[PATCH 6.18 154/227] of: fix reference count leak in of_alias_scan()

Greg Kroah-Hartman
2026-01-28T15:58:44Z

From: Weigang He <geoffreyhe2@gmail.com>

commit 81122fba08fa3ccafab6ed272a5c6f2203923a7e upstream.

of_find_node_by_path() returns a device_node with its refcount
incremented. When kstrtoint() fails or dt_alloc() fails, the function
continues to the next iteration without calling of_node_put(), causing
a reference count leak.

Add of_node_put(np) before continue on both error paths to properly
release the device_node reference.

Fixes: 611cad720148 ("dt: add of_alias_scan and of_alias_get_id")
Cc: stable@vger.kernel.org
Signed-off-by: Weigang He <geoffreyhe2@gmail.com>
Link: https://patch.msgid.link/20260117091238.481243-1-geoffreyhe2@gmail.com
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/of/base.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1895,13 +1895,17 @@ void of_alias_scan(void * (*dt_alloc)(u6
end--;
len = end - start;

- if (kstrtoint(end, 10, &id) < 0)
+ if (kstrtoint(end, 10, &id) < 0) {
+ of_node_put(np);
continue;
+ }

/* Allocate an alias_prop with enough space for the stem */
ap = dt_alloc(sizeof(*ap) + len + 1, __alignof__(*ap));
- if (!ap)
+ if (!ap) {
+ of_node_put(np);
continue;
+ }
memset(ap, 0, sizeof(*ap) + len + 1);
ap->alias = start;
of_alias_add(ap, np, id, start, len);