From ff02f101cb7db516bf1732bb74c42cb3b6259af1 Mon Sep 17 00:00:00 2001

From: David Herrmann <dh.herrmann@gmail.com>

Date: Wed, 17 Sep 2014 10:32:49 +0200

Subject: [PATCH] bus: fix error leak in bus_node_exists()

If we call into user callbacks, we must always propagate possible errors.

Fix bus_node_exists() to do that and adjust the callers (which already

partially propagated the error).

Also speed up that function by first checking for registered enumerators

and/or object-managers.

---

 src/libsystemd/sd-bus/bus-objects.c | 29 ++++++++++++++++++-----------

 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/src/libsystemd/sd-bus/bus-objects.c b/src/libsystemd/sd-bus/bus-objects.c

index ecac73a94d..0ab1119b58 100644

--- a/src/libsystemd/sd-bus/bus-objects.c

+++ b/src/libsystemd/sd-bus/bus-objects.c

@@ -820,7 +820,7 @@ static int property_get_all_callbacks_run(

         return 1;

 }

-static bool bus_node_exists(

+static int bus_node_exists(

                 sd_bus *bus,

                 struct node *n,

                 const char *path,

@@ -828,6 +828,7 @@ static bool bus_node_exists(

         struct node_vtable *c;

         struct node_callback *k;

+        int r;

         assert(bus);

         assert(n);

@@ -836,11 +837,14 @@ static bool bus_node_exists(

         /* Tests if there's anything attached directly to this node

          * for the specified path */

+        if (!require_fallback && (n->enumerators || n->object_managers))

+                return true;

+

         LIST_FOREACH(callbacks, k, n->callbacks) {

                 if (require_fallback && !k->is_fallback)

                         continue;

-                return true;

+                return 1;

         }

         LIST_FOREACH(vtables, c, n->vtables) {

@@ -849,13 +853,14 @@ static bool bus_node_exists(

                 if (require_fallback && !c->is_fallback)

                         continue;

-                if (node_vtable_get_userdata(bus, path, c, NULL, &error) > 0)

-                        return true;

+                r = node_vtable_get_userdata(bus, path, c, NULL, &error);

+                if (r != 0)

+                        return r;

                 if (bus->nodes_modified)

-                        return false;

+                        return 0;

         }

-        return !require_fallback && (n->enumerators || n->object_managers);

+        return 0;

 }

 static int process_introspect(

@@ -938,12 +943,12 @@ static int process_introspect(

                 /* Nothing?, let's see if we exist at all, and if not

                  * refuse to do anything */

                 r = bus_node_exists(bus, n, m->path, require_fallback);

-                if (r < 0)

-                        return r;

-                if (bus->nodes_modified)

-                        return 0;

-                if (r == 0)

+                if (r <= 0)

+                        goto finish;

+                if (bus->nodes_modified) {

+                        r = 0;

                         goto finish;

+                }

         }

         *found_object = true;

@@ -1293,6 +1298,8 @@ static int object_find_and_run(

                 r = bus_node_exists(bus, n, m->path, require_fallback);

                 if (r < 0)

                         return r;

+                if (bus->nodes_modified)

+                        return 0;

                 if (r > 0)

                         *found_object = true;

         }