[PATCH 6.18.y] device property: initialize the remaining fields of fwnode_handle in fwnode_init()

[Sasha Levin <sashal@kernel.org>]

From: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

[ Upstream commit 7eba000621fff223dd7bab484d48918c7c77a307 ]

If a firmware node is allocated on the stack (for instance: temporary
software node whose life-time we control) or on the heap - but using a
non-zeroing allocation function - and initialized using fwnode_init(),
its secondary pointer will contain uninitialized memory which likely
will be neither NULL nor IS_ERR() and so may end up being dereferenced
(for example: in dev_to_swnode()). Set fwnode->secondary to NULL on
initialization. While at it: initialize the remaining fields of struct
fwnode_handle too just to be sure.

Cc: stable@vger.kernel.org
Fixes: 01bb86b380a3 ("driver core: Add fwnode_init()")
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Link: https://patch.msgid.link/20260511074927.9473-1-bartosz.golaszewski@oss.qualcomm.com
[ Fix typo in commit message. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/fwnode.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h
index 31df7608737e70..c30a9baafc0d99 100644
--- a/include/linux/fwnode.h
+++ b/include/linux/fwnode.h
@@ -210,8 +210,10 @@ static inline void fwnode_init(struct fwnode_handle *fwnode,
 {
 	fwnode->secondary = NULL;
 	fwnode->ops = ops;
+	fwnode->dev = NULL;
 	INIT_LIST_HEAD(&fwnode->consumers);
 	INIT_LIST_HEAD(&fwnode->suppliers);
+	fwnode->flags = 0;
 }
 
 static inline void fwnode_set_flag(struct fwnode_handle *fwnode,
-- 
2.53.0