ALSA: pcmtest: fix reference leak on failed device registration

When platform_device_register() fails in mod_init(), the embedded struct
device in pcmtst_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:

  mod_init()
    -> platform_device_register(&pcmtst_pdev)
       -> device_initialize(&pcmtst_pdev.dev)
       -> setup_pdev_dma_masks(&pcmtst_pdev)
       -> platform_device_add(&pcmtst_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: 315a3d57c64c5 ("ALSA: Implement the new Virtual PCM Test Driver")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Link: https://patch.msgid.link/20260415193138.3861297-1-lgs201920130244@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/drivers/pcmtest.c b/sound/drivers/pcmtest.c
index 768bb698adfb425db2d3ae3c5c11f66670328b9e..20ceb9082fa93f282f83907d6a76ac0f5c34a7f9 100644 (file)
--- a/sound/drivers/pcmtest.c
+++ b/sound/drivers/pcmtest.c
@@ -756,8 +756,10 @@ static int __init mod_init(void)
        if (err)
                return err;
        err = platform_device_register(&pcmtst_pdev);
-       if (err)
+       if (err) {
+               platform_device_put(&pcmtst_pdev);
                return err;
+       }
        err = platform_driver_register(&pcmtst_pdrv);
        if (err)
                platform_device_unregister(&pcmtst_pdev);