Merge 17c66e9e49a181498ae3c75809c98fdbe630de28 on remote branch

Change-Id: I49238aefe09bba152a8000c046959157c328f183

1 files changed, 14 insertions, 3 deletions

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index 9a53c66deb64..66428c0eb663 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -428,8 +428,13 @@ static noinline_for_stack int ethtool_get_drvinfo(struct net_device *dev,
 		if (rc >= 0)
 			info.n_priv_flags = rc;
 	}
-	if (ops->get_regs_len)
-		info.regdump_len = ops->get_regs_len(dev);
+	if (ops->get_regs_len) {
+		int ret = ops->get_regs_len(dev);
+
+		if (ret > 0)
+			info.regdump_len = ret;
+	}
+
 	if (ops->get_eeprom_len)
 		info.eedump_len = ops->get_eeprom_len(dev);
 
@@ -883,6 +888,9 @@ static int ethtool_get_regs(struct net_device *dev, char __user *useraddr)
 		return -EFAULT;
 
 	reglen = ops->get_regs_len(dev);
+	if (reglen <= 0)
+		return reglen;
+
 	if (regs.len > reglen)
 		regs.len = reglen;
 
@@ -893,13 +901,16 @@ static int ethtool_get_regs(struct net_device *dev, char __user *useraddr)
 			return -ENOMEM;
 	}
 
+	if (regs.len < reglen)
+		reglen = regs.len;
+
 	ops->get_regs(dev, &regs, regbuf);
 
 	ret = -EFAULT;
 	if (copy_to_user(useraddr, &regs, sizeof(regs)))
 		goto out;
 	useraddr += offsetof(struct ethtool_regs, data);
-	if (regbuf && copy_to_user(useraddr, regbuf, regs.len))
+	if (copy_to_user(useraddr, regbuf, reglen))
 		goto out;
 	ret = 0;