qemu_chr_parse_ringbuf() initializes the new ChardevRingbuf's @size to
the value of qemu_opt_get_size().  Except it first truncates the value
from uint64_t to int.  Fix that, so you can waste your RAM on
multi-gigabyte ring buffers.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 chardev/char-ringbuf.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/chardev/char-ringbuf.c b/chardev/char-ringbuf.c
index a9205ea..9275ae9 100644
--- a/chardev/char-ringbuf.c
+++ b/chardev/char-ringbuf.c
@@ -198,18 +198,14 @@ char *qmp_ringbuf_read(const char *device, uint64_t size,
 static void qemu_chr_parse_ringbuf(QemuOpts *opts, ChardevBackend *backend,
                                    Error **errp)
 {
-    int val;
     ChardevRingbuf *ringbuf;
 
     backend->type = CHARDEV_BACKEND_KIND_RINGBUF;
     ringbuf = backend->u.ringbuf.data = g_new0(ChardevRingbuf, 1);
     qemu_chr_parse_common(opts, qapi_ChardevRingbuf_base(ringbuf));
 
-    val = qemu_opt_get_size(opts, "size", 0);
-    if (val != 0) {
-        ringbuf->has_size = true;
-        ringbuf->size = val;
-    }
+    ringbuf->size = qemu_opt_get_size(opts, "size", 0);
+    ringbuf->has_size = ringbuf->size != 0;
 }
 
 static void char_ringbuf_class_init(ObjectClass *oc, void *data)
-- 
2.7.5