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 <marcel@holtmann.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Mathias Krause 2013-04-07 01:51:49 +00:00 committed by David S. Miller
parent ef3313e84a
commit 4683f42fde
1 changed files with 2 additions and 2 deletions

View File

@ -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;