[alsa-devel] [PATCH v2] ALSA: control: Add sanity checks for user ctl id name string

[Takashi Sakamoto]

Iwai-san,

On Mar 12 2015 15:41, Takashi Iwai wrote:
> There was no check about the id string of user control elements, so we
> accepted even a control element with an empty string, which is
> obviously bogus.  This patch adds more sanity checks of id strings.
>
> Cc: <stable at vger.kernel.org>
> Signed-off-by: Takashi Iwai <tiwai at suse.de>
> ---
> v1->v2: fix typos, thinkos
>
>   sound/core/control.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/sound/core/control.c b/sound/core/control.c
> index 35324a8e83c8..eeb691d1911f 100644
> --- a/sound/core/control.c
> +++ b/sound/core/control.c
> @@ -1170,6 +1170,10 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file,
>
>   	if (info->count < 1)
>   		return -EINVAL;
> +	if (!*info->id.name)
> +		return -EINVAL;
> +	if (strnlen(info->id.name, sizeof(info->id.name)) >= sizeof(info->id.name))
> +		return -EINVAL;

Over 80 characters.

$ ./scripts/checkpatch.pl /tmp/patches/*
WARNING: line over 80 characters
#25: FILE: sound/core/control.c:1019:
+	if (strnlen(info->id.name, sizeof(info->id.name)) >= 
sizeof(info->id.name))

total: 0 errors, 1 warnings, 10 lines checked

>   	access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :
>   		(info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|
>   				 SNDRV_CTL_ELEM_ACCESS_INACTIVE|


Regards

Takashi Sakamoto