[alsa-devel] [PATCH 3/5] amixer: expand local storage for item name according to kernel code

[Takashi Iwai]

At Thu,  9 Apr 2015 01:30:56 +0900,
Takashi Sakamoto wrote:
> 
> According to kernel code (snd_ctl_elem_init_enum_names() in
> sound/core/control.c), the maximum length of item name is 63 characters
> (+ 1 terminator = 64 bytes). But current amixer implementation
> uses 40 bytes. This causes name truncation and fail to operation.
> 
> This commit fixes this bug by expanding the length of local variables.
> 
> Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>

Applied, thanks.


Takashi

> ---
>  amixer/amixer.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/amixer/amixer.c b/amixer/amixer.c
> index a3de375..65ebf20 100644
> --- a/amixer/amixer.c
> +++ b/amixer/amixer.c
> @@ -812,7 +812,11 @@ static int show_selem(snd_mixer_t *handle, snd_mixer_selem_id_t *id, const char
>  		if (snd_mixer_selem_is_enumerated(elem)) {
>  			int i, items;
>  			unsigned int idx;
> -			char itemname[40];
> +			/*
> +			 * See snd_ctl_elem_init_enum_names() in
> +			 * sound/core/control.c.
> +			 */
> +			char itemname[64];
>  			items = snd_mixer_selem_get_enum_items(elem);
>  			printf("  Items:");
>  			for (i = 0; i < items; i++) {
> @@ -1255,7 +1259,9 @@ static int get_enum_item_index(snd_mixer_elem_t *elem, char **ptrp)
>  {
>  	char *ptr = *ptrp;
>  	int items, i, len;
> -	char name[40];
> +
> +	/* See snd_ctl_elem_init_enum_names() in sound/core/control.c. */
> +	char name[64];
>  	
>  	items = snd_mixer_selem_get_enum_items(elem);
>  	if (items <= 0)
> @@ -1264,6 +1270,7 @@ static int get_enum_item_index(snd_mixer_elem_t *elem, char **ptrp)
>  	for (i = 0; i < items; i++) {
>  		if (snd_mixer_selem_get_enum_item_name(elem, i, sizeof(name)-1, name) < 0)
>  			continue;
> +
>  		len = strlen(name);
>  		if (! strncmp(name, ptr, len)) {
>  			if (! ptr[len] || ptr[len] == ',' || ptr[len] == '\n') {
> -- 
> 2.1.0
>