Bug 18446: Keep umask for session bus

Signed-off-by: Colin Walters <walters@verbum.org>

7 files changed, 55 insertions, 2 deletions

diff --git a/bus/bus.c b/bus/bus.c
index d9fd2d9e..e5733fec 100644
--- a/bus/bus.c
+++ b/bus/bus.c
@@ -54,6 +54,7 @@ struct BusContext
   BusMatchmaker *matchmaker;
   BusLimits limits;
   unsigned int fork : 1;
+  unsigned int keep_umask : 1;
 };
 
 static dbus_int32_t server_data_slot = -1;
@@ -384,6 +385,7 @@ process_config_first_time_only (BusContext      *context,
     }
 
   context->fork = bus_config_parser_get_fork (parser);
+  context->keep_umask = bus_config_parser_get_keep_umask (parser);
   
   _DBUS_ASSERT_ERROR_IS_CLEAR (error);
   retval = TRUE;
@@ -708,7 +710,8 @@ bus_context_new (const DBusString *config_file,
         
         if (!_dbus_become_daemon (context->pidfile ? &u : NULL, 
                                   print_pid_pipe,
-                                  error))
+                                  error,
+                                  context->keep_umask))
           {
             _DBUS_ASSERT_ERROR_IS_SET (error);
             goto failed;
diff --git a/bus/config-parser-common.c b/bus/config-parser-common.c
index 6e4bb701..1e0f7f91 100644
--- a/bus/config-parser-common.c
+++ b/bus/config-parser-common.c
@@ -114,6 +114,10 @@ bus_config_parser_element_name_to_type (const char *name)
     {
       return ELEMENT_ASSOCIATE;
     }
+  else if (strcmp (name, "keep_umask") == 0)
+    {
+      return ELEMENT_KEEP_UMASK;
+    }
   return ELEMENT_NONE;
 }
 
@@ -162,6 +166,8 @@ bus_config_parser_element_type_to_name (ElementType type)
       return "selinux";
     case ELEMENT_ASSOCIATE:
       return "associate";
+    case ELEMENT_KEEP_UMASK:
+      return "keep_umask";
     }
 
   _dbus_assert_not_reached ("bad element type");
diff --git a/bus/config-parser-common.h b/bus/config-parser-common.h
index 3718c958..01eb118b 100644
--- a/bus/config-parser-common.h
+++ b/bus/config-parser-common.h
@@ -47,7 +47,8 @@ typedef enum
   ELEMENT_SELINUX,
   ELEMENT_ASSOCIATE,
   ELEMENT_STANDARD_SESSION_SERVICEDIRS,
-  ELEMENT_STANDARD_SYSTEM_SERVICEDIRS
+  ELEMENT_STANDARD_SYSTEM_SERVICEDIRS,
+  ELEMENT_KEEP_UMASK
 } ElementType;
 
 ElementType bus_config_parser_element_name_to_type (const char *element_name);
diff --git a/bus/config-parser.c b/bus/config-parser.c
index f9e0b7d7..5bb34f17 100644
--- a/bus/config-parser.c
+++ b/bus/config-parser.c
@@ -111,6 +111,8 @@ struct BusConfigParser
 
   unsigned int fork : 1; /**< TRUE to fork into daemon mode */
 
+  unsigned int keep_umask : 1; /**< TRUE to keep original umask when forking */
+
   unsigned int is_toplevel : 1; /**< FALSE if we are a sub-config-file inside another one */
 };
 
@@ -306,6 +308,9 @@ merge_included (BusConfigParser *parser,
   if (included->fork)
     parser->fork = TRUE;
 
+  if (included->keep_umask)
+    parser->keep_umask = TRUE;
+
   if (included->pidfile != NULL)
     {
       dbus_free (parser->pidfile);
@@ -698,6 +703,21 @@ start_busconfig_child (BusConfigParser   *parser,
       
       return TRUE;
     }
+  else if (element_type == ELEMENT_KEEP_UMASK)
+    {
+      if (!check_no_attributes (parser, "keep_umask", attribute_names, attribute_values, error))
+        return FALSE;
+
+      if (push_element (parser, ELEMENT_KEEP_UMASK) == NULL)
+        {
+          BUS_SET_OOM (error);
+          return FALSE;
+        }
+
+      parser->keep_umask = TRUE;
+      
+      return TRUE;
+    }
   else if (element_type == ELEMENT_PIDFILE)
     {
       if (!check_no_attributes (parser, "pidfile", attribute_names, attribute_values, error))
@@ -1947,6 +1967,7 @@ bus_config_parser_end_element (BusConfigParser   *parser,
     case ELEMENT_ALLOW:
     case ELEMENT_DENY:
     case ELEMENT_FORK:
+    case ELEMENT_KEEP_UMASK:
     case ELEMENT_SELINUX:
     case ELEMENT_ASSOCIATE:
     case ELEMENT_STANDARD_SESSION_SERVICEDIRS:
@@ -2232,6 +2253,7 @@ bus_config_parser_content (BusConfigParser   *parser,
     case ELEMENT_ALLOW:
     case ELEMENT_DENY:
     case ELEMENT_FORK:
+    case ELEMENT_KEEP_UMASK:
     case ELEMENT_STANDARD_SESSION_SERVICEDIRS:    
     case ELEMENT_STANDARD_SYSTEM_SERVICEDIRS:    
     case ELEMENT_SELINUX:
@@ -2554,6 +2576,12 @@ bus_config_parser_get_fork (BusConfigParser   *parser)
   return parser->fork;
 }
 
+dbus_bool_t
+bus_config_parser_get_keep_umask (BusConfigParser   *parser)
+{
+  return parser->keep_umask;
+}
+
 const char *
 bus_config_parser_get_pidfile (BusConfigParser   *parser)
 {
@@ -2947,6 +2975,9 @@ config_parsers_equal (const BusConfigParser *a,
   if (! bools_equal (a->fork, b->fork))
     return FALSE;
 
+  if (! bools_equal (a->keep_umask, b->keep_umask))
+    return FALSE;
+
   if (! bools_equal (a->is_toplevel, b->is_toplevel))
     return FALSE;
 
diff --git a/bus/config-parser.h b/bus/config-parser.h
index ec0dfed1..6d69f3da 100644
--- a/bus/config-parser.h
+++ b/bus/config-parser.h
@@ -65,6 +65,7 @@ const char* bus_config_parser_get_type         (BusConfigParser *parser);
 DBusList**  bus_config_parser_get_addresses    (BusConfigParser *parser);
 DBusList**  bus_config_parser_get_mechanisms   (BusConfigParser *parser);
 dbus_bool_t bus_config_parser_get_fork         (BusConfigParser *parser);
+dbus_bool_t bus_config_parser_get_keep_umask   (BusConfigParser *parser);
 const char* bus_config_parser_get_pidfile      (BusConfigParser *parser);
 const char* bus_config_parser_get_servicehelper (BusConfigParser *parser);
 DBusList**  bus_config_parser_get_service_dirs (BusConfigParser *parser);
diff --git a/bus/dbus-daemon.1.in b/bus/dbus-daemon.1.in
index 5599afe6..7666f180 100644
--- a/bus/dbus-daemon.1.in
+++ b/bus/dbus-daemon.1.in
@@ -214,6 +214,13 @@ into the background, etc.). This is generally used
 rather than the \-\-fork command line option.
 
 .TP
+.I "<keep_umask>"
+    
+.PP
+If present, the bus daemon keeps its original umask when forking.
+This may be useful to avoid affecting the behavior of child processes.
+
+.TP
 .I "<listen>"
 
 .PP
diff --git a/bus/session.conf.in b/bus/session.conf.in
index b2dee5b3..794eb8da 100644
--- a/bus/session.conf.in
+++ b/bus/session.conf.in
@@ -8,6 +8,10 @@
   <!-- Our well-known bus type, don't change this -->
   <type>session</type>
 
+  <!-- If we fork, keep the user's original umask to avoid affecting
+       the behavior of child processes. -->
+  <keep_umask/>
+
   <listen>unix:tmpdir=@DBUS_SESSION_SOCKET_DIR@</listen>
 
   <standard_session_servicedirs />