From 74d8c9d99d1984d78ac8d8e28266525b2b190b8b Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Fri, 3 Mar 2017 13:32:21 +0100 Subject: [PATCH] qga: Fix crash on non-dictionary QMP argument The value of key 'arguments' must be a JSON object. qemu-ga neglects to check, and crashes. To reproduce, send { 'execute': 'guest-sync', 'arguments': [] } to qemu-ga. do_qmp_dispatch() uses qdict_get_qdict() to get the arguments. When not a JSON object, this gets a null pointer, which flows through the generated marshalling function to qobject_input_visitor_new(), where it fails the assertion. qmp_dispatch_check_obj() needs to catch this error. QEMU isn't affected, because it runs qmp_check_input_obj() first, which basically duplicates qmp_dispatch_check_obj()'s checks, plus the missing one. Fix by copying the missing one from qmp_check_input_obj() to qmp_dispatch_check_obj(). Signed-off-by: Markus Armbruster Cc: Michael Roth Reviewed-by: Eric Blake Message-Id: <1488544368-30622-2-git-send-email-armbru@redhat.com> --- qapi/qmp-dispatch.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/qapi/qmp-dispatch.c b/qapi/qmp-dispatch.c index 48bec2072b..621922ffa2 100644 --- a/qapi/qmp-dispatch.c +++ b/qapi/qmp-dispatch.c @@ -47,7 +47,13 @@ static QDict *qmp_dispatch_check_obj(const QObject *request, Error **errp) return NULL; } has_exec_key = true; - } else if (strcmp(arg_name, "arguments")) { + } else if (!strcmp(arg_name, "arguments")) { + if (qobject_type(arg_obj) != QTYPE_QDICT) { + error_setg(errp, QERR_QMP_BAD_INPUT_OBJECT_MEMBER, + "arguments", "object"); + return NULL; + } + } else { error_setg(errp, QERR_QMP_EXTRA_MEMBER, arg_name); return NULL; }