[PATCH 04/18] software_node: Enforce parent before child ordering of nodes array for software_node_register_nodes()

Daniel Scally
2020-11-30T13:32:51Z

Registering software_nodes with the .parent member set to point to a
currently unregistered software_node has the potential for problems,
so enforce parent -> child ordering in arrays passed to this function.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Daniel Scally <djrscally@gmail.com>
---
Changes since RFC v3:

Patch introduced

drivers/base/swnode.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index 615a0c93e116..af7930b3679e 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -700,14 +700,21 @@ int software_node_register_nodes(const struct software_node *nodes)
int i;

for (i = 0; nodes[i].name; i++) {
+ if (nodes[i].parent)
+ if (!software_node_to_swnode(nodes[i].parent)) {
+ ret = -EINVAL;
+ goto err_unregister_nodes;
+ }
+
ret = software_node_register(&nodes[i]);
- if (ret) {
- software_node_unregister_nodes(nodes);
- return ret;
- }
+ if (ret)
+ goto err_unregister_nodes;
}

return 0;
+err_unregister_nodes:
+ software_node_unregister_nodes(nodes);
+ return ret;
}
EXPORT_SYMBOL_GPL(software_node_register_nodes);

--
2.25.1