Re: [PATCH linux-next] staging: ks7010: use strscpy() to instead of strncpy()

From: Dan Carpenter
Date: Thu Dec 29 2022 - 04:52:21 EST


On Thu, Dec 29, 2022 at 12:45:10PM +0300, Dan Carpenter wrote:
> On Mon, Dec 26, 2022 at 07:03:24PM +0800, yang.yang29@xxxxxxxxxx wrote:
> > From: Xu Panda <xu.panda@xxxxxxxxxx>
> >
> > The implementation of strscpy() is more robust and safer.
> > That's now the recommended way to copy NUL-terminated strings.
> >
> > Signed-off-by: Xu Panda <xu.panda@xxxxxxxxxx>
> > Signed-off-by: Yang Yang <yang.yang29@xxxxxxx>
> > ---
> > drivers/staging/ks7010/ks_wlan_net.c | 3 +--
> > 1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/staging/ks7010/ks_wlan_net.c b/drivers/staging/ks7010/ks_wlan_net.c
> > index 044c807ca022..e03c87f0bfe7 100644
> > --- a/drivers/staging/ks7010/ks_wlan_net.c
> > +++ b/drivers/staging/ks7010/ks_wlan_net.c
> > @@ -382,8 +382,7 @@ static int ks_wlan_get_nick(struct net_device *dev,
> > return -EPERM;
> >
> > /* for SLEEP MODE */
> > - strncpy(extra, priv->nick, 16);
> > - extra[16] = '\0';
> > + strscpy(extra, priv->nick, 17);
>
> I think this code is a buffer overflow. This is an implementation of
> SIOCGIWNICKN.

Huh... Maybe I'm wrong. I looked at a couple other implementations of
SIOCGIWNICKN and they all seem to assume a 17 character buffer...

Let me look deeper. I guess for now assume I am wrong.

regards,
dan carpenter