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>
diff --git a/drivers/base/node.c b/drivers/base/node.c
index bc9f43b..8f7ed99 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -599,7 +599,11 @@
void unregister_one_node(int nid)
{
+ if (!node_devices[nid])
+ return;
+
unregister_node(node_devices[nid]);
+ kfree(node_devices[nid]);
node_devices[nid] = NULL;
}