[SCTP]: Fix a race between module load and protosw access

There is a race is SCTP between the loading of the module
and the access by the socket layer to the protocol functions.
In particular, a list of addresss that SCTP maintains is
not initialized prior to the registration with the protosw.
Thus it is possible for a user application to gain access
to SCTP functions before everything has been initialized.
The problem shows up as odd crashes during connection
initializtion when we try to access the SCTP address list.

The solution is to refactor how we do registration and
initialize the lists prior to registering with the protosw.
Care must be taken since the address list initialization
depends on some other pieces of SCTP initialization.  Also
the clean-up in case of failure now also needs to be refactored.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
3 files changed