kdbus: free returned buffer when the memory is no longer needed

[elogind.git] / src / libsystemd / sd-bus / bus-control.c

diff --git a/src/libsystemd/sd-bus/bus-control.c b/src/libsystemd/sd-bus/bus-control.c
index 204aed9d04f86d58adc5e103e1a4925141f20bc4..fa321d5315c79d6aa57aba84c860dbfc0fdd876c 100644 (file)
--- a/src/libsystemd/sd-bus/bus-control.c
+++ b/src/libsystemd/sd-bus/bus-control.c
@@ -58,12 +58,15 @@ static int bus_request_name_kernel(sd_bus *bus, const char *name, uint64_t flags
         assert(bus);
         assert(name);
 
-        l = strlen(name);
-        size = offsetof(struct kdbus_cmd_name, name) + l + 1;
-        n = alloca0(size);
+        l = strlen(name) + 1;
+        size = offsetof(struct kdbus_cmd_name, items) + KDBUS_ITEM_SIZE(l);
+        n = alloca0_align(size, 8);
         n->size = size;
         kdbus_translate_request_name_flags(flags, (uint64_t *) &n->flags);
-        memcpy(n->name, name, l+1);
+
+        n->items[0].size = KDBUS_ITEM_HEADER_SIZE + l;
+        n->items[0].type = KDBUS_ITEM_NAME;
+        memcpy(n->items[0].str, name, l);
 
 #ifdef HAVE_VALGRIND_MEMCHECK_H
         VALGRIND_MAKE_MEM_DEFINED(n, n->size);
@@ -144,16 +147,20 @@ _public_ int sd_bus_request_name(sd_bus *bus, const char *name, uint64_t flags)
 
 static int bus_release_name_kernel(sd_bus *bus, const char *name) {
         struct kdbus_cmd_name *n;
-        size_t l;
+        size_t size, l;
         int r;
 
         assert(bus);
         assert(name);
 
-        l = strlen(name);
-        n = alloca0(offsetof(struct kdbus_cmd_name, name) + l + 1);
-        n->size = offsetof(struct kdbus_cmd_name, name) + l + 1;
-        memcpy(n->name, name, l+1);
+        l = strlen(name) + 1;
+        size = offsetof(struct kdbus_cmd_name, items) + KDBUS_ITEM_SIZE(l);
+        n = alloca0_align(size, 8);
+        n->size = size;
+
+        n->items[0].size = KDBUS_ITEM_HEADER_SIZE + l;
+        n->items[0].type = KDBUS_ITEM_NAME;
+        memcpy(n->items[0].str, name, l);
 
 #ifdef HAVE_VALGRIND_MEMCHECK_H
         VALGRIND_MAKE_MEM_DEFINED(n, n->size);
@@ -162,7 +169,7 @@ static int bus_release_name_kernel(sd_bus *bus, const char *name) {
         if (r < 0)
                 return -errno;
 
-        return n->flags;
+        return 0;
 }
 
 static int bus_release_name_dbus1(sd_bus *bus, const char *name) {
@@ -216,6 +223,23 @@ _public_ int sd_bus_release_name(sd_bus *bus, const char *name) {
                 return bus_release_name_dbus1(bus, name);
 }
 
+static int kernel_cmd_free(sd_bus *bus, uint64_t offset)
+{
+        struct kdbus_cmd_free cmd;
+        int r;
+
+        assert(bus);
+
+        cmd.flags = 0;
+        cmd.offset = offset;
+
+        r = ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd);
+        if (r < 0)
+                return -errno;
+
+        return 0;
+}
+
 static int kernel_get_list(sd_bus *bus, uint64_t flags, char ***x) {
         struct kdbus_cmd_name_list cmd = {};
         struct kdbus_name_list *name_list;
@@ -235,31 +259,42 @@ static int kernel_get_list(sd_bus *bus, uint64_t flags, char ***x) {
 
         KDBUS_ITEM_FOREACH(name, name_list, names) {
 
+                struct kdbus_item *item;
+                const char *entry_name = NULL;
+
                 if ((flags & KDBUS_NAME_LIST_UNIQUE) && name->owner_id != previous_id) {
                         char *n;
 
-                        if (asprintf(&n, ":1.%llu", (unsigned long long) name->owner_id) < 0)
-                                return -ENOMEM;
+                        if (asprintf(&n, ":1.%llu", (unsigned long long) name->owner_id) < 0) {
+                                r = -ENOMEM;
+                                goto fail;
+                        }
 
                         r = strv_consume(x, n);
                         if (r < 0)
-                                return r;
+                                goto fail;
 
                         previous_id = name->owner_id;
                 }
 
-                if (name->size > sizeof(*name) && service_name_is_valid(name->name)) {
-                        r = strv_extend(x, name->name);
-                        if (r < 0)
-                                return -ENOMEM;
+                KDBUS_ITEM_FOREACH(item, name, items)
+                        if (item->type == KDBUS_ITEM_NAME)
+                                entry_name = item->str;
+
+                if (entry_name && service_name_is_valid(entry_name)) {
+                        r = strv_extend(x, entry_name);
+                        if (r < 0) {
+                                r = -ENOMEM;
+                                goto fail;
+                        }
                 }
         }
 
-        r = ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd.offset);
-        if (r < 0)
-                return -errno;
+        r = 0;
 
-        return 0;
+fail:
+        kernel_cmd_free(bus, cmd.offset);
+        return r;
 }
 
 static int bus_list_names_kernel(sd_bus *bus, char ***acquired, char ***activatable) {
@@ -367,7 +402,7 @@ static int bus_get_owner_kdbus(
         struct kdbus_cmd_conn_info *cmd;
         struct kdbus_conn_info *conn_info;
         struct kdbus_item *item;
-        size_t size;
+        size_t size, l;
         uint64_t m, id;
         int r;
 
@@ -375,13 +410,16 @@ static int bus_get_owner_kdbus(
         if (r < 0)
                 return r;
         if (r > 0) {
-                size = offsetof(struct kdbus_cmd_conn_info, name);
-                cmd = alloca0(size);
+                size = offsetof(struct kdbus_cmd_conn_info, items);
+                cmd = alloca0_align(size, 8);
                 cmd->id = id;
         } else {
-                size = offsetof(struct kdbus_cmd_conn_info, name) + strlen(name) + 1;
-                cmd = alloca0(size);
-                strcpy(cmd->name, name);
+                l = strlen(name) + 1;
+                size = offsetof(struct kdbus_cmd_conn_info, items) + KDBUS_ITEM_SIZE(l);
+                cmd = alloca0_align(size, 8);
+                cmd->items[0].size = KDBUS_ITEM_HEADER_SIZE + l;
+                cmd->items[0].type = KDBUS_ITEM_NAME;
+                memcpy(cmd->items[0].str, name, l);
         }
 
         cmd->size = size;
@@ -394,16 +432,25 @@ static int bus_get_owner_kdbus(
         conn_info = (struct kdbus_conn_info *) ((uint8_t *) bus->kdbus_buffer + cmd->offset);
 
         /* Non-activated names are considered not available */
-        if (conn_info->flags & KDBUS_HELLO_ACTIVATOR)
-                return name[0] == ':' ? -ENXIO : -ESRCH;
+        if (conn_info->flags & KDBUS_HELLO_ACTIVATOR) {
+                if (name[0] == ':')
+                        r = -ENXIO;
+                else
+                        r = -ESRCH;
+                goto fail;
+        }
 
         c = bus_creds_new();
-        if (!c)
-                return -ENOMEM;
+        if (!c) {
+                r = -ENOMEM;
+                goto fail;
+        }
 
         if (mask & SD_BUS_CREDS_UNIQUE_NAME) {
-                if (asprintf(&c->unique_name, ":1.%llu", (unsigned long long) conn_info->id) < 0)
-                        return -ENOMEM;
+                if (asprintf(&c->unique_name, ":1.%llu", (unsigned long long) conn_info->id) < 0) {
+                        r = -ENOMEM;
+                        goto fail;
+                }
 
                 c->mask |= SD_BUS_CREDS_UNIQUE_NAME;
         }
@@ -495,11 +542,9 @@ static int bus_get_owner_kdbus(
                                         goto fail;
                                 }
 
-                                if (!bus->cgroup_root) {
-                                        r = cg_get_root_path(&bus->cgroup_root);
-                                        if (r < 0)
-                                                goto fail;
-                                }
+                                r = bus_get_root_path(bus);
+                                if (r < 0)
+                                        goto fail;
 
                                 c->cgroup_root = strdup(bus->cgroup_root);
                                 if (!c->cgroup_root) {
@@ -581,7 +626,7 @@ static int bus_get_owner_kdbus(
         r = 0;
 
 fail:
-        ioctl(bus->input_fd, KDBUS_CMD_FREE, &cmd->offset);
+        kernel_cmd_free(bus, cmd->offset);
         return r;
 }
 
@@ -829,7 +874,7 @@ static int add_name_change_match(sd_bus *bus,
                             offsetof(struct kdbus_notify_name_change, name) +
                             l);
 
-                m = alloca0(sz);
+                m = alloca0_align(sz, 8);
                 m->size = sz;
                 m->cookie = cookie;
 
@@ -839,8 +884,8 @@ static int add_name_change_match(sd_bus *bus,
                         offsetof(struct kdbus_notify_name_change, name) +
                         l;
 
-                item->name_change.old.id = old_owner_id;
-                item->name_change.new.id = new_owner_id;
+                item->name_change.old_id.id = old_owner_id;
+                item->name_change.new_id.id = new_owner_id;
 
                 if (name)
                         memcpy(item->name_change.name, name, l);
@@ -889,7 +934,7 @@ static int add_name_change_match(sd_bus *bus,
                             offsetof(struct kdbus_item, id_change) +
                             sizeof(struct kdbus_notify_id_change));
 
-                m = alloca0(sz);
+                m = alloca0_align(sz, 8);
                 m->size = sz;
                 m->cookie = cookie;
 
@@ -1059,7 +1104,7 @@ int bus_add_match_internal_kernel(
         if (using_bloom)
                 sz += ALIGN8(offsetof(struct kdbus_item, data64) + bus->bloom_size);
 
-        m = alloca0(sz);
+        m = alloca0_align(sz, 8);
         m->size = sz;
         m->cookie = cookie;
 
@@ -1196,7 +1241,6 @@ int bus_remove_match_internal(
                 uint64_t cookie) {
 
         assert(bus);
-        assert(match);
 
         if (bus->is_kernel)
                 return bus_remove_match_internal_kernel(bus, cookie);