From 6d4cd408686f5ae60b2b3b94b79f48ddedc2f39d Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Thu, 4 Jul 2013 15:09:18 +0200 Subject: [PATCH] qemu-option: Fix qemu_opts_set_defaults() for corner cases Commit 4f6dd9a changed the initialization of opts in opts_parse() to this: if (defaults) { if (!id && !QTAILQ_EMPTY(&list->head)) { opts = qemu_opts_find(list, NULL); } else { opts = qemu_opts_create(list, id, 0); } } else { opts = qemu_opts_create(list, id, 1); } Same as before for !defaults. If defaults is true, and params has no ID, and options exist, we use the first assignment. It sets opts to null if all options have an ID. opts_parse() then returns null. qemu_opts_set_defaults() asserts the value is non-null. It's the only caller that passes true for defaults. To reproduce, try "-M xenpv -machine id=foo" (yes, "id=foo" is silly, but it shouldn't crash). I believe the function attempts to do the following: If options don't yet exist, create new options Else, if defaults, modify the existing options Else, if list->merge_lists, modify the existing options Else, fail A straightforward call of qemu_opts_create() does exactly that. Cc: Jan Kiszka Signed-off-by: Markus Armbruster Message-id: 1372943363-24081-3-git-send-email-armbru@redhat.com Signed-off-by: Anthony Liguori --- util/qemu-option.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) diff --git a/util/qemu-option.c b/util/qemu-option.c index 2715f27e41..e0ef426daa 100644 --- a/util/qemu-option.c +++ b/util/qemu-option.c @@ -914,15 +914,7 @@ static QemuOpts *opts_parse(QemuOptsList *list, const char *params, get_opt_value(value, sizeof(value), p+4); id = value; } - if (defaults) { - if (!id && !QTAILQ_EMPTY(&list->head)) { - opts = qemu_opts_find(list, NULL); - } else { - opts = qemu_opts_create(list, id, 0, &local_err); - } - } else { - opts = qemu_opts_create(list, id, 1, &local_err); - } + opts = qemu_opts_create(list, id, !defaults, &local_err); if (opts == NULL) { if (error_is_set(&local_err)) { qerror_report_err(local_err);