[20/80] drivers/net/eql.c: prevent reading uninitialized stack memory

Greg KH
2010-09-24T16:58:13Z

From: Dan Rosenberg <drosenberg@vsecurity.com>

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>

---
drivers/net/eql.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/net/eql.c
+++ b/drivers/net/eql.c
@@ -555,6 +555,8 @@ static int eql_g_master_cfg(struct net_d
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;