[PATCH v5 05/21] nvmem: core: fix device node refcounting

Michael Walle
2022-12-06T20:10:22Z

In of_nvmem_cell_get(), of_get_next_parent() is used on cell_np. This
will decrement the refcount on cell_np, but cell_np is still used later
in the code. Use of_get_parent() instead and of_node_put() in the
appropriate places.

Signed-off-by: Michael Walle <michael@walle.cc>
---
changes since v4:
- none

changes since v3:
- none

changes since v2:
- new patch

drivers/nvmem/core.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 321d7d63e068..205a427f564d 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -1242,16 +1242,21 @@ struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id)
if (!cell_np)
return ERR_PTR(-ENOENT);

- nvmem_np = of_get_next_parent(cell_np);
- if (!nvmem_np)
+ nvmem_np = of_get_parent(cell_np);
+ if (!nvmem_np) {
+ of_node_put(cell_np);
return ERR_PTR(-EINVAL);
+ }

nvmem = __nvmem_device_get(nvmem_np, device_match_of_node);
of_node_put(nvmem_np);
- if (IS_ERR(nvmem))
+ if (IS_ERR(nvmem)) {
+ of_node_put(cell_np);
return ERR_CAST(nvmem);
+ }

cell_entry = nvmem_find_cell_entry_by_node(nvmem, cell_np);
+ of_node_put(cell_np);
if (!cell_entry) {
__nvmem_device_put(nvmem);
return ERR_PTR(-ENOENT);