On Fri, Aug 18, 2017 at 09:30:35AM +0000, David Laight wrote:
> From: Phil Sutter
> > Sent: 17 August 2017 18:10
> > The later check for 'k[0] != 0' requires a non-empty filter name,
> > otherwise NULL pointer dereference in 'q' might happen.
> >
> > Signed-off-by: Phil Sutter <p...@nwl.cc>
> > ---
> > tc/tc_filter.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/tc/tc_filter.c b/tc/tc_filter.c
> > index b13fb9185d4fd..a799edb35886d 100644
> > --- a/tc/tc_filter.c
> > +++ b/tc/tc_filter.c
> > @@ -412,6 +412,9 @@ static int tc_filter_get(int cmd, unsigned int flags,
> > int argc, char **argv)
> > usage();
> > return 0;
> > } else {
> > + if (!strlen(*argv))
> > + invarg("invalid filter name", *argv);
>
> That is nearly as bad as:
> p[strlen(p)] = 0;
Hey, it's not impossible! I could call tc like so:
| # tc filter get protocol ip prio 1 ""
What's funny about it is that the first call to matches() in
tc_filter_get() will catch the empty last parameter:
| # tc filter get prio 1 protocol ip ""
| Command line is not complete. Try option "help"
| # ./tc/tc filter get prio 1 protocol ip "" ""
| Error: duplicate "priority": "" is the second value.
Cheers, Phil
