Re: [PATCH] ethdev: check for invalid device name

[Stephen Hemminger <stephen@networkplumber.org>]

On Wed, 13 Mar 2019 12:52:50 +0000
"Zhang, Qi Z" <qi.z.zhang@intel.com> wrote:

> HI
> 
> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Stephen Hemminger
> > Sent: Tuesday, March 12, 2019 2:16 AM
> > To: dev@dpdk.org
> > Cc: Stephen Hemminger <stephen@networkplumber.org>
> > Subject: [dpdk-dev] [PATCH] ethdev: check for invalid device name
> > 
> > Do not allow creating a ethernet device with a name over the allowed maximum
> > (or zero length). This is safer than silently truncating which is what happens now.
> > 
> > Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> > Acked-by: Andrew Rybchenko <arybchenko@solarflare.com>
> > ---
> > v1 - previously sent as RFC
> > 
> >  lib/librte_ethdev/rte_ethdev.c | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> > 
> > diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
> > index 85c1794968dd..0b81980ff71c 100644
> > --- a/lib/librte_ethdev/rte_ethdev.c
> > +++ b/lib/librte_ethdev/rte_ethdev.c
> > @@ -439,6 +439,16 @@ rte_eth_dev_allocate(const char *name)
> >  	uint16_t port_id;
> >  	struct rte_eth_dev *eth_dev = NULL;
> > 
> > +	if (*name) {  
> 
> Is above check same as "strlen(name) == 0"?

Yes, but checking for first null byte is slightly quicker. Alternative would
be to call strnlen() once.