Bluetooth: l2cap: fix 1 byte infoleak to userspace

Structure l2cap_options has one padding byte between max_tx and
txwin_size fields.  This byte in "opts" is copied to userspace
uninitialized.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index adf41692daf3..21f5385ca24d 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -392,6 +392,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, char __us
 
         switch (optname) {
         case L2CAP_OPTIONS:
+                memset(&opts, 0, sizeof(opts));
                 opts.imtu     = l2cap_pi(sk)->imtu;
                 opts.omtu     = l2cap_pi(sk)->omtu;
                 opts.flush_to = l2cap_pi(sk)->flush_to;