a socket from a regular socket to a listening socket able to accept new
connections. As part of this state transition, solisten() calls into the
protocol to update protocol-layer state. There were several bugs in this
implementation that could result in a race wherein a TCP SYN received
in the interval between the protocol state transition and the shortly
following socket layer transition would result in a panic in the TCP code,
as the socket would be in the TCPS_LISTEN state, but the socket would not
have the SO_ACCEPTCONN flag set.
This change does the following:
- Pushes the socket state transition from the socket layer solisten() to
to socket "library" routines called from the protocol. This permits
the socket routines to be called while holding the protocol mutexes,
preventing a race exposing the incomplete socket state transition to TCP
after the TCP state transition has completed. The check for a socket
layer state transition is performed by solisten_proto_check(), and the
actual transition is performed by solisten_proto().
- Holds the socket lock for the duration of the socket state test and set,
and over the protocol layer state transition, which is now possible as
the socket lock is acquired by the protocol layer, rather than vice
versa. This prevents additional state related races in the socket
layer.
This permits the dual transition of socket layer and protocol layer state
to occur while holding locks for both layers, making the two changes
atomic with respect to one another. Similar changes are likely require
elsewhere in the socket/protocol code.
Reported by: Peter Holm <peter@holm.cc>
Review and fixes from: emax, Antoine Brodin <antoine.brodin@laposte.net>
Philosophical head nod: gnn
- refactor ngd_constructor, so that make_dev() is called without
any locks held, since it mallocs memory with M_WAITOK flag.
- rename global mtx, to have name different to per-node mtx
MFC after: 2 weeks
removes netgraph node and unwraps Ethernet interface.
This gives us ability to unload ng_ether.ko, when all interfaces
are detached, making ng_ether(4) developers happy.
Reviewed by: ru
a definite setup was broken: two ng_ksockets are connected to each other,
connect()ed to different remote hosts, and bind()ed to different local
interfaces. In this case one ng_ksocket is fooled with tag from the other
one.
Put node id into tag. In rcvdata method utilize tag only if it has our
own id inside or id equals zero. The latter case is added to support
packets send by some third, not ng_ksocket node.
MFC after: 1 week
with net byte order. Change byte order to net in ng_ipfw_input(), change
byte order to host before ip_output(), do not change before ip_input().
In collaboration with: ru
The difference is that the callout function installed via the
ng_callout() method is guaranteed to NOT fire after the shutdown
method was run (when a node is marked NGF_INVALID). Also, the
shutdown method and the callout function are guaranteed to NOT
run at the same time, as both require the writer lock. Thus
we can safely ignore a zero return value from ng_uncallout()
(callout_stop()) in shutdown methods, and go on with freeing
the node.
The said revision broke the node shutdown -- ng_bridge_timeout()
is no longer fired after ng_bridge_shutdown() was run, resulting
in a memory leak, dead nodes, and inability to unload the module.
Fix this by cancelling the callout on shutdown, and moving part
responsible for freeing a node resources from ng_bridge_timer()
to ng_bridge_shutdown().
Noticed by: ru
Submitted by: glebius, ru
before entering ng_netflow. In this case it will have not NULL m_pkthdr.rcvif.
However, it will enter ng_iface soon with another index. So let in_ifIndex
value configured by user override m_pkthdr.rcvif.
Reported by: Damir Bikmuhametov
MFC after: 1 week
