power: supply: twl4030-charger: fix OF sibling-node lookup

jhovold · robherring · commit 9844fb2e3513 · 2018-10-23T13:28:53.000-05:00
Use the new of_get_compatible_child() helper to lookup the usb sibling node instead of using of_find_compatible_node(), which searches the entire tree from a given start node and thus can return an unrelated (non-sibling) 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 parent device node). While at it, also fix the related phy-node reference leak. Fixes: f5e4edb ("power: twl4030_charger: find associated phy by more reliable means.") Cc: stable <stable@vger.kernel.org> # 4.2 Cc: NeilBrown <neilb@suse.de> Cc: Felipe Balbi <felipe.balbi@linux.intel.com> Cc: Sebastian Reichel <sre@kernel.org> Reviewed-by: Sebastian Reichel <sre@kernel.org> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Rob Herring <robh@kernel.org>
diff --git a/drivers/power/supply/twl4030_charger.c b/drivers/power/supply/twl4030_charger.c
@@ -996,12 +996,13 @@ static int twl4030_bci_probe(struct platform_device *pdev)
 	if (bci->dev->of_node) {
 		struct device_node *phynode;
 
-		phynode = of_find_compatible_node(bci->dev->of_node->parent,
-						  NULL, "ti,twl4030-usb");
+		phynode = of_get_compatible_child(bci->dev->of_node->parent,
+						  "ti,twl4030-usb");
 		if (phynode) {
 			bci->usb_nb.notifier_call = twl4030_bci_usb_ncb;
 			bci->transceiver = devm_usb_get_phy_by_node(
 				bci->dev, phynode, &bci->usb_nb);
+			of_node_put(phynode);
 			if (IS_ERR(bci->transceiver)) {
 				ret = PTR_ERR(bci->transceiver);
 				if (ret == -EPROBE_DEFER)
