diff options
| author | Luiz Capitulino <lcapitulino@redhat.com> | 2013-04-18 11:53:32 -0400 |
|---|---|---|
| committer | Luiz Capitulino <lcapitulino@redhat.com> | 2013-04-19 08:32:44 -0400 |
| commit | dcc6ceffc066745777960a1f0d32f3a555924f65 (patch) | |
| tree | 5ecaf08ef3f85376848d1cf17a4d1c5c63079969 | |
| parent | 153d02e338a063ad5c51ff0725d5d88285f44121 (diff) | |
virtio-balloon: fix integer overflow in BALLOON_CHANGE QMP event
Because dev->actual is uint32_t, the expression 'dev->actual <<
VIRTIO_BALLOON_PFN_SHIFT' is truncated to 32 bits. This overflows when
dev->actual >= 1048576.
To reproduce:
1. Start a VM with a QMP socket and 5G of RAM
2. Connect to the QMP socket, negotiate capabilities and issue:
{ "execute":"balloon", "arguments": { "value": 1073741824 } }
3. Watch for BALLOON_CHANGE QMP events, the last one will incorretly be:
{ "timestamp": { "seconds": 1366228965, "microseconds": 245466 },
"event": "BALLOON_CHANGE", "data": { "actual": 5368709120 } }
To fix it this commit casts it to ram_addr_t, which is ram_size's type.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
| -rw-r--r-- | hw/virtio/virtio-balloon.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index c2c446eb9b..76e32ceef8 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -275,7 +275,7 @@ static void virtio_balloon_set_config(VirtIODevice *vdev, dev->actual = le32_to_cpu(config.actual); if (dev->actual != oldactual) { qemu_balloon_changed(ram_size - - (dev->actual << VIRTIO_BALLOON_PFN_SHIFT)); + ((ram_addr_t) dev->actual << VIRTIO_BALLOON_PFN_SHIFT)); } } |