tree fbdd3dec3706dabe2ef7d83e8c78a1f4e224ceb3
parent 75b005b949d3dc93b526c3da0a750fd1fc9a703a
author Xin Long <lucien.xin@gmail.com> 1475088944 +0800
committer David S. Miller <davem@davemloft.net> 1475215737 -0400

sctp: fix the issue sctp_diag uses lock_sock in rcu_read_lock

When sctp dumps all the ep->assocs, it needs to lock_sock first,
but now it locks sock in rcu_read_lock, and lock_sock may sleep,
which would break rcu_read_lock.

This patch is to get and hold one sock when traversing the list.
After that and get out of rcu_read_lock, lock and dump it. Then
it will traverse the list again to get the next one until all
sctp socks are dumped.

For sctp_diag_dump_one, it fixes this issue by holding asoc and
moving cb() out of rcu_read_lock in sctp_transport_lookup_process.

Fixes: 8f840e47f190 ("sctp: add the sctp_diag.c file")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>