gpg-agent: Avoid getting stuck in shutdown pending state.
authorWerner Koch <wk@gnupg.org>
Mon, 13 Nov 2017 09:52:36 +0000 (10:52 +0100)
committerWerner Koch <wk@gnupg.org>
Mon, 20 Nov 2017 10:55:34 +0000 (11:55 +0100)
* agent/gpg-agent.c (handle_connections): Always check inotify fds.
--

I noticed a gpg-agent processed, probably in shutdown_pending state,
which was selecting on only these two inotify fds.  The select
returned immediately but because we did not handle the fds in
shutdown_pending state they were not read and the next select call
returned one of them immediately again.  Actually that should not
hanppen because the

          if (active_connections == 0)
            break; /* ready */

should have terminated the loop.  For unknown reasons (maybe be just a
connection thread terminated in a gdb session) that did not happen.
By moving the check outside of the shutdown_pending condition and
closing the fd after they have been triggered the code should be more
robust.

Signed-off-by: Werner Koch <wk@gnupg.org>
(cherry picked from commit 5d83eb9226c0ce608ec284d8c9bc22ce84a00c25)

agent/gpg-agent.c

index 2e19d19..0b2b982 100644 (file)
@@ -3000,27 +3000,34 @@ handle_connections (gnupg_fd_t listen_fd,
           next timeout.  */
        continue;
 
+      /* The inotify fds are set even when a shutdown is pending (see
+       * above).  So we must handle them in any case.  To avoid that
+       * they trigger a second time we close them immediately.  */
+      if (sock_inotify_fd != -1
+          && FD_ISSET (sock_inotify_fd, &read_fdset)
+          && gnupg_inotify_has_name (sock_inotify_fd, GPG_AGENT_SOCK_NAME))
+        {
+          shutdown_pending = 1;
+          close (sock_inotify_fd);
+          sock_inotify_fd = -1;
+          log_info ("socket file has been removed - shutting down\n");
+        }
+
+      if (home_inotify_fd != -1
+          && FD_ISSET (home_inotify_fd, &read_fdset))
+        {
+          shutdown_pending = 1;
+          close (home_inotify_fd);
+          home_inotify_fd = -1;
+          log_info ("homedir has been removed - shutting down\n");
+        }
+
       if (!shutdown_pending)
         {
           int idx;
           ctrl_t ctrl;
           npth_t thread;
 
-          if (sock_inotify_fd != -1
-              && FD_ISSET (sock_inotify_fd, &read_fdset)
-              && gnupg_inotify_has_name (sock_inotify_fd, GPG_AGENT_SOCK_NAME))
-            {
-              shutdown_pending = 1;
-              log_info ("socket file has been removed - shutting down\n");
-            }
-
-          if (home_inotify_fd != -1
-              && FD_ISSET (home_inotify_fd, &read_fdset))
-            {
-              shutdown_pending = 1;
-              log_info ("homedir has been removed - shutting down\n");
-            }
-
           for (idx=0; idx < DIM(listentbl); idx++)
             {
               if (listentbl[idx].l_fd == GNUPG_INVALID_FD)