| Message ID | 20240903171536.628930-1-niklas.soderlund+renesas@ragnatech.se (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
| Series | [net-next] net: phy: Check for read errors in SIOCGMIIREG | expand |
On 9/3/24 10:15, Niklas Söderlund wrote: > When reading registers from the PHY using the SIOCGMIIREG IOCTL any > errors returned from either mdiobus_read() or mdiobus_c45_read() are > ignored, and parts of the returned error is passed as the register value > back to user-space. > > For example, if mdiobus_c45_read() is used with a bus that do not > implement the read_c45() callback -EOPNOTSUPP is returned. This is > however directly stored in mii_data->val_out and returned as the > registers content. As val_out is a u16 the error code is truncated and > returned as a plausible register value. > > Fix this by first checking the return value for errors before returning > it as the register content. > > Before this patch, > > # phytool read eth0/0:1/0 > 0xffa1 > > After this change, > > $ phytool read eth0/0:1/0 > error: phy_read (-95) > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Thanks for fixing that!
On Tue, Sep 03, 2024 at 07:15:36PM +0200, Niklas Söderlund wrote: > When reading registers from the PHY using the SIOCGMIIREG IOCTL any > errors returned from either mdiobus_read() or mdiobus_c45_read() are > ignored, and parts of the returned error is passed as the register value > back to user-space. > > For example, if mdiobus_c45_read() is used with a bus that do not > implement the read_c45() callback -EOPNOTSUPP is returned. This is > however directly stored in mii_data->val_out and returned as the > registers content. As val_out is a u16 the error code is truncated and > returned as a plausible register value. > > Fix this by first checking the return value for errors before returning > it as the register content. > > Before this patch, > > # phytool read eth0/0:1/0 > 0xffa1 > > After this change, > > $ phytool read eth0/0:1/0 > error: phy_read (-95) > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> write is similarly broken, but i don't think we care about that. Thanks Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
Hello Niklas-san, > From: Niklas Söderlund, Sent: Wednesday, September 4, 2024 2:16 AM > > When reading registers from the PHY using the SIOCGMIIREG IOCTL any > errors returned from either mdiobus_read() or mdiobus_c45_read() are > ignored, and parts of the returned error is passed as the register value > back to user-space. > > For example, if mdiobus_c45_read() is used with a bus that do not > implement the read_c45() callback -EOPNOTSUPP is returned. This is > however directly stored in mii_data->val_out and returned as the > registers content. As val_out is a u16 the error code is truncated and > returned as a plausible register value. > > Fix this by first checking the return value for errors before returning > it as the register content. > > Before this patch, > > # phytool read eth0/0:1/0 > 0xffa1 > > After this change, > > $ phytool read eth0/0:1/0 > error: phy_read (-95) > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Thank you for the patch! Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> And, I tested on my environment (R-Car V4H with RTSN driver), and it works. So, Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Best regards, Yoshihiro Shimoda > --- > drivers/net/phy/phy.c | 17 +++++++++++------ > 1 file changed, 11 insertions(+), 6 deletions(-) > > diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c > index cba3af926429..4f3e742907cb 100644 > --- a/drivers/net/phy/phy.c > +++ b/drivers/net/phy/phy.c > @@ -342,14 +342,19 @@ int phy_mii_ioctl(struct phy_device *phydev, struct ifreq *ifr, int cmd) > if (mdio_phy_id_is_c45(mii_data->phy_id)) { > prtad = mdio_phy_id_prtad(mii_data->phy_id); > devad = mdio_phy_id_devad(mii_data->phy_id); > - mii_data->val_out = mdiobus_c45_read( > - phydev->mdio.bus, prtad, devad, > - mii_data->reg_num); > + ret = mdiobus_c45_read(phydev->mdio.bus, prtad, devad, > + mii_data->reg_num); > + > } else { > - mii_data->val_out = mdiobus_read( > - phydev->mdio.bus, mii_data->phy_id, > - mii_data->reg_num); > + ret = mdiobus_read(phydev->mdio.bus, mii_data->phy_id, > + mii_data->reg_num); > } > + > + if (ret < 0) > + return ret; > + > + mii_data->val_out = ret; > + > return 0; > > case SIOCSMIIREG: > -- > 2.46.0 >
On Tue, Sep 3, 2024 at 7:16 PM Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> wrote: > When reading registers from the PHY using the SIOCGMIIREG IOCTL any > errors returned from either mdiobus_read() or mdiobus_c45_read() are > ignored, and parts of the returned error is passed as the register value > back to user-space. > > For example, if mdiobus_c45_read() is used with a bus that do not > implement the read_c45() callback -EOPNOTSUPP is returned. This is > however directly stored in mii_data->val_out and returned as the > registers content. As val_out is a u16 the error code is truncated and > returned as a plausible register value. > > Fix this by first checking the return value for errors before returning > it as the register content. > > Before this patch, > > # phytool read eth0/0:1/0 > 0xffa1 > > After this change, > > $ phytool read eth0/0:1/0 > error: phy_read (-95) > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Gr{oetje,eeting}s, Geert
Hello: This patch was applied to netdev/net-next.git (main) by Jakub Kicinski <kuba@kernel.org>: On Tue, 3 Sep 2024 19:15:36 +0200 you wrote: > When reading registers from the PHY using the SIOCGMIIREG IOCTL any > errors returned from either mdiobus_read() or mdiobus_c45_read() are > ignored, and parts of the returned error is passed as the register value > back to user-space. > > For example, if mdiobus_c45_read() is used with a bus that do not > implement the read_c45() callback -EOPNOTSUPP is returned. This is > however directly stored in mii_data->val_out and returned as the > registers content. As val_out is a u16 the error code is truncated and > returned as a plausible register value. > > [...] Here is the summary with links: - [net-next] net: phy: Check for read errors in SIOCGMIIREG https://git.kernel.org/netdev/net-next/c/569bf6d481b0 You are awesome, thank you!
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c index cba3af926429..4f3e742907cb 100644 --- a/drivers/net/phy/phy.c +++ b/drivers/net/phy/phy.c @@ -342,14 +342,19 @@ int phy_mii_ioctl(struct phy_device *phydev, struct ifreq *ifr, int cmd) if (mdio_phy_id_is_c45(mii_data->phy_id)) { prtad = mdio_phy_id_prtad(mii_data->phy_id); devad = mdio_phy_id_devad(mii_data->phy_id); - mii_data->val_out = mdiobus_c45_read( - phydev->mdio.bus, prtad, devad, - mii_data->reg_num); + ret = mdiobus_c45_read(phydev->mdio.bus, prtad, devad, + mii_data->reg_num); + } else { - mii_data->val_out = mdiobus_read( - phydev->mdio.bus, mii_data->phy_id, - mii_data->reg_num); + ret = mdiobus_read(phydev->mdio.bus, mii_data->phy_id, + mii_data->reg_num); } + + if (ret < 0) + return ret; + + mii_data->val_out = ret; + return 0; case SIOCSMIIREG:
When reading registers from the PHY using the SIOCGMIIREG IOCTL any errors returned from either mdiobus_read() or mdiobus_c45_read() are ignored, and parts of the returned error is passed as the register value back to user-space. For example, if mdiobus_c45_read() is used with a bus that do not implement the read_c45() callback -EOPNOTSUPP is returned. This is however directly stored in mii_data->val_out and returned as the registers content. As val_out is a u16 the error code is truncated and returned as a plausible register value. Fix this by first checking the return value for errors before returning it as the register content. Before this patch, # phytool read eth0/0:1/0 0xffa1 After this change, $ phytool read eth0/0:1/0 error: phy_read (-95) Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> --- drivers/net/phy/phy.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-)