winbind: fix smbd hanging on Solaris when winbindd closes socket.

On some versions of Solaris, we observed a strange effect of close(2)
on a socket: After the server (here winbindd) called close, the client fd
was not marked as readable for select. And a write call to the fd did
not produce an error EPIPE but just returned as if successful.

So while winbindd had called remove_client(), the corresponding smbd
still thought that it was connected, but failed to retrieve answers
for its queries.

This patch works around the problem by forcing the client fd to
the readable state: Just write one byte into the socket before
closing.

Michael

diff --git a/source/winbindd/winbindd.c b/source/winbindd/winbindd.c
index 876b2e8390215189ddd054b6d6d078baee84c7c6..efc104903a72e764950f4fc7f47eaadbd66348e3 100644 (file)
--- a/source/winbindd/winbindd.c
+++ b/source/winbindd/winbindd.c
@@ -745,12 +745,17 @@ static void new_connection(int listen_sock, bool privileged)
 
 static void remove_client(struct winbindd_cli_state *state)
 {
+       char c = 0;
+
        /* It's a dead client - hold a funeral */
        
        if (state == NULL) {
                return;
        }
-               
+
+       /* tell client, we are closing ... */
+       write(state->sock, &c, sizeof(c));
+
        /* Close socket */
                
        close(state->sock);