Re: [PATCH] brcmfmac: fix a loop exit condition

Dan Carpenter
2021-05-08T11:03:08Z

On Fri, Apr 23, 2021 at 02:20:35PM +0200, Christophe JAILLET wrote:
> Le 23/04/2021 à 14:11, Dan Carpenter a écrit :
> > On Fri, Apr 23, 2021 at 01:59:36PM +0200, Johannes Berg wrote:
> > > On Fri, 2021-04-23 at 14:46 +0300, Dan Carpenter wrote:
> > > > This code is supposed to loop over the whole board_type[] string. The
> > > > current code kind of works just because ascii values start 97 and the
> > > > string is likely shorter than that so it will break when we hit the NUL
> > > > terminator. But really the condition should be "i < len" instead of
> > > > "i < board_type[i]".
> > > >
> > > > Fixes: 29e354ebeeec ("brcmfmac: Transform compatible string for FW loading")
> > > > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> > > > ---
> > > >  drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c | 2 +-
> > > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> > > > index a7554265f95f..9b75e396fc50 100644
> > > > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> > > > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> > > > @@ -34,7 +34,7 @@ void brcmf_of_probe(struct device *dev, enum brcmf_bus_type bus_type,
> > > >   len = strlen(tmp) + 1;
> > > >   board_type = devm_kzalloc(dev, len, GFP_KERNEL);
> > > >   strscpy(board_type, tmp, len);
> > > > - for (i = 0; i < board_type[i]; i++) {
> > > > + for (i = 0; i < len; i++) {
> > > >   if (board_type[i] == '/')
> > > >   board_type[i] = '-';
> > > >   }
> > >
> > > It should probably just use strreplace() though :)
> >
> > Good point. I'll send a v2.
> >
>
> and the 2 lines above look like a devm_kstrdup.
>
> The (unlikely) malloc failure test is also missing.

It turns out that Smatch checks for allocation failure were really
ancient and really crap... I need to add all devm_ functions.
Probably should re-write all that code.

Also originally GFP_NOFAIL was 0x800 and now it is 0x8000. Smatch
was out of sync. So the functions that were supposed to be checked
were all disabled... Need to figure out a better way to do that as
well.

regards,
dan carpenter