Bluetooth: Fix potential double-frees of L2CAP skbs
authorJohan Hedberg <johan.hedberg@intel.com>
Thu, 10 Oct 2013 11:33:37 +0000 (13:33 +0200)
committerMarcel Holtmann <marcel@holtmann.org>
Thu, 10 Oct 2013 12:00:34 +0000 (05:00 -0700)
commitc4e5bafa661126b7b42459ad32d4c2cc589ef8fb
treeb0647af6398962acb3532679c71221a37fc6eb6e
parent9ecb3e24258f1ff4b9937602962ae12e3b57f98d
Bluetooth: Fix potential double-frees of L2CAP skbs

The l2cap_recv_frame function is expected to take ownership and
eventually free the skb passed to it. We need to ensure that the
conn->rx_skb pointer is no longer reachable when calling
l2cap_recv_frame so that no other function, such as l2cap_conn_del, may
think that it can free conn->rx_skb.

An actual situation when this can happen is when smp_sig_channel (called
from l2cap_recv_frame) fails and l2cap_conn_del gets called as a
consequence. The l2cap_conn_del function would then try to free
conn->rx_skb, but as the same skb was just passed to smp_sig_channel and
freed we get a double-free.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
net/bluetooth/l2cap_core.c