mtd: rawnand: atmel: fix OF child-node lookup

Use the new of_get_compatible_child() helper to lookup the nfc child
node instead of using of_find_compatible_node(), which searches the
entire tree from a given start node and thus can return an unrelated
(i.e. non-child) node.

This also addresses a potential use-after-free (e.g. after probe
deferral) as the tree-wide helper drops a reference to its first
argument (i.e. the node of the device being probed).

While at it, also fix a related nfc-node reference leak.

Fixes: f88fc122cc ("mtd: nand: Cleanup/rework the atmel_nand driver")
Cc: stable <stable@vger.kernel.org>     # 4.11
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Josh Wu <rainyfeeling@outlook.com>
Cc: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
This commit is contained in:
Johan Hovold 2018-08-27 10:21:49 +02:00 committed by Boris Brezillon
parent 1d5ceff25a
commit 5d1e9c2212

View File

@ -2032,8 +2032,7 @@ atmel_hsmc_nand_controller_legacy_init(struct atmel_hsmc_nand_controller *nc)
int ret;
nand_np = dev->of_node;
nfc_np = of_find_compatible_node(dev->of_node, NULL,
"atmel,sama5d3-nfc");
nfc_np = of_get_compatible_child(dev->of_node, "atmel,sama5d3-nfc");
if (!nfc_np) {
dev_err(dev, "Could not find device node for sama5d3-nfc\n");
return -ENODEV;
@ -2447,15 +2446,19 @@ static int atmel_nand_controller_probe(struct platform_device *pdev)
}
if (caps->legacy_of_bindings) {
struct device_node *nfc_node;
u32 ale_offs = 21;
/*
* If we are parsing legacy DT props and the DT contains a
* valid NFC node, forward the request to the sama5 logic.
*/
if (of_find_compatible_node(pdev->dev.of_node, NULL,
"atmel,sama5d3-nfc"))
nfc_node = of_get_compatible_child(pdev->dev.of_node,
"atmel,sama5d3-nfc");
if (nfc_node) {
caps = &atmel_sama5_nand_caps;
of_node_put(nfc_node);
}
/*
* Even if the compatible says we are dealing with an