From 1bb4e4c787e04c9bcc3b235d236ba2357bc98b64 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Fri, 23 Feb 2018 15:12:55 -0500 Subject: [PATCH] qmp-input: Don't consume input when checking has_member Commit e8316d7 mistakenly passed consume=true within qmp_input_optional() when checking if an optional member was present, but the mistake was silently ignored since the code happily let us extract a member more than once. Fix qmp_input_optional() to not consume anything, then tighten up the input visitor to ensure that a member is consumed exactly once (all generated code follows this pattern; and the new assert will catch any hand-written code that tries to visit the same key more than once). Backports commit e5826a2fd727f0be54a81083f31fe02a275465cd from qemu --- qemu/qapi/qmp-input-visitor.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/qemu/qapi/qmp-input-visitor.c b/qemu/qapi/qmp-input-visitor.c index 7981a30d..6ebd0f88 100644 --- a/qemu/qapi/qmp-input-visitor.c +++ b/qemu/qapi/qmp-input-visitor.c @@ -55,16 +55,19 @@ static QObject *qmp_input_get_object(QmpInputVisitor *qiv, { StackObject *tos = &qiv->stack[qiv->nb_stack - 1]; QObject *qobj = tos->obj; + QObject *ret; assert(qobj); /* If we have a name, and we're in a dictionary, then return that * value. */ if (name && qobject_type(qobj) == QTYPE_QDICT) { - if (tos->h && consume) { - g_hash_table_remove(tos->h, name); + ret = qdict_get(qobject_to_qdict(qobj), name); + if (tos->h && consume && ret) { + bool removed = g_hash_table_remove(tos->h, name); + assert(removed); } - return qdict_get(qobject_to_qdict(qobj), name); + return ret; } /* If we are in the middle of a list, then return the next element @@ -139,7 +142,7 @@ static void qmp_input_start_struct(Visitor *v, const char *name, void **obj, size_t size, Error **errp) { QmpInputVisitor *qiv = to_qiv(v); - QObject *qobj = qmp_input_get_object(qiv, name, true); + QObject *qobj = qmp_input_get_object(qiv, name, false); Error *err = NULL; if (obj) {