[PATCH 4.15 044/128] USB: ledtrig-usbport: fix of-node leak

Greg Kroah-Hartman
2018-03-16T15:23:05Z

From: Johan Hovold <johan@kernel.org>

[ Upstream commit 03310a15484ab6a8f6d91bbf7fe486b17275c09a ]

This code looks up a USB device node from a given parent USB device but
never dropped its reference to the returned node.

As only the address of the node is used for a later matching, the
reference can be dropped immediately.

Note that this trigger implementation confuses the description of the
USB device connected to a port with the port itself (which does not have
a device-tree representation).

Fixes: 4f04c210d031 ("usb: core: read USB ports from DT in the usbport LED trigger driver")
Cc: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/core/ledtrig-usbport.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/usb/core/ledtrig-usbport.c
+++ b/drivers/usb/core/ledtrig-usbport.c
@@ -137,11 +137,17 @@ static bool usbport_trig_port_observed(s
if (!led_np)
return false;

- /* Get node of port being added */
+ /*
+ * Get node of port being added
+ *
+ * FIXME: This is really the device node of the connected device
+ */
port_np = usb_of_get_child_node(usb_dev->dev.of_node, port1);
if (!port_np)
return false;

+ of_node_put(port_np);
+
/* Amount of trigger sources for this LED */
count = of_count_phandle_with_args(led_np, "trigger-sources",
"#trigger-source-cells");