[dpdk-dev] [PATCH] lib/cmdline: init parse result memeory

[Xueming(Steven) Li]

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Xueming(Steven) Li
> Sent: Thursday, December 7, 2017 11:05 PM
> To: Olivier MATZ <olivier.matz at 6wind.com>
> Cc: dev at dpdk.org
> Subject: Re: [dpdk-dev] [PATCH] lib/cmdline: init parse result memeory
> 
> Hi Olivier,
> 
> > -----Original Message-----
> > From: Olivier MATZ [mailto:olivier.matz at 6wind.com]
> > Sent: Thursday, December 7, 2017 10:48 PM
> > To: Xueming(Steven) Li <xuemingl at mellanox.com>
> > Cc: dev at dpdk.org
> > Subject: Re: [PATCH] lib/cmdline: init parse result memeory
> >
> > On Wed, Nov 15, 2017 at 11:54:02PM +0800, Xueming Li wrote:
> > > Initialize binary result memory before parsing to avoid garbage in
> > > parsing result.
> > >
> > > Signed-off-by: Xueming Li <xuemingl at mellanox.com>
> > > ---
> > >  lib/librte_cmdline/cmdline_parse.c | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/lib/librte_cmdline/cmdline_parse.c
> > > b/lib/librte_cmdline/cmdline_parse.c
> > > index 3e12ee54f..9124758f1 100644
> > > --- a/lib/librte_cmdline/cmdline_parse.c
> > > +++ b/lib/librte_cmdline/cmdline_parse.c
> > > @@ -267,6 +267,8 @@ cmdline_parse(struct cmdline *cl, const char * buf)
> > >  	if (!cl || !buf)
> > >  		return CMDLINE_PARSE_BAD_ARGS;
> > >
> > > +	memset(tmp_result.buf, 0, sizeof(tmp_result.buf));
> > > +
> > >  	ctx = cl->ctx;
> > >
> > >  	/*
> >
> >
> > Did you see an issue (a bug or a crash) without the memset()?
> > Or is it to avoid filling unused fields in the parsed struct?
> Yes, I'm using same struct for some similar commands, have to avoid
> filling unused fields.
> 
> >
> > I'm not sure if your patch is enough: cmdline_parse() calls
> > match_inst() for each registered command. If a command partially
> > matches (only the first tokens), the buffer is modified. So the next
> > one will start with a dirty buffer.
> >
> > I suggest to put the memset() in match_inst() instead. Something like
> this:
> >
> > 	if (resbuf != NULL)
> > 		memset(resbuf, 0, resbuf_size);
> >
> >
> > It will reset the buffer before using it.
> It was there for performance concern, since the buffer could be tainted,
> I'll upload a new version according to your suggestion, appreciate your
> suggestion.
Rte_flow CLI seems to be relying on modified buffer, add Adrien:
testpmd> flow create 0 ingress pattern eth  / ipv4 / udp / vxlan / end actions rss queues 1 2 end level 1 / mark id 0x123456  / end
Caught error type 2 (flow rule (handle)): no valid action

> 
> >
> > Olivier