MHD_get_daemon_info(): fixed unaligned memory access

5 files changed, 55 insertions, 33 deletions

diff --git a/src/include/microhttpd.h b/src/include/microhttpd.h
index cf8216d0..b4bc85e3 100644
--- a/src/include/microhttpd.h
+++ b/src/include/microhttpd.h
@@ -4529,8 +4529,9 @@ union MHD_DaemonInfo
 
 
 /**
- * Obtain information about the given daemon
- * (not fully implemented!).
+ * Obtain information about the given daemon.
+ * The returned pointer is invalidated with the next call of this function or
+ * when the daemon is stopped.
  *
  * @param daemon what daemon to get information about
  * @param info_type what information is desired?
diff --git a/src/microhttpd/daemon.c b/src/microhttpd/daemon.c
index 6cbd9ad5..35708b27 100644
--- a/src/microhttpd/daemon.c
+++ b/src/microhttpd/daemon.c
@@ -7813,8 +7813,9 @@ MHD_stop_daemon (struct MHD_Daemon *daemon)
 
 
 /**
- * Obtain information about the given daemon
- * (not fully implemented!).
+ * Obtain information about the given daemon.
+ * The returned pointer is invalidated with the next call of this function or
+ * when the daemon is stopped.
  *
  * @param daemon what daemon to get information about
  * @param info_type what information is desired?
@@ -7837,10 +7838,12 @@ MHD_get_daemon_info (struct MHD_Daemon *daemon,
   case MHD_DAEMON_INFO_MAC_KEY_SIZE:
     return NULL;   /* no longer supported */
   case MHD_DAEMON_INFO_LISTEN_FD:
-    return (const union MHD_DaemonInfo *) &daemon->listen_fd;
+    daemon->daemon_info_dummy_listen_fd.listen_fd = daemon->listen_fd;
+    return &daemon->daemon_info_dummy_listen_fd;
 #ifdef EPOLL_SUPPORT
   case MHD_DAEMON_INFO_EPOLL_FD:
-    return (const union MHD_DaemonInfo *) &daemon->epoll_fd;
+    daemon->daemon_info_dummy_epoll_fd.epoll_fd = daemon->epoll_fd;
+    return &daemon->daemon_info_dummy_epoll_fd;
 #endif
   case MHD_DAEMON_INFO_CURRENT_CONNECTIONS:
     if (0 == (daemon->options & MHD_USE_INTERNAL_POLLING_THREAD))
@@ -7862,11 +7865,15 @@ MHD_get_daemon_info (struct MHD_Daemon *daemon,
       }
     }
 #endif
-    return (const union MHD_DaemonInfo *) &daemon->connections;
+    daemon->daemon_info_dummy_num_connections.num_connections
+      = daemon->connections;
+    return &daemon->daemon_info_dummy_num_connections;
   case MHD_DAEMON_INFO_FLAGS:
-    return (const union MHD_DaemonInfo *) &daemon->options;
+    daemon->daemon_info_dummy_flags.flags = daemon->options;
+    return &daemon->daemon_info_dummy_flags;
   case MHD_DAEMON_INFO_BIND_PORT:
-    return (const union MHD_DaemonInfo *) &daemon->port;
+    daemon->daemon_info_dummy_port.port = daemon->port;
+    return &daemon->daemon_info_dummy_port;
   default:
     return NULL;
   }
diff --git a/src/microhttpd/internal.h b/src/microhttpd/internal.h
index 094c26ba..fc8ec0c6 100644
--- a/src/microhttpd/internal.h
+++ b/src/microhttpd/internal.h
@@ -2164,6 +2164,34 @@ struct MHD_Daemon
    * #MHD_OPTION_ARRAY are counted.
    */
   size_t num_opts;
+
+  /* TODO: replace with a single member */
+  /**
+   * The value to be returned by #MHD_get_daemon_info()
+   */
+  union MHD_DaemonInfo daemon_info_dummy_listen_fd;
+
+#ifdef EPOLL_SUPPORT
+  /**
+   * The value to be returned by #MHD_get_daemon_info()
+   */
+  union MHD_DaemonInfo daemon_info_dummy_epoll_fd;
+#endif /* EPOLL_SUPPORT */
+
+  /**
+   * The value to be returned by #MHD_get_daemon_info()
+   */
+  union MHD_DaemonInfo daemon_info_dummy_num_connections;
+
+  /**
+   * The value to be returned by #MHD_get_daemon_info()
+   */
+  union MHD_DaemonInfo daemon_info_dummy_flags;
+
+  /**
+   * The value to be returned by #MHD_get_daemon_info()
+   */
+  union MHD_DaemonInfo daemon_info_dummy_port;
 };
 
 
diff --git a/src/microhttpd/test_upgrade.c b/src/microhttpd/test_upgrade.c
index acaecf9f..d4b97718 100644
--- a/src/microhttpd/test_upgrade.c
+++ b/src/microhttpd/test_upgrade.c
@@ -1257,7 +1257,7 @@ test_upgrade (int flags,
   struct MHD_Daemon *d = NULL;
   struct wr_socket *sock;
   struct sockaddr_in sa;
-  const union MHD_DaemonInfo *real_flags;
+  enum MHD_FLAG used_flags;
   const union MHD_DaemonInfo *dinfo;
 #if defined(HTTPS_SUPPORT) && defined(HAVE_FORK) && defined(HAVE_WAITPID)
   pid_t pid = -1;
@@ -1296,10 +1296,11 @@ test_upgrade (int flags,
 #endif /* HTTPS_SUPPORT */
   if (NULL == d)
     mhdErrorExitDesc ("MHD_start_daemon() failed");
-  real_flags = MHD_get_daemon_info (d,
-                                    MHD_DAEMON_INFO_FLAGS);
-  if (NULL == real_flags)
+  dinfo = MHD_get_daemon_info (d,
+                               MHD_DAEMON_INFO_FLAGS);
+  if (NULL == dinfo)
     mhdErrorExitDesc ("MHD_get_daemon_info() failed");
+  used_flags = dinfo->flags;
   dinfo = MHD_get_daemon_info (d,
                                MHD_DAEMON_INFO_BIND_PORT);
   if ( (NULL == dinfo) ||
@@ -1347,15 +1348,7 @@ test_upgrade (int flags,
                            sock))
     externalErrorExitDesc ("pthread_create() failed");
   if (0 == (flags & MHD_USE_INTERNAL_POLLING_THREAD) )
-  {
-    enum MHD_FLAG used_flags;
-
-    /* make address sanitizer happy */
-    memcpy (&used_flags,
-            real_flags /* ->flags */,
-            sizeof (used_flags));
     run_mhd_loop (d, used_flags);
-  }
   if (0 != pthread_join (pt_client,
                          NULL))
     externalErrorExitDesc ("pthread_join() failed");
diff --git a/src/microhttpd/test_upgrade_large.c b/src/microhttpd/test_upgrade_large.c
index e04e7ebf..477a0851 100644
--- a/src/microhttpd/test_upgrade_large.c
+++ b/src/microhttpd/test_upgrade_large.c
@@ -1445,7 +1445,7 @@ test_upgrade (int flags,
   struct MHD_Daemon *d = NULL;
   struct wr_socket *sock;
   struct sockaddr_in sa;
-  const union MHD_DaemonInfo *real_flags;
+  enum MHD_FLAG used_flags;
   const union MHD_DaemonInfo *dinfo;
 #if defined(HTTPS_SUPPORT) && defined(HAVE_FORK) && defined(HAVE_WAITPID)
   pid_t pid = -1;
@@ -1486,10 +1486,11 @@ test_upgrade (int flags,
 #endif /* HTTPS_SUPPORT */
   if (NULL == d)
     mhdErrorExitDesc ("MHD_start_daemon() failed");
-  real_flags = MHD_get_daemon_info (d,
-                                    MHD_DAEMON_INFO_FLAGS);
-  if (NULL == real_flags)
+  dinfo = MHD_get_daemon_info (d,
+                               MHD_DAEMON_INFO_FLAGS);
+  if (NULL == dinfo)
     mhdErrorExitDesc ("MHD_get_daemon_info() failed");
+  used_flags = dinfo->flags;
   dinfo = MHD_get_daemon_info (d,
                                MHD_DAEMON_INFO_BIND_PORT);
   if ( (NULL == dinfo) ||
@@ -1543,15 +1544,7 @@ test_upgrade (int flags,
                            sock))
     externalErrorExitDesc ("pthread_create() failed");
   if (0 == (flags & MHD_USE_INTERNAL_POLLING_THREAD) )
-  {
-    enum MHD_FLAG used_flags;
-
-    /* make address sanitizer happy */
-    memcpy (&used_flags,
-            real_flags /* ->flags */,
-            sizeof (used_flags));
     run_mhd_loop (d, used_flags);
-  }
   if (0 != pthread_join (pt_client,
                          NULL))
     externalErrorExitDesc ("pthread_join() failed");