ethtool: EEPROM dump no longer works for tg3 and natsemi

In the ethtool user-space application, tg3 and natsemi over-ride the
default implementation of dump_eeprom(). In both tg3_dump_eeprom() and
natsemi_dump_eeprom(), there is a magic number check which is not
present in the default implementation.

Commit b131dd5d ("[ETHTOOL]: Add support for large eeproms") snipped
the code which copied the ethtool_eeprom structure back to
user-space. tg3 and natsemi are over-writing the magic number field
and then checking it in user-space. With the ethtool_eeprom copy
removed, the check is failing.

The fix is simple. Add the ethtool_eeprom copy back.

Signed-off-by: Mandeep Singh Baines <msb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/net/core/ethtool.c b/net/core/ethtool.c
index a29b43d0b450..0133b5ebd545 100644
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -323,6 +323,11 @@ static int ethtool_get_eeprom(struct net_device *dev, void __user *useraddr)
                 bytes_remaining -= eeprom.len;
         }
 
+        eeprom.len = userbuf - (useraddr + sizeof(eeprom));
+        eeprom.offset -= eeprom.len;
+        if (copy_to_user(useraddr, &eeprom, sizeof(eeprom)))
+                ret = -EFAULT;
+
         kfree(data);
         return ret;
 }