Bluetooth: sco: fix information leak to userspace

struct sco_conninfo has one padding byte in the end.  Local variable
cinfo of type sco_conninfo is copied to userspace with this uninizialized
one byte, leading to old stack contents leak.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index 960c6d1..926ed39 100644 (file)
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -703,6 +703,7 @@ static int sco_sock_getsockopt_old(struct socket *sock, int optname, char __user
                        break;
                }
 
+               memset(&cinfo, 0, sizeof(cinfo));
                cinfo.hci_handle = sco_pi(sk)->conn->hcon->handle;
                memcpy(cinfo.dev_class, sco_pi(sk)->conn->hcon->dev_class, 3);