Re: [PATCH] ALSA: control: Fix power refcount leak in snd_ctl_elem_read_user

[Takashi Iwai]

On Fri, 12 Jun 2026 04:27:02 +0200,
WenTao Liang wrote:
> 
> snd_power_ref_and_wait() increments the power refcount before waiting.
> When it returns an error (e.g., -ENODEV due to card shutdown), the
> refcount is still held, as documented in its comment:
> 
>   "The caller needs to pull down the refcount via snd_power_unref()
>    later no matter whether the error is returned from this function
>    or not."
> 
> snd_ctl_elem_read_user() fails to release this refcount on the error
> path, leaking a reference. This can impede proper card resource
> cleanup during shutdown sequences.
> 
> Fix by calling snd_power_unref() before returning the error.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: fcc62b19104a ("ALSA: control: Take power_ref lock primarily")
> Signed-off-by: WenTao Liang <vulab@xxxxxxxxxxx>

Your all other patches for sound/core/* look like similar fixes, and
should be better put in a single fix patch.  If need to split to
multiple patches, though, please send a series of patches in a thread,
instead, at the next time.


thanks,

Takashi