drivers/net/eql.c: prevent reading uninitialized stack memory

commit 44467187dc22fdd33a1a06ea0ba86ce20be3fe3c upstream.

Fixed formatting (tabs and line breaks).

The EQL_GETMASTRCFG device ioctl allows unprivileged users to read 16
bytes of uninitialized stack memory, because the "master_name" member of
the master_config_t struct declared on the stack in eql_g_master_cfg()
is not altered or zeroed before being copied back to the user.  This
patch takes care of it.

Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/net/eql.c b/drivers/net/eql.c
index f5b96cadeb2544994c4aadeeb45f30113c082116..fd57fb421e912af88a39a54f253b4007e7e66079 100644 (file)
--- a/drivers/net/eql.c
+++ b/drivers/net/eql.c
@@ -554,6 +554,8 @@ static int eql_g_master_cfg(struct net_device *dev, master_config_t __user *mcp)
        equalizer_t *eql;
        master_config_t mc;
 
+       memset(&mc, 0, sizeof(master_config_t));
+
        if (eql_is_master(dev)) {
                eql = netdev_priv(dev);
                mc.max_slaves = eql->max_slaves;