[PATCH v2] driver core: cpu: Fix OF node reference leak in register_cpu() error path

[Wentao Liang]

register_cpu() stores the reference from of_get_cpu_node() in
cpu->dev.of_node, but does not release it if device_register() fails.

Drop the reference on failure and clear the pointer, since architecture
code such as PPC's register_cpu_online() checks it for NULL before
obtaining a node reference.

Fixes: f86e4718f24b ("driver/core: cpu: initialize of_node in cpu's device struture")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
---
Changes in v2:
- Clear cpu->dev.of_node after of_node_put(), as Sudeep requested.
- Drop the series numbering. This is an independent fix and does not
  belong to a series with the other patches posted alongside it.
  That is a submission mistake on my side. Sorry for the delayed reply,
  the submission error, and the extra review work this caused.

 drivers/base/cpu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 875abdc9942e..b50ba6a32a3a 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -431,6 +431,8 @@ int register_cpu(struct cpu *cpu, int num)
 	error = device_register(&cpu->dev);
 	if (error) {
 		put_device(&cpu->dev);
+		of_node_put(cpu->dev.of_node);
+		cpu->dev.of_node = NULL;
 		return error;
 	}
 
-- 
2.34.1