staging: vchiq_arm: Fix missing refcount decrement in error path for fw_node

commit 22a3703af127e897dc7df89372b85bb9dc331c5f upstream.

An error path was introduced without including the required call to
of_node_put() to decrement the node's refcount and avoid leaking memory.
If the call to kzalloc() for 'mgmt' fails, the probe returns without
decrementing the refcount.

Use the automatic cleanup facility to fix the bug and protect the code
against new error paths where the call to of_node_put() might be missing
again.

Cc: stable@vger.kernel.org
Fixes: 1c9e16b73166 ("staging: vc04_services: vchiq_arm: Split driver static and runtime data")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20241014-vchiq_arm-of_node_put-v2-2-cafe0a4c2666@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
index 0ea1019b9edf6a018e8967ffff51b8a7930a0329..1e0d3d871fd41df492fc925864d0f3c1f694d631 100644 (file)
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
@@ -1715,7 +1715,6 @@ MODULE_DEVICE_TABLE(of, vchiq_of_match);
 
 static int vchiq_probe(struct platform_device *pdev)
 {
-       struct device_node *fw_node;
        const struct vchiq_platform_info *info;
        struct vchiq_drv_mgmt *mgmt;
        int ret;
@@ -1724,8 +1723,8 @@ static int vchiq_probe(struct platform_device *pdev)
        if (!info)
                return -EINVAL;
 
-       fw_node = of_find_compatible_node(NULL, NULL,
-                                         "raspberrypi,bcm2835-firmware");
+       struct device_node *fw_node __free(device_node) =
+               of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
        if (!fw_node) {
                dev_err(&pdev->dev, "Missing firmware node\n");
                return -ENOENT;
@@ -1736,7 +1735,6 @@ static int vchiq_probe(struct platform_device *pdev)
                return -ENOMEM;
 
        mgmt->fw = devm_rpi_firmware_get(&pdev->dev, fw_node);
-       of_node_put(fw_node);
        if (!mgmt->fw)
                return -EPROBE_DEFER;