From 5c1c9bb24b20fb5844d01ac67d51c26941db5af1 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Tue, 19 Apr 2011 12:03:46 +1000 Subject: [PATCH] virtio-serial: Fix endianness bug in the config space The virtio serial specification requres that the values in the config space are encoded in native endian of the guest. The qemu virtio-serial code did not do conversion to the guest endian format what caused problems when host and guest use different format. This patch corrects the qemu side, correctly doing host-native <-> guest-native conversions when accessing the config space. This won't break any setups that aren't already broken, and fixes the case of different host and guest endianness. Signed-off-by: Alexey Kardashevskiy Signed-off-by: David Gibson Reviewed-by: Juan Quintela Signed-off-by: Amit Shah --- hw/virtio-serial-bus.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/hw/virtio-serial-bus.c b/hw/virtio-serial-bus.c index 62273799b6..f10d48fdb0 100644 --- a/hw/virtio-serial-bus.c +++ b/hw/virtio-serial-bus.c @@ -494,7 +494,7 @@ static void virtio_serial_save(QEMUFile *f, void *opaque) VirtIOSerial *s = opaque; VirtIOSerialPort *port; uint32_t nr_active_ports; - unsigned int i; + unsigned int i, max_nr_ports; /* The virtio device */ virtio_save(&s->vdev, f); @@ -506,8 +506,8 @@ static void virtio_serial_save(QEMUFile *f, void *opaque) qemu_put_be32s(f, &s->config.max_nr_ports); /* The ports map */ - - for (i = 0; i < (s->config.max_nr_ports + 31) / 32; i++) { + max_nr_ports = tswap32(s->config.max_nr_ports); + for (i = 0; i < (max_nr_ports + 31) / 32; i++) { qemu_put_be32s(f, &s->ports_map[i]); } @@ -568,7 +568,8 @@ static int virtio_serial_load(QEMUFile *f, void *opaque, int version_id) qemu_get_be16s(f, &s->config.rows); qemu_get_be32s(f, &max_nr_ports); - if (max_nr_ports > s->config.max_nr_ports) { + tswap32s(&max_nr_ports); + if (max_nr_ports > tswap32(s->config.max_nr_ports)) { /* Source could have had more ports than us. Fail migration. */ return -EINVAL; } @@ -670,9 +671,10 @@ static void virtser_bus_dev_print(Monitor *mon, DeviceState *qdev, int indent) /* This function is only used if a port id is not provided by the user */ static uint32_t find_free_port_id(VirtIOSerial *vser) { - unsigned int i; + unsigned int i, max_nr_ports; - for (i = 0; i < (vser->config.max_nr_ports + 31) / 32; i++) { + max_nr_ports = tswap32(vser->config.max_nr_ports); + for (i = 0; i < (max_nr_ports + 31) / 32; i++) { uint32_t map, bit; map = vser->ports_map[i]; @@ -720,7 +722,7 @@ static int virtser_port_qdev_init(DeviceState *qdev, DeviceInfo *base) VirtIOSerialPort *port = DO_UPCAST(VirtIOSerialPort, dev, qdev); VirtIOSerialPortInfo *info = DO_UPCAST(VirtIOSerialPortInfo, qdev, base); VirtIOSerialBus *bus = DO_UPCAST(VirtIOSerialBus, qbus, qdev->parent_bus); - int ret; + int ret, max_nr_ports; bool plugging_port0; port->vser = bus->vser; @@ -750,9 +752,10 @@ static int virtser_port_qdev_init(DeviceState *qdev, DeviceInfo *base) } } - if (port->id >= port->vser->config.max_nr_ports) { + max_nr_ports = tswap32(port->vser->config.max_nr_ports); + if (port->id >= max_nr_ports) { error_report("virtio-serial-bus: Out-of-range port id specified, max. allowed: %u\n", - port->vser->config.max_nr_ports - 1); + max_nr_ports - 1); return -1; } @@ -863,7 +866,7 @@ VirtIODevice *virtio_serial_init(DeviceState *dev, virtio_serial_conf *conf) vser->ovqs[i] = virtio_add_queue(vdev, 128, handle_output); } - vser->config.max_nr_ports = conf->max_virtserial_ports; + vser->config.max_nr_ports = tswap32(conf->max_virtserial_ports); vser->ports_map = qemu_mallocz(((conf->max_virtserial_ports + 31) / 32) * sizeof(vser->ports_map[0])); /* -- 2.11.4.GIT