On Sat, Nov 10, 2018 at 06:02:41PM -0800, Greg Kroah-Hartman wrote:
>
> The patch below does not apply to the 4.9-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@xxxxxxxxxxxxxxx>.
This one also depends on
36156f9241cb ("of: add helper to lookup compatible child node")
Johan
> ------------------ original commit in Linus's tree ------------------
>
> From 9844fb2e351311210e6660a9a1c62d17424a6145 Mon Sep 17 00:00:00 2001
> From: Johan Hovold <johan@xxxxxxxxxx>
> Date: Mon, 27 Aug 2018 10:21:53 +0200
> Subject: [PATCH] power: supply: twl4030-charger: fix OF sibling-node lookup
>
> 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>
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
>
> 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)
>
