Clean up the svr4 socket cache and streams code some to make it more easily

locked.
- Move all the svr4 socket cache code into svr4_socket.c, specifically
  move svr4_delete_socket() over from streams.c.  Make the socket cache
  entry structure and svr4_head private to svr4_socket.c as a result.
- Add a mutex to protect the svr4 socket cache.
- Change svr4_find_socket() to copy the sockaddr_un struct into a
  caller-supplied sockaddr_un rather than giving the caller a pointer to
  our internal one.  This removes the one case where code outside of
  svr4_socket.c could access data in the cache.
- Add an eventhandler for process_exit and process_exec to purge the cache
  of any entries for the exiting or execing process.
- Add methods to init and destroy the socket cache and call them from the
  svr4 ABI module's event handler.
- Conditionally grab Giant around socreate() in streamsopen().
- Use fdclose() instead of inlining it in streamsopen() when handling
  socreate() failure.
- Only allocate a stream structure and attach it to a socket in
  streamsopen().  Previously, if a svr4 program performed a stream
  operation on an arbitrary socket not opened via the streams device,
  we would attach streams state data to it and change f_ops of the
  associated struct file while it was in use.  The latter was especially
  not safe, and if a program wants a stream object it should open it via
  the streams device anyway.
- Don't bother locking so_emuldata in the streams code now that we only
  touch it right after creating a socket (in streamsopen()) or when
  tearing it down when the file is closed.
- Remove D_NEEDGIANT from the streams device as it is no longer needed.

1 files changed, 2 insertions, 4 deletions

diff --git a/sys/compat/svr4/svr4_stream.c b/sys/compat/svr4/svr4_stream.c
index 2d10cc9..5efb3b8 100644
--- a/sys/compat/svr4/svr4_stream.c
+++ b/sys/compat/svr4/svr4_stream.c
@@ -1554,13 +1554,11 @@ svr4_do_putmsg(td, uap, fp)
 			/* Maybe we've been given a device/inode pair */
 			dev_t *dev = SVR4_ADDROF(&sc);
 			ino_t *ino = (ino_t *) &dev[1];
-			sa = (struct sockaddr *)
-			    svr4_find_socket(td, fp, *dev, *ino);
-			if (sa == NULL) {
-				sa = (struct sockaddr *)&saun;
+			if (svr4_find_socket(td, fp, *dev, *ino, &saun) != 0) {
 				/* I guess we have it by name */
 				netaddr_to_sockaddr_un(&saun, &sc);
 			}
+			sa = (struct sockaddr *)&saun;
 			sasize = sizeof(saun);
 		}
 		break;