From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat, 13 May 2017 22:31:26 +0000 (-0400)
Subject: ethtool: don't open-code memdup_user()
X-Git-Tag: v4.13-rc1~151^2~2
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=30e7e3ecf39e578ffab6d5944c79c1d30dee0d3f;p=karo-tx-linux.git

ethtool: don't open-code memdup_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 03111a2d6653..674b6c9cec18 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -2322,16 +2322,12 @@ static int ethtool_set_tunable(struct net_device *dev, void __user *useraddr)
 	ret = ethtool_tunable_valid(&tuna);
 	if (ret)
 		return ret;
-	data = kmalloc(tuna.len, GFP_USER);
-	if (!data)
-		return -ENOMEM;
 	useraddr += sizeof(tuna);
-	ret = -EFAULT;
-	if (copy_from_user(data, useraddr, tuna.len))
-		goto out;
+	data = memdup_user(useraddr, tuna.len);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
 	ret = ops->set_tunable(dev, &tuna, data);
 
-out:
 	kfree(data);
 	return ret;
 }
@@ -2507,18 +2503,14 @@ static int set_phy_tunable(struct net_device *dev, void __user *useraddr)
 	ret = ethtool_phy_tunable_valid(&tuna);
 	if (ret)
 		return ret;
-	data = kmalloc(tuna.len, GFP_USER);
-	if (!data)
-		return -ENOMEM;
 	useraddr += sizeof(tuna);
-	ret = -EFAULT;
-	if (copy_from_user(data, useraddr, tuna.len))
-		goto out;
+	data = memdup_user(useraddr, tuna.len);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
 	mutex_lock(&phydev->lock);
 	ret = phydev->drv->set_tunable(phydev, &tuna, data);
 	mutex_unlock(&phydev->lock);
 
-out:
 	kfree(data);
 	return ret;
 }