[PATCH] media: visl: fix reference leak on failed device registration

[Guangshuo Li]

When platform_device_register() fails in visl_init(), the embedded
struct device in visl_pdev has already been initialized by
device_initialize(), but the failure path returns the error without
dropping the device reference for the current platform device:

  visl_init()
    -> platform_device_register(&visl_pdev)
       -> device_initialize(&visl_pdev.dev)
       -> setup_pdev_dma_masks(&visl_pdev)
       -> platform_device_add(&visl_pdev)

This leads to a reference leak when platform_device_register() fails.
Fix this by calling platform_device_put() before returning the error.

The issue was identified by a static analysis tool I developed and
confirmed by manual review.

Fixes: 0c078e310b6d1 ("media: visl: add virtual stateless decoder driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
---
 drivers/media/test-drivers/visl/visl-core.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/media/test-drivers/visl/visl-core.c b/drivers/media/test-drivers/visl/visl-core.c
index 127ab18bce99..15e4f05d5ec9 100644
--- a/drivers/media/test-drivers/visl/visl-core.c
+++ b/drivers/media/test-drivers/visl/visl-core.c
@@ -558,8 +558,11 @@ static int __init visl_init(void)
 	int ret;
 
 	ret = platform_device_register(&visl_pdev);
-	if (ret)
+	if (ret) {
+		platform_device_put(&visl_pdev);
 		return ret;
+	}
+
 
 	ret = platform_driver_register(&visl_pdrv);
 	if (ret)
-- 
2.43.0