[PATCH v2 9/9] power: supply: twl4030-charger: fix OF sibling-node lookup

From: Johan Hovold
Date: Mon Aug 27 2018 - 04:22:43 EST

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: f5e4edb8c888 ("power: twl4030_charger: find associated phy by more reliable means.")
Cc: stable <stable@xxxxxxxxxxxxxxx> # 4.2
Cc: NeilBrown <neilb@xxxxxxx>
Cc: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Cc: Sebastian Reichel <sre@xxxxxxxxxx>
Reviewed-by: Sebastian Reichel <sre@xxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
drivers/power/supply/twl4030_charger.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/power/supply/twl4030_charger.c b/drivers/power/supply/twl4030_charger.c
index bbcaee56db9d..b6a7d9f74cf3 100644
--- 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)