Extend coverage of SOCK_LOCK(so) to include so_count, the socket

reference count:

- Assert SOCK_LOCK(so) macros that directly manipulate so_count:
  soref(), sorele().

- Assert SOCK_LOCK(so) in macros/functions that rely on the state of
  so_count: sofree(), sotryfree().

- Acquire SOCK_LOCK(so) before calling these functions or macros in
  various contexts in the stack, both at the socket and protocol
  layers.

- In some cases, perform soisdisconnected() before sotryfree(), as
  this could result in frobbing of a non-present socket if
  sotryfree() actually frees the socket.

- Note that sofree()/sotryfree() will release the socket lock even if
  they don't free the socket.

Submitted by:	sam
Sponsored by:	FreeBSD Foundation
Obtained from:	BSD/OS

1 files changed, 2 insertions, 0 deletions

diff --git a/sys/netgraph/ng_ksocket.c b/sys/netgraph/ng_ksocket.c
index 56d1881..badc69c 100644
--- a/sys/netgraph/ng_ksocket.c
+++ b/sys/netgraph/ng_ksocket.c
@@ -1205,8 +1205,10 @@ ng_ksocket_finish_accept(priv_p priv)
 	head->so_qlen--;
 	so->so_qstate &= ~SQ_COMP;
 	so->so_head = NULL;
+	SOCK_LOCK(so);
 	soref(so);
 	so->so_state |= SS_NBIO;
+	SOCK_UNLOCK(so);
 	ACCEPT_UNLOCK();
 
 	/* XXX KNOTE(&head->so_rcv.sb_sel.si_note, 0); */