Bluetooth: RFCOMM - Fix missing msg_namelen update in rfcomm_sock_recvmsg()
authorMathias Krause <minipli@googlemail.com>
Sun, 7 Apr 2013 01:51:50 +0000 (01:51 +0000)
committerDavid S. Miller <davem@davemloft.net>
Sun, 7 Apr 2013 20:28:00 +0000 (16:28 -0400)
If RFCOMM_DEFER_SETUP is set in the flags, rfcomm_sock_recvmsg() returns
early with 0 without updating the possibly set msg_namelen member. This,
in turn, leads to a 128 byte kernel stack leak in net/socket.c.

Fix this by updating msg_namelen in this case. For all other cases it
will be handled in bt_sock_stream_recvmsg().

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>
net/bluetooth/rfcomm/sock.c

index c23bae86263b6e98a21a8f69ae45190b827b2376..7c9224bcce178c493ce0a19f3f8250b1828d39b8 100644 (file)
@@ -608,6 +608,7 @@ static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 
        if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
                rfcomm_dlc_accept(d);
+               msg->msg_namelen = 0;
                return 0;
        }