From 4683f42fde3977bdb4e8a09622788cc8b5313778 Mon Sep 17 00:00:00 2001 From: Mathias Krause Date: Sun, 7 Apr 2013 01:51:49 +0000 Subject: [PATCH] Bluetooth: fix possible info leak in bt_sock_recvmsg() In case the socket is already shutting down, bt_sock_recvmsg() returns with 0 without updating msg_namelen leading to net/socket.c leaking the local, uninitialized sockaddr_storage variable to userland -- 128 bytes of kernel stack memory. Fix this by moving the msg_namelen assignment in front of the shutdown test. Cc: Marcel Holtmann Cc: Gustavo Padovan Cc: Johan Hedberg Signed-off-by: Mathias Krause Signed-off-by: David S. Miller --- net/bluetooth/af_bluetooth.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c index d3ee69b35a78..0d1b08cc76e1 100644 --- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -230,6 +230,8 @@ int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock, if (flags & (MSG_OOB)) return -EOPNOTSUPP; + msg->msg_namelen = 0; + skb = skb_recv_datagram(sk, flags, noblock, &err); if (!skb) { if (sk->sk_shutdown & RCV_SHUTDOWN) @@ -237,8 +239,6 @@ int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock, return err; } - msg->msg_namelen = 0; - copied = skb->len; if (len < copied) { msg->msg_flags |= MSG_TRUNC; -- 2.39.5