secret: Properly handle @def after virSecretObjAdd in driver

Since the virSecretObjListAdd technically consumes @def on success,
the secretDefineXML should set @def = NULL immediately and process
the remaining calls using a new @objDef variable. We can use use
VIR_STEAL_PTR since we know the Add function just stores @def in
obj->def.

Because we steal @def into @objDef, if we jump to restore_backup:
and @backup is set, then we need to ensure the @def would be
free'd properly, so we'll steal it back from @objDef. For the other
condition this fixes a double free of @def if the code had jumped to
@backup == NULL thus calling virSecretObjListRemove without setting
@def = NULL. In this case, the subsequent call to DefFree would
succeed and free @def; however, the call to EndAPI would also
call DefFree because the Unref done would be the last one for
the @obj meaning the obj->def would be used to call DefFree,
but it's already been free'd because @def wasn't managed right
within this error path.

Signed-off-by: John Ferlan <jferlan@redhat.com>
This commit is contained in:
John Ferlan 2017-06-01 08:17:52 -04:00
parent 7ca17da9f2
commit e4c0aff215

View File

@ -210,6 +210,7 @@ secretDefineXML(virConnectPtr conn,
{
virSecretPtr ret = NULL;
virSecretObjPtr obj = NULL;
virSecretDefPtr objDef;
virSecretDefPtr backup = NULL;
virSecretDefPtr def;
virObjectEventPtr event = NULL;
@ -225,8 +226,9 @@ secretDefineXML(virConnectPtr conn,
if (!(obj = virSecretObjListAdd(driver->secrets, def,
driver->configDir, &backup)))
goto cleanup;
VIR_STEAL_PTR(objDef, def);
if (!def->isephemeral) {
if (!objDef->isephemeral) {
if (backup && backup->isephemeral) {
if (virSecretObjSaveData(obj) < 0)
goto restore_backup;
@ -248,28 +250,27 @@ secretDefineXML(virConnectPtr conn,
/* Saved successfully - drop old values */
virSecretDefFree(backup);
event = virSecretEventLifecycleNew(def->uuid,
def->usage_type,
def->usage_id,
event = virSecretEventLifecycleNew(objDef->uuid,
objDef->usage_type,
objDef->usage_id,
VIR_SECRET_EVENT_DEFINED,
0);
ret = virGetSecret(conn,
def->uuid,
def->usage_type,
def->usage_id);
def = NULL;
objDef->uuid,
objDef->usage_type,
objDef->usage_id);
goto cleanup;
restore_backup:
/* If we have a backup, then secret was defined before, so just restore
* the backup. The current def will be handled below.
* Otherwise, this is a new secret, thus remove it.
*/
if (backup)
* the backup; otherwise, this is a new secret, thus remove it. */
if (backup) {
virSecretObjSetDef(obj, backup);
else
VIR_STEAL_PTR(def, objDef);
} else {
virSecretObjListRemove(driver->secrets, obj);
}
cleanup:
virSecretDefFree(def);