Re: [PATCH RESEND] video: au1100fb: Move a variable assignment behind a null pointer check in au1100fb_setmode()

[Dan Carpenter]

On Mon, Mar 03, 2025 at 10:19:06AM +0100, Uwe Kleine-König wrote:
> Hello,
> 
> On Sun, Mar 02, 2025 at 07:02:12PM +0100, Markus Elfring wrote:
> > From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> > Date: Thu, 13 Apr 2023 21:35:36 +0200
> > 
> > The address of a data structure member was determined before
> > a corresponding null pointer check in the implementation of
> > the function “au1100fb_setmode”.
> > 
> > Thus avoid the risk for undefined behaviour by moving the assignment
> > for the variable “info” behind the null pointer check.
> > 
> > This issue was detected by using the Coccinelle software.
> > 
> > Fixes: 3b495f2bb749 ("Au1100 FB driver uplift for 2.6.")
> > Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> 
> Acked-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxx>
> 
> Should also get
> 
> Cc: stable@xxxxxxxxxxxxxxx
> 
> to ensure this is backported to stable.

It's not a bugfix, it's a cleanup.  That's not a dereference, it's
just pointer math.  It shouldn't have a Fixes tag.

Real bugs where we dereference a pointer and then check for NULL don't
last long in the kernel.  Most of the stuff Markus is sending is false
positives like this.

regards,
dan carpenter