net/igb/e1000/e1000e: more robust ethtool duplex/speed configuration

This makes sure that one cannot request a 99Mbps full-duplex and get a
100Mbps half-duplex configuration in return due to the way the
speed/duplex parameters are handled internally.

Tested: e1000 works
Signed-off-by: David Decotigny <decot@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 26 insertions, 20 deletions

diff --git a/drivers/net/e1000/e1000.h b/drivers/net/e1000/e1000.h
index a881dd0093b..b1b23ddd4ee 100644
--- a/drivers/net/e1000/e1000.h
+++ b/drivers/net/e1000/e1000.h
@@ -349,7 +349,7 @@ extern int e1000_up(struct e1000_adapter *adapter);
 extern void e1000_down(struct e1000_adapter *adapter);
 extern void e1000_reinit_locked(struct e1000_adapter *adapter);
 extern void e1000_reset(struct e1000_adapter *adapter);
-extern int e1000_set_spd_dplx(struct e1000_adapter *adapter, u16 spddplx);
+extern int e1000_set_spd_dplx(struct e1000_adapter *adapter, u32 spd, u8 dplx);
 extern int e1000_setup_all_rx_resources(struct e1000_adapter *adapter);
 extern int e1000_setup_all_tx_resources(struct e1000_adapter *adapter);
 extern void e1000_free_all_rx_resources(struct e1000_adapter *adapter);
diff --git a/drivers/net/e1000/e1000_ethtool.c b/drivers/net/e1000/e1000_ethtool.c
index 127fef4fce4..4fa727ce837 100644
--- a/drivers/net/e1000/e1000_ethtool.c
+++ b/drivers/net/e1000/e1000_ethtool.c
@@ -199,7 +199,7 @@ static int e1000_set_settings(struct net_device *netdev,
 		ecmd->advertising = hw->autoneg_advertised;
 	} else {
 		u32 speed = ethtool_cmd_speed(ecmd);
-		if (e1000_set_spd_dplx(adapter, speed + ecmd->duplex)) {
+		if (e1000_set_spd_dplx(adapter, speed, ecmd->duplex)) {
 			clear_bit(__E1000_RESETTING, &adapter->flags);
 			return -EINVAL;
 		}
diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index 477e066a1cf..c18cb8e883d 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -96,7 +96,6 @@ int e1000_up(struct e1000_adapter *adapter);
 void e1000_down(struct e1000_adapter *adapter);
 void e1000_reinit_locked(struct e1000_adapter *adapter);
 void e1000_reset(struct e1000_adapter *adapter);
-int e1000_set_spd_dplx(struct e1000_adapter *adapter, u16 spddplx);
 int e1000_setup_all_tx_resources(struct e1000_adapter *adapter);
 int e1000_setup_all_rx_resources(struct e1000_adapter *adapter);
 void e1000_free_all_tx_resources(struct e1000_adapter *adapter);
@@ -4385,7 +4384,6 @@ static int e1000_mii_ioctl(struct net_device *netdev, struct ifreq *ifr,
 	struct mii_ioctl_data *data = if_mii(ifr);
 	int retval;
 	u16 mii_reg;
-	u16 spddplx;
 	unsigned long flags;
 
 	if (hw->media_type != e1000_media_type_copper)
@@ -4424,17 +4422,18 @@ static int e1000_mii_ioctl(struct net_device *netdev, struct ifreq *ifr,
 					hw->autoneg = 1;
 					hw->autoneg_advertised = 0x2F;
 				} else {
+					u32 speed;
 					if (mii_reg & 0x40)
-						spddplx = SPEED_1000;
+						speed = SPEED_1000;
 					else if (mii_reg & 0x2000)
-						spddplx = SPEED_100;
+						speed = SPEED_100;
 					else
-						spddplx = SPEED_10;
-					spddplx += (mii_reg & 0x100)
-						   ? DUPLEX_FULL :
-						   DUPLEX_HALF;
-					retval = e1000_set_spd_dplx(adapter,
-								    spddplx);
+						speed = SPEED_10;
+					retval = e1000_set_spd_dplx(
+						adapter, speed,
+						((mii_reg & 0x100)
+						 ? DUPLEX_FULL :
+						 DUPLEX_HALF));
 					if (retval)
 						return retval;
 				}
@@ -4596,20 +4595,24 @@ static void e1000_restore_vlan(struct e1000_adapter *adapter)
 	}
 }
 
-int e1000_set_spd_dplx(struct e1000_adapter *adapter, u16 spddplx)
+int e1000_set_spd_dplx(struct e1000_adapter *adapter, u32 spd, u8 dplx)
 {
 	struct e1000_hw *hw = &adapter->hw;
 
 	hw->autoneg = 0;
 
+	/* Make sure dplx is at most 1 bit and lsb of speed is not set
+	 * for the switch() below to work */
+	if ((spd & 1) || (dplx & ~1))
+		goto err_inval;
+
 	/* Fiber NICs only allow 1000 gbps Full duplex */
 	if ((hw->media_type == e1000_media_type_fiber) &&
-		spddplx != (SPEED_1000 + DUPLEX_FULL)) {
-		e_err(probe, "Unsupported Speed/Duplex configuration\n");
-		return -EINVAL;
-	}
+	    spd != SPEED_1000 &&
+	    dplx != DUPLEX_FULL)
+		goto err_inval;
 
-	switch (spddplx) {
+	switch (spd + dplx) {
 	case SPEED_10 + DUPLEX_HALF:
 		hw->forced_speed_duplex = e1000_10_half;
 		break;
@@ -4628,10 +4631,13 @@ int e1000_set_spd_dplx(struct e1000_adapter *adapter, u16 spddplx)
 		break;
 	case SPEED_1000 + DUPLEX_HALF: /* not supported */
 	default:
-		e_err(probe, "Unsupported Speed/Duplex configuration\n");
-		return -EINVAL;
+		goto err_inval;
 	}
 	return 0;
+
+err_inval:
+	e_err(probe, "Unsupported Speed/Duplex configuration\n");
+	return -EINVAL;
 }
 
 static int __e1000_shutdown(struct pci_dev *pdev, bool *enable_wake)