Re: [dpdk-dev] [PATCH] app/testpmd: fix copying the name of the dynflag

[Ori Kam <orika@mellanox.com>]

Hi Bernard,

> -----Original Message-----
> From: Ori Kam
> Sent: Thursday, January 30, 2020 8:56 PM
> To: Iremonger, Bernard <bernard.iremonger@intel.com>; Lu, Wenzhuo
> <wenzhuo.lu@intel.com>; Wu, Jingjing <jingjing.wu@intel.com>
> Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yigit@intel.com>; Slava Ovsiienko
> <viacheslavo@mellanox.com>
> Subject: RE: [PATCH] app/testpmd: fix copying the name of the dynflag
> 
> Hi Bernard,
> 
> Thanks for review, PSB
> 
> Ori
> 
> > -----Original Message-----
> > From: Iremonger, Bernard <bernard.iremonger@intel.com>
> > Sent: Thursday, January 30, 2020 6:54 PM
> > To: Ori Kam <orika@mellanox.com>; Lu, Wenzhuo <wenzhuo.lu@intel.com>;
> > Wu, Jingjing <jingjing.wu@intel.com>
> > Cc: dev@dpdk.org; Yigit, Ferruh <ferruh.yigit@intel.com>; Slava Ovsiienko
> > <viacheslavo@mellanox.com>
> > Subject: RE: [PATCH] app/testpmd: fix copying the name of the dynflag
> >
> > Hi Ori,
> >
> > > -----Original Message-----
> > > From: Ori Kam <orika@mellanox.com>
> > > Sent: Thursday, January 30, 2020 1:23 PM
> > > To: Lu, Wenzhuo <wenzhuo.lu@intel.com>; Wu, Jingjing
> > > <jingjing.wu@intel.com>; Iremonger, Bernard
> > > <bernard.iremonger@intel.com>
> > > Cc: dev@dpdk.org; orika@mellanox.com; Yigit, Ferruh
> > > <ferruh.yigit@intel.com>; viacheslavo@mellanox.com
> > > Subject: [PATCH] app/testpmd: fix copying the name of the dynflag
> > >
> > > When working with testpmd and setting the dynflag name, we copy the
> > > name given by the cmd to the dynflag name.
> > >
> > > The issue is that the size of the dynflag name is smaller then the string used
> > > by testpmd.
> > >
> > > This commit solves this issue by usign strncpy.
> > >
> > > Coverity issue: 353610
> > >
> > > Fixes: b57b66a97ebf ("app/testpmd: support mbuf dynamic flag")
> > >
> > > Signed-off-by: Ori Kam <orika@mellanox.com>
> > > ---
> > >  app/test-pmd/cmdline.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c index
> > > dab22bc..09429f9 100644
> > > --- a/app/test-pmd/cmdline.c
> > > +++ b/app/test-pmd/cmdline.c
> > > @@ -18867,7 +18867,7 @@ struct cmd_config_tx_dynf_specific_result {
> > >  		return;
> > >  	flag = rte_mbuf_dynflag_lookup(res->name, NULL);
> > >  	if (flag <= 0) {
> > > -		strcpy(desc_flag.name, res->name);
> > > +		strncpy(desc_flag.name, res->name,
> > > sizeof(*desc_flag.name));
> >
> > This does not look correct to me.
> > Should it be sizeof(desc_flag.name[RTE_MBUF_DYN_NAMESIZE]));
> >
> 
> You are correct, I will send a new version.
> 
I wasn't  clear I will fix the code but the fix is not like you suggested.
Your fix also doesn't work the return size will be 1.
The solution is sizeof(desc_flag.name)

> > >  		desc_flag.flags = 0;
> > >  		flag = rte_mbuf_dynflag_register(&desc_flag);
> > >  		if (flag < 0) {
> > > --
> > > 1.8.3.1
> >
> > Regards,
> >
> > Bernard.