Avoid recursion in virtual_output_callback_func()

This solves a SEGV situation when using the management API while OpenVPN
is closing down.

The situation happens when the management socket has closed and OpenVPN
tries to write an error about this to the management socket.  What happens
is that

 virtual_output_callback_func() is called, which then calls
 -> man_output_list_push_finalize()
    -> man_output_standalone()
       -> man_write()  <-- this does the socket write
          -> man_io_error()
             -> x_msg()
                -> virtual_output_print()
                   -> virtual_output_callback_func() (recursion start)

virtual_output_callback_func() do have a mechanism to avoid recursion,
but that did not keep the recurse counter when
man_output_list_push_finalize()
is called.

This patch just reorganise the recursion block to also keep the counter
while
calling the other functions from virtual_output_callback_func()

Signed-off-by: David Sommerseth <davids@redhat.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: 1353063726-25113-1-git-send-email-dazo@users.sourceforge.net
URL: http://article.gmane.org/gmane.network.openvpn.devel/7130
(cherry picked from commit b2b66179f6dcc37de9582d5c3044f0357dda3df3)

diff --git a/src/openvpn/manage.c b/src/openvpn/manage.c
index d0bb4164f2d49b479d4d1729ca18b2927eb13e52..0a4542a7c6ef363da6a67e35dbe18ee16a6b22e0 100644 (file)
--- a/src/openvpn/manage.c
+++ b/src/openvpn/manage.c
@@ -287,13 +287,13 @@ virtual_output_callback_func (void *arg, const unsigned int flags, const char *s
 
 # define AF_DID_PUSH  (1<<0)
 # define AF_DID_RESET (1<<1)
-  unsigned int action_flags = 0;
 
   if (!recursive_level) /* don't allow recursion */
     {
       struct gc_arena gc = gc_new ();
       struct log_entry e;
       const char *out = NULL;
+      unsigned int action_flags = 0;
 
       ++recursive_level;
 
@@ -334,14 +334,15 @@ virtual_output_callback_func (void *arg, const unsigned int flags, const char *s
            }
        }
 
-      --recursive_level;
       gc_free (&gc);
-    }
 
-  if (action_flags & AF_DID_PUSH)
-    man_output_list_push_finalize (man);
-  if (action_flags & AF_DID_RESET)
-    man_reset_client_socket (man, true);
+      if (action_flags & AF_DID_PUSH)
+        man_output_list_push_finalize (man);
+      if (action_flags & AF_DID_RESET)
+        man_reset_client_socket (man, true);
+
+      --recursive_level;
+    }
 }
 
 /*