From: Stephen Hemminger stephen@networkplumber.org
For unsupported device types, the vmbus channel ringbuffer is never initialized, and therefore reading the sysfs files will return garbage or cause a kernel OOPS.
Fixes: c2e5df616e1a ("vmbus: add per-channel sysfs info")
Signed-off-by: Stephen Hemminger sthemmin@microsoft.com Signed-off-by: K. Y. Srinivasan kys@microsoft.com Cc: stable@vger.kernel.org # 4.15 --- drivers/hv/vmbus_drv.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index e6d8fdac6d8b..4bbc420d1213 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1368,6 +1368,9 @@ static ssize_t vmbus_chan_attr_show(struct kobject *kobj, if (!attribute->show) return -EIO;
+ if (chan->state != CHANNEL_OPENED_STATE) + return -EINVAL; + return attribute->show(chan, buf); }