device property: initialize the remaining fields of fwnode_handle in fwnode_init()

[ Upstream commit 7eba000 ]

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: 01bb86b ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: brgl

include/linux/fwnode.h

@@ -195,8 +195,10 @@ 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,