p != protected.p;
@@
x@p0
... when != x = E
* x@p->fld
// </smpl>

Signed-off-by: Julien Brunel <brunel@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/video/atmel_lcdfb.c