[dpdk-dev] [PATCH v5 1/4] examples/multi_process/client_server_mp: check port validity
Stephen Hemminger
stephen at networkplumber.org
Mon Aug 5 18:00:54 CEST 2019
On Sun, 4 Aug 2019 08:31:54 +0000
Matan Azrad <matan at mellanox.com> wrote:
> > > > /* convert parameter to a number and verify */
> > > > pm = strtoul(portmask, &end, 16);
> > > > - if (end == NULL || *end != '\0' || pm == 0)
> > > > + if (end == NULL || *end != '\0' || pm > UINT16_MAX || pm == 0)
> > >
> > > Why pm > UINT16_MAX ? should be something like > (1 <<
> > RTE_MAX_ETHPORTS) - 1.
> > > And need to be sure pm type can hold RTE_MAX_ETHPORTS bits,
> > otherwise port 0 may unlikely be all the time visible in the loop below.
> > >
> >
> > The DPDK assumes a lot of places that unsigned long will hold a port mask.
>
> So, all are bugs, no?
I don't think 32 bit build is that well tested. But yes a mask
needs to hold 64 ports.
> > If some extra bits are set, the error is visible later when the bits are leftover
> > after finding ports.
>
> Yes, but if there is a valid port which its port id is bigger than the portmask bits number - port 0 will be all the time visible in the check -> bug.
>
> > The original code had worse problems, it would not catch invalid pm values at
> > all and truncate silently.
>
> Yes, maybe, but I really don't understand why you chose to limit for 16 ports, where this number come from?
> So, my approach here, 2 options:
The problem here was my mistake for not having wide enough portmask.
More information about the dev
mailing list