lkml.org 
[lkml]   [2006]   [Nov]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Linux-fbdev-devel] fb: modedb uses wrong default_mode

> > I really don't trust dbsize. The driver writer can pass in the wrong
> > number.
>
> That would be a bug.

Excuse my paranoia about what driver writers will do :-/

> > Whereas ARRAY_SIZE will always be correct. Lets take the position
> > that we use dbsize then we need to test if dbsize is greater than the
> > really size of the modedb. The dbsize parameter was for the days before we
> > had ARRAY_SIZE.
> >
> > > int fb_find_mode(struct fb_var_screeninfo *var,
> > > struct fb_info *info, const char *mode_option,
> > > const struct fb_videomode *db, unsigned int dbsize,
> > > const struct fb_videomode *default_mode,
> > > unsigned int default_bpp)
> > > {
> > > int i;
> > >
> > > /* Set up defaults */
> > > if (!db) {
> > > db = modedb;
> > > dbsize = ARRAY_SIZE(modedb);
> > > }
> >
> > if (dbsize > ARRAY_SIZE(db))
> > dbsize = ARRAY_SIZE(db);
>
> We can't do ARRAY_SIZE on a random pointer like this: the compiler needs to
> see the full definition of the array itself, and that is back in the
> caller's compilation unit.

Good point about the pointer being valid. In that case we have to deal
with dbsize. Still nervous about going out of bounds of the array.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-11-20 21:39    [W:0.040 / U:30.764 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site