Re: [PATCH] net: phy: tja11xx: replace deprecated strncpy with ethtool_sprintf

From: Andrew Lunn <andrew@lunn.ch>
To: Justin Stitt <justinstitt@google.com>
Cc: Heiner Kallweit <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH] net: phy: tja11xx: replace deprecated strncpy with ethtool_sprintf
Date: Fri, 13 Oct 2023 22:12:56 +0200	[thread overview]
Message-ID: <0c401bcb-70a8-47a5-bca0-0b9e8e0439a8@lunn.ch> (raw)
In-Reply-To: <CAFhGd8pmq3UKBE_6ZbLyvRRhXJzaWMQ2GfosvcEEeAS-n7M4aQ@mail.gmail.com>

On Fri, Oct 13, 2023 at 12:53:53PM -0700, Justin Stitt wrote:
> On Fri, Oct 13, 2023 at 5:22 AM Andrew Lunn <andrew@lunn.ch> wrote:
> >
> > > -     for (i = 0; i < ARRAY_SIZE(tja11xx_hw_stats); i++) {
> > > -             strncpy(data + i * ETH_GSTRING_LEN,
> > > -                     tja11xx_hw_stats[i].string, ETH_GSTRING_LEN);
> > > -     }
> > > +     for (i = 0; i < ARRAY_SIZE(tja11xx_hw_stats); i++)
> > > +             ethtool_sprintf(&data, "%s", tja11xx_hw_stats[i].string);
> > >  }
> >
> > I assume you are using "%s" because tja11xx_hw_stats[i].string cannot
> > be trusted as a format string? Is this indicating we need an
> > ethtool_puts() ?
> 
> Indeed, it would trigger a -Wformat-security warning.
> 
> An ethtool_puts() would be useful for this situation.

Hi Justin

hyperv/netvsc_drv.c:			ethtool_sprintf(&p, netvsc_stats[i].name);
hyperv/netvsc_drv.c:			ethtool_sprintf(&p, vf_stats[i].name);
ethernet/intel/i40e/i40e_ethtool.c:		ethtool_sprintf(&p, i40e_gstrings_priv_flags[i].flag_string);
ethernet/intel/i40e/i40e_ethtool.c:		ethtool_sprintf(&p, i40e_gl_gstrings_priv_flags[i].flag_string);
ethernet/intel/ice/ice_ethtool.c:			ethtool_sprintf(&p, ice_gstrings_priv_flags[i].name);
ethernet/intel/igc/igc_ethtool.c:			ethtool_sprintf(&p, igc_gstrings_stats[i].stat_string);
ethernet/intel/ixgbe/ixgbe_ethtool.c:			ethtool_sprintf(&p, ixgbe_gstrings_test[i]);
ethernet/netronome/nfp/nfp_net_ethtool.c:			ethtool_sprintf(&data, nfp_self_test[i].name);
ethernet/netronome/nfp/nfp_net_ethtool.c:		ethtool_sprintf(&data, nfp_net_et_stats[i + swap_off].name);
ethernet/netronome/nfp/nfp_net_ethtool.c:		ethtool_sprintf(&data, nfp_net_et_stats[i - swap_off].name);
ethernet/netronome/nfp/nfp_net_ethtool.c:		ethtool_sprintf(&data, nfp_net_et_stats[i].name);
ethernet/fungible/funeth/funeth_ethtool.c:			ethtool_sprintf(&p, txq_stat_names[j]);
ethernet/fungible/funeth/funeth_ethtool.c:			ethtool_sprintf(&p, xdpq_stat_names[j]);
ethernet/fungible/funeth/funeth_ethtool.c:			ethtool_sprintf(&p, rxq_stat_names[j]);
ethernet/fungible/funeth/funeth_ethtool.c:			ethtool_sprintf(&p, tls_stat_names[j]);
ethernet/amazon/ena/ena_ethtool.c:		ethtool_sprintf(&data, ena_stats->name);
ethernet/amazon/ena/ena_ethtool.c:			ethtool_sprintf(&data, ena_stats->name);
ethernet/brocade/bna/bnad_ethtool.c:		ethtool_sprintf(&string, bnad_net_stats_strings[i]);
ethernet/pensando/ionic/ionic_stats.c:		ethtool_sprintf(buf, ionic_lif_stats_desc[i].name);
ethernet/pensando/ionic/ionic_stats.c:		ethtool_sprintf(buf, ionic_port_stats_desc[i].name);
ethernet/hisilicon/hns/hns_dsaf_gmac.c:		ethtool_sprintf(&buff, g_gmac_stats_string[i].desc);
ethernet/hisilicon/hns/hns_dsaf_xgmac.c:		ethtool_sprintf(&buff, g_xgmac_stats_string[i].desc);
vmxnet3/vmxnet3_ethtool.c:			ethtool_sprintf(&buf, vmxnet3_tq_dev_stats[i].desc);
vmxnet3/vmxnet3_ethtool.c:			ethtool_sprintf(&buf, vmxnet3_tq_driver_stats[i].desc);
vmxnet3/vmxnet3_ethtool.c:			ethtool_sprintf(&buf, vmxnet3_rq_dev_stats[i].desc);
vmxnet3/vmxnet3_ethtool.c:			ethtool_sprintf(&buf, vmxnet3_rq_driver_stats[i].desc);
vmxnet3/vmxnet3_ethtool.c:		ethtool_sprintf(&buf, vmxnet3_global_stats[i].desc);

It looks like there are enough potential users to justify adding
it. Do you have the time and patience?

    Andrew