mirror of
https://github.com/torvalds/linux.git
synced 2024-11-28 07:01:32 +00:00
d217472410
Init method just allocates memory for new cfg, and assigns net_generic(net, caif_net_id). Despite there is synchronize_rcu() on error path in cfcnfg_create(), in real this function does not use global lists, so it looks like this synchronize_rcu() is some legacy inheritance. Exit method removes caif devices under rtnl_lock(). There could be a problem, if someone from foreign net pernet_operations dereference caif_net_id of this net. It's dereferenced in get_cfcnfg() and caif_device_list(). get_cfcnfg() is used from netdevice notifiers, where they are called under rtnl_lock(). The notifiers can't be called from foreign nets pernet_operations. Also, it's used from caif_disconnect_client() and from caif_connect_client(). The both of the functions work with caif socket, and there is the only possibility to have a socket, when the net is dead. This may happen only of the socket was created as kern using sk_alloc(). Grep by PF_CAIF shows we do not create kern caif sockets, so get_cfcnfg() is safe. caif_device_list() is used in netdevice notifiers and exit method under rtnl lock. Also, from caif_get() used in the netdev notifiers and in caif_flow_cb(). The last item is skb destructor. Since there are no kernel caif sockets nobody can send net a packet in parallel with init/exit, so this is also safe. So, these pernet_operations are safe to be async. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|---|---|---|
| .. | ||
| caif_dev.c | ||
| caif_socket.c | ||
| caif_usb.c | ||
| cfcnfg.c | ||
| cfctrl.c | ||
| cfdbgl.c | ||
| cfdgml.c | ||
| cffrml.c | ||
| cfmuxl.c | ||
| cfpkt_skbuff.c | ||
| cfrfml.c | ||
| cfserl.c | ||
| cfsrvl.c | ||
| cfutill.c | ||
| cfveil.c | ||
| cfvidl.c | ||
| chnl_net.c | ||
| Kconfig | ||
| Makefile | ||