Lock down a socket, milestone 1.

o Add a mutex (sb_mtx) to struct sockbuf. This protects the data in a
  socket buffer. The mutex in the receive buffer also protects the data
  in struct socket.

o Determine the lock strategy for each members in struct socket.

o Lock down the following members:

  - so_count
  - so_options
  - so_linger
  - so_state

o Remove *_locked() socket APIs.  Make the following socket APIs
  touching the members above now require a locked socket:

 - sodisconnect()
 - soisconnected()
 - soisconnecting()
 - soisdisconnected()
 - soisdisconnecting()
 - sofree()
 - soref()
 - sorele()
 - sorwakeup()
 - sotryfree()
 - sowakeup()
 - sowwakeup()

Reviewed by:	alfred

1 files changed, 4 insertions, 1 deletions

diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index b7a882f..3627832 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1837,15 +1837,18 @@ ip_savecontrol(inp, mp, ip, m)
 	register struct ip *ip;
 	register struct mbuf *m;
 {
+	SOCK_LOCK(inp->inp_socket);
 	if (inp->inp_socket->so_options & SO_TIMESTAMP) {
 		struct timeval tv;
 
+		SOCK_UNLOCK(inp->inp_socket);
 		microtime(&tv);
 		*mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
 			SCM_TIMESTAMP, SOL_SOCKET);
 		if (*mp)
 			mp = &(*mp)->m_next;
-	}
+	} else
+		SOCK_UNLOCK(inp->inp_socket);
 	if (inp->inp_flags & INP_RECVDSTADDR) {
 		*mp = sbcreatecontrol((caddr_t) &ip->ip_dst,
 		    sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);