| Message ID | 1429302240-654-2-git-send-email-jtoppins@cumulusnetworks.com |
|---|---|
| State | Changes Requested |
| Delegated to: | Jeff Kirsher |
| Headers | show |
> From: netdev-owner@vger.kernel.org [mailto:netdev-owner@vger.kernel.org] > On Behalf Of Jonathan Toppins > Sent: Friday, April 17, 2015 1:24 PM > To: Kirsher, Jeffrey T > Cc: Brandeburg, Jesse; Nelson, Shannon; Wyborny, Carolyn; Skidmore, Donald > C; Vick, Matthew; Ronciak, John; Williams, Mitch A; intel-wired- > lan@lists.osuosl.org; netdev@vger.kernel.org; gospo@cumulusnetworks.com; > shm@cumulusnetworks.com; Alan Liebthal > Subject: [PATCH v1 net-next 2/2] igb: support SIOCSMIIREG > > From: Alan Liebthal <alanl@cumulusnetworks.com> > > Support setting the MII register via SIOCSMIIREG. > > Signed-off-by: Alan Liebthal <alanl@cumulusnetworks.com> > Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com> > --- > drivers/net/ethernet/intel/igb/igb_main.c | 5 +++++ > 1 file changed, 5 insertions(+) Tested-by: Aaron Brown <aaron.f.brown@intel.com>
On 5/5/15 1:25 PM, Brown, Aaron F wrote: >> From: netdev-owner@vger.kernel.org [mailto:netdev-owner@vger.kernel.org] >> On Behalf Of Jonathan Toppins >> Sent: Friday, April 17, 2015 1:24 PM >> To: Kirsher, Jeffrey T >> Cc: Brandeburg, Jesse; Nelson, Shannon; Wyborny, Carolyn; Skidmore, Donald >> C; Vick, Matthew; Ronciak, John; Williams, Mitch A; intel-wired- >> lan@lists.osuosl.org; netdev@vger.kernel.org; gospo@cumulusnetworks.com; >> shm@cumulusnetworks.com; Alan Liebthal >> Subject: [PATCH v1 net-next 2/2] igb: support SIOCSMIIREG >> >> From: Alan Liebthal <alanl@cumulusnetworks.com> >> >> Support setting the MII register via SIOCSMIIREG. >> >> Signed-off-by: Alan Liebthal <alanl@cumulusnetworks.com> >> Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com> >> --- >> drivers/net/ethernet/intel/igb/igb_main.c | 5 +++++ >> 1 file changed, 5 insertions(+) > > Tested-by: Aaron Brown <aaron.f.brown@intel.com> > Thanks Aaron, appreciate the testing.
On 04/17/2015 01:24 PM, Jonathan Toppins wrote: > From: Alan Liebthal <alanl@cumulusnetworks.com> > > Support setting the MII register via SIOCSMIIREG. > > Signed-off-by: Alan Liebthal <alanl@cumulusnetworks.com> > Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com> > --- > drivers/net/ethernet/intel/igb/igb_main.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c > index 720b785..1071a71 100644 > --- a/drivers/net/ethernet/intel/igb/igb_main.c > +++ b/drivers/net/ethernet/intel/igb/igb_main.c > @@ -7141,6 +7141,11 @@ static int igb_mii_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd) > return -EIO; > break; > case SIOCSMIIREG: > + adapter->hw.phy.addr = data->phy_id; > + if (igb_write_phy_reg(&adapter->hw, data->reg_num & 0x1F, > + data->val_in)) > + return -EIO; > + break; > default: > return -EOPNOTSUPP; > } How and why is this being used? From what I can tell it looks like it is an easy way to break any of the existing interfaces if it is misused since all you would need to do is specify a phy address that doesn't match the existing PHY in the system and then you would likely lose link, or possibly mess up the configuration on the system requiring. I suspect this is a back door for some piece of user space code that is being given far more permission than it should be. - Alex
> On May 7, 2015, at 10:52 AM, Alexander Duyck <alexander.duyck@gmail.com> wrote: > >> diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c >> index 720b785..1071a71 100644 >> --- a/drivers/net/ethernet/intel/igb/igb_main.c >> +++ b/drivers/net/ethernet/intel/igb/igb_main.c >> @@ -7141,6 +7141,11 @@ static int igb_mii_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd) >> return -EIO; >> break; >> case SIOCSMIIREG: >> + adapter->hw.phy.addr = data->phy_id; >> + if (igb_write_phy_reg(&adapter->hw, data->reg_num & 0x1F, >> + data->val_in)) >> + return -EIO; >> + break; >> default: >> return -EOPNOTSUPP; >> } > > How and why is this being used? From what I can tell it looks like it is an easy way to break any of the existing interfaces if it is misused since all you would need to do is specify a phy address that doesn't match the existing PHY in the system and then you would likely lose link, or possibly mess up the configuration on the system requiring. > > I suspect this is a back door for some piece of user space code that is being given far more permission than it should be. I don't know about a back door, but the real problem is that it has a side-effect of changing the saved value of the phy addr. That is clearly a problem and can't be allowed. For the phylib stuff to really work as intended, the igb_write_phy_reg really should take the phy address as a parameter instead of getting the value from the structure itself. Or a new function should be defined that has that interface. -- Mark Rustad, Networking Division, Intel Corporation
On 5/7/15 4:46 PM, Rustad, Mark D wrote: >> On May 7, 2015, at 10:52 AM, Alexander Duyck <alexander.duyck@gmail.com> wrote: >> >>> diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c >>> index 720b785..1071a71 100644 >>> --- a/drivers/net/ethernet/intel/igb/igb_main.c >>> +++ b/drivers/net/ethernet/intel/igb/igb_main.c >>> @@ -7141,6 +7141,11 @@ static int igb_mii_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd) >>> return -EIO; >>> break; >>> case SIOCSMIIREG: >>> + adapter->hw.phy.addr = data->phy_id; >>> + if (igb_write_phy_reg(&adapter->hw, data->reg_num & 0x1F, >>> + data->val_in)) >>> + return -EIO; >>> + break; >>> default: >>> return -EOPNOTSUPP; >>> } >> >> How and why is this being used? From what I can tell it looks like it is an easy way to break any of the existing interfaces if it is misused since all you would need to do is specify a phy address that doesn't match the existing PHY in the system and then you would likely lose link, or possibly mess up the configuration on the system requiring. >> >> I suspect this is a back door for some piece of user space code that is being given far more permission than it should be. > > I don't know about a back door, but the real problem is that it has a > side-effect of changing the saved value of the phy addr. That is clearly > a problem and can't be allowed. This patch was worse before... it had changes in SIOGMIIREG that had similar side-effects, missed this one. Checking with some of the platform people here this patch can be dropped. We don't use it as a backdoor of any kind it was mainly used for debugging/guess-what-the-phy-addr-was when we originally got the boards. > > For the phylib stuff to really work as intended, the igb_write_phy_reg > really should take the phy address as a parameter instead of getting > the value from the structure itself. Or a new function should be > defined that has that interface. > > -- > Mark Rustad, Networking Division, Intel Corporation >
diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 720b785..1071a71 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -7141,6 +7141,11 @@ static int igb_mii_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd) return -EIO; break; case SIOCSMIIREG: + adapter->hw.phy.addr = data->phy_id; + if (igb_write_phy_reg(&adapter->hw, data->reg_num & 0x1F, + data->val_in)) + return -EIO; + break; default: return -EOPNOTSUPP; }