Hi, On Tue, Sep 10, 2024 at 2:37 AM Simon Horman <[email protected]> wrote: > > On Mon, Sep 09, 2024 at 04:39:28PM -0700, Justin Stitt wrote: > > strncpy() is deprecated for use on NUL-terminated destination strings [1] > > and > > as such we should prefer more robust and less ambiguous string interfaces. > > > > Towards the goal of [2], replace strncpy() with an alternative that > > guarantees NUL-termination and NUL-padding for the destination buffer. > > Hi Justin, > > I am curious to know why the _pad variant was chosen.
I chose the _pad variant as it matches the behavior of strncpy in this context, ensuring minimal functional change. I think the point you're trying to get at is that the net_device should be zero allocated to begin with -- rendering all thus NUL-padding superfluous. I have some questions out of curiosity: 1) do all control paths leading here zero-allocate the net_device struct? and 2) does it matter that this private data be NUL-padded (I assume not). With all that being said, I'd be happy to send a v2 using the regular strscpy variant if needed. > > > Link: > > https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings > > [1] > > Link: https://github.com/KSPP/linux/issues/90 [2] > > Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html > > Cc: Kees Cook <[email protected]> > > Cc: [email protected] > > Signed-off-by: Justin Stitt <[email protected]> > > --- > > Note: build-tested only. > > --- > > net/caif/chnl_net.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c > > index 47901bd4def1..ff37dceefa26 100644 > > --- a/net/caif/chnl_net.c > > +++ b/net/caif/chnl_net.c > > @@ -347,7 +347,7 @@ static int chnl_net_init(struct net_device *dev) > > struct chnl_net *priv; > > ASSERT_RTNL(); > > priv = netdev_priv(dev); > > - strncpy(priv->name, dev->name, sizeof(priv->name)); > > + strscpy_pad(priv->name, dev->name); > > INIT_LIST_HEAD(&priv->list_field); > > return 0; > > } > > > > --- > > base-commit: bc83b4d1f08695e85e85d36f7b803da58010161d > > change-id: 20240909-strncpy-net-caif-chnl_net-c-a505e955e697 > > > > Best regards, > > -- > > Justin Stitt <[email protected]> > > > > I appreciate the review. Thanks Justin
