numa: fix NULL pointer access and memory leak in unregister_one_node()

When doing socket hot remove, "node_devices[nid]" is set to NULL;
acpi_processor_remove()
	try_offline_node()
		unregister_one_node()

Then hot add a socket, but do not echo 1 > /sys/devices/system/cpu/cpuXX/online,
so register_one_node() will not be called, and "node_devices[nid]"
is still NULL.

If doing socket hot remove again, NULL pointer access will be happen.
unregister_one_node()
	unregister_node()

Another, we should free the memory used by "node_devices[nid]" in
unregister_one_node().

Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Xishi Qiu 2014-03-06 17:18:21 +08:00 коммит произвёл Greg Kroah-Hartman
Родитель aa0689b36b
Коммит 92d585ef06
1 изменённых файлов: 4 добавлений и 0 удалений

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@ -599,7 +599,11 @@ int register_one_node(int nid)
void unregister_one_node(int nid)
{
if (!node_devices[nid])
return;
unregister_node(node_devices[nid]);
kfree(node_devices[nid]);
node_devices[nid] = NULL;
}