RE: [EXT] Re: [PATCH v2 RESEND 1/1] net: fec: add xdp and page pool statistics

[Shenwei Wang]

> -----Original Message-----
> From: Paolo Abeni <pabeni@xxxxxxxxxx>
> Sent: Thursday, November 10, 2022 5:54 AM
> To: Shenwei Wang <shenwei.wang@xxxxxxx>; David S. Miller
> <davem@xxxxxxxxxxxxx>; Eric Dumazet <edumazet@xxxxxxxxxx>; Jakub
> Kicinski <kuba@xxxxxxxxxx>
> >       case ETH_SS_STATS:
> > -             for (i = 0; i < ARRAY_SIZE(fec_stats); i++)
> > -                     memcpy(data + i * ETH_GSTRING_LEN,
> > -                             fec_stats[i].name, ETH_GSTRING_LEN);
> > +             for (i = 0; i < ARRAY_SIZE(fec_stats); i++) {
> > +                     memcpy(data, fec_stats[i].name, ETH_GSTRING_LEN);
> > +                     data += ETH_GSTRING_LEN;
> > +             }
> > +             for (i = 0; i < ARRAY_SIZE(fec_xdp_stat_strs); i++) {
> > +                     memcpy(data, fec_xdp_stat_strs[i], ETH_GSTRING_LEN);
> > +                     data += ETH_GSTRING_LEN;
> 
> The above triggers a warning:
> 
> In function ‘fortify_memcpy_chk’,
>     inlined from ‘fec_enet_get_strings’
> at ../drivers/net/ethernet/freescale/fec_main.c:2788:4:
> ../include/linux/fortify-string.h:413:25: warning: call to ‘__read_overflow2_field’
> declared with attribute warning: detected read beyond size of field (2nd
> parameter); maybe use struct_group()? [-Wattribute-warning]
>   413 |                         __read_overflow2_field(q_size_field, size);
>       |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> I think you can address it changing fec_xdp_stat_strs definition to:
> 
> static const char fec_xdp_stat_strs[XDP_STATS_TOTAL][ETH_GSTRING_LEN] =

That does a problem. How about just change the memcpy to strncpy? 

Regards,
Shenwei

> { // ...
> 
> Cheers,
> 
> Paolo