Merge branch 'ethtool-link_mode'

Danielle Ratson says:

====================
Fix link_mode derived params functionality

Currently, link_mode parameter derives 3 other link parameters, speed,
lanes and duplex, and the derived information is sent to user space.

Few bugs were found in that functionality.
First, some drivers clear the 'ethtool_link_ksettings' struct in their
get_link_ksettings() callback and cause receiving wrong link mode
information in user space. And also, some drivers can report random
values in the 'link_mode' field and cause general protection fault.

Second, the link parameters are only derived in netlink path so in ioctl
path, we don't any reasonable values.

Third, setting 'speed 10000 lanes 1' fails since the lanes parameter
wasn't set for ETHTOOL_LINK_MODE_10000baseR_FEC_BIT.

Patch #1 solves the first two problems by removing link_mode parameter
and deriving the link parameters in driver instead of ethtool.
Patch #2 solves the third one, by setting the lanes parameter for the
link_mode.

v3:
	* Remove the link_mode parameter in the first patch to solve
	  both two issues from patch#1 and patch#2.
	* Add the second patch to solve the third issue.

v2:
	* Add patch #2.
	* Introduce 'cap_link_mode_supported' instead of adding a
	  validity field to 'ethtool_link_ksettings' struct in patch #1.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 18 insertions, 17 deletions

diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index c6a383dfd6c2..f9dcbad84788 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -273,6 +273,7 @@ const struct link_mode_info link_mode_params[] = {
 	__DEFINE_LINK_MODE_PARAMS(10000, KR, Full),
 	[ETHTOOL_LINK_MODE_10000baseR_FEC_BIT] = {
 		.speed	= SPEED_10000,
+		.lanes	= 1,
 		.duplex = DUPLEX_FULL,
 	},
 	__DEFINE_LINK_MODE_PARAMS(20000, MLD2, Full),
@@ -562,3 +563,19 @@ void ethtool_set_ethtool_phy_ops(const struct ethtool_phy_ops *ops)
 	rtnl_unlock();
 }
 EXPORT_SYMBOL_GPL(ethtool_set_ethtool_phy_ops);
+
+void
+ethtool_params_from_link_mode(struct ethtool_link_ksettings *link_ksettings,
+			      enum ethtool_link_mode_bit_indices link_mode)
+{
+	const struct link_mode_info *link_info;
+
+	if (WARN_ON_ONCE(link_mode >= __ETHTOOL_LINK_MODE_MASK_NBITS))
+		return;
+
+	link_info = &link_mode_params[link_mode];
+	link_ksettings->base.speed = link_info->speed;
+	link_ksettings->lanes = link_info->lanes;
+	link_ksettings->base.duplex = link_info->duplex;
+}
+EXPORT_SYMBOL_GPL(ethtool_params_from_link_mode);
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 24783b71c584..771688e1b0da 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -426,29 +426,13 @@ struct ethtool_link_usettings {
 int __ethtool_get_link_ksettings(struct net_device *dev,
 				 struct ethtool_link_ksettings *link_ksettings)
 {
-	const struct link_mode_info *link_info;
-	int err;
-
 	ASSERT_RTNL();
 
 	if (!dev->ethtool_ops->get_link_ksettings)
 		return -EOPNOTSUPP;
 
 	memset(link_ksettings, 0, sizeof(*link_ksettings));
-
-	link_ksettings->link_mode = -1;
-	err = dev->ethtool_ops->get_link_ksettings(dev, link_ksettings);
-	if (err)
-		return err;
-
-	if (link_ksettings->link_mode != -1) {
-		link_info = &link_mode_params[link_ksettings->link_mode];
-		link_ksettings->base.speed = link_info->speed;
-		link_ksettings->lanes = link_info->lanes;
-		link_ksettings->base.duplex = link_info->duplex;
-	}
-
-	return 0;
+	return dev->ethtool_ops->get_link_ksettings(dev, link_ksettings);
 }
 EXPORT_SYMBOL(__ethtool_get_link_ksettings);