On Sun, 13 Dec 2009, walter harms wrote: > > > Julia Lawall schrieb: > > From: Julia Lawall <julia@xxxxxxx> > > > > sizeof(codec->reg_cache) is just the size of the pointer. Elsewhere in the > > file, codec->reg_cache is used with sizeof(wm8900_reg_defaults), so the > > code is changed to do the same here. > > > > A simplified version of the semantic patch that finds this problem is as > > follows: (http://coccinelle.lip6.fr/) > > > > // <smpl> > > @@ > > expression *x; > > expression f; > > type T; > > @@ > > > > *f(...,(T)x,...) > > // </smpl> > > > > Signed-off-by: Julia Lawall <julia@xxxxxxx> > > > > --- > > sound/soc/codecs/wm8900.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/sound/soc/codecs/wm8900.c b/sound/soc/codecs/wm8900.c > > index c9438dd..dbc368c 100644 > > --- a/sound/soc/codecs/wm8900.c > > +++ b/sound/soc/codecs/wm8900.c > > @@ -199,7 +199,7 @@ static void wm8900_reset(struct snd_soc_codec *codec) > > snd_soc_write(codec, WM8900_REG_RESET, 0); > > > > memcpy(codec->reg_cache, wm8900_reg_defaults, > > - sizeof(codec->reg_cache)); > > + sizeof(wm8900_reg_defaults)); > > } > > I do not think that this was the intention of the original author, > I guess the idea behind sizeof(*codec->reg_cache) was to protect > the area behind it (in case wm8900_reg_defaults are badly defined). sizeof(codec->reg_cache) is the size of a pointer (void *). sizeof(*codec->reg_cache) is then the size of void. wm8900_reg_defaults is a static constant array defined a few lines before this code: static const u16 wm8900_reg_defaults[WM8900_MAXREG] = { ... }; Later in the same file there is: cache = kmemdup(codec->reg_cache, sizeof(wm8900_reg_defaults), GFP_KERNEL); and codec->reg_cache is initialized as follows: codec->reg_cache = &wm8900->reg_cache[0]; The reg_cache field in wm8900 is declared as u16 reg_cache[WM8900_MAXREG]; julia _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
