lkml.org 
[lkml]   [2009]   [Aug]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 3/3] drivers/scsi: Add kmalloc NULL tests
On Thu, 6 Aug 2009, James Bottomley wrote:

> On Thu, 2009-08-06 at 22:06 +0200, Julia Lawall wrote:
> > From: Julia Lawall <julia@diku.dk>
> >
> > Check that the result of kmalloc is not NULL before passing it to other
> > functions.
> >
> > The semantic match that finds this problem is as follows:
> > (http://coccinelle.lip6.fr/)
> >
> > // <smpl>
> > @@
> > expression *x;
> > identifier f;
> > constant char *C;
> > @@
> >
> > x = \(kmalloc\|kcalloc\|kzalloc\)(...);
> > ... when != x == NULL
> > when != x != NULL
> > when != (x || ...)
> > (
> > kfree(x)
> > |
> > f(...,C,...,x,...)
> > |
> > *f(...,x,...)
> > |
> > *x->f
> > )
> > // </smpl>
> >
> > Signed-off-by: Julia Lawall <julia@diku.dk>
> >
> > ---
> > drivers/scsi/sr.c | 2 ++
> > 1 files changed, 2 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
> > index cce0fe4..3fbf42e 100644
> > --- a/drivers/scsi/sr.c
> > +++ b/drivers/scsi/sr.c
> > @@ -211,6 +211,8 @@ static int sr_media_change(struct cdrom_device_info *cdi, int slot)
> > }
> >
> > sshdr = kzalloc(sizeof(*sshdr), GFP_KERNEL);
> > + if (!sshdr)
> > + return -ENOMEM;
>
> this isn't necessary; sr_test_unit_ready is designed to take a NULL
> pointer for sshdr ... it's just slightly less useful when this happens,
> but it still returns some status.

OK, I agree. Thanks.

julia


\
 
 \ /
  Last update: 2009-08-07 06:43    [W:0.032 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site