[pulseaudio-discuss] [PATCH v3 3/6] core-util: Make pa_parse_volume() more strict

[David Henningsson]

On 2015-04-27 13:34, Tanu Kaskinen wrote:
> Previously pa_parse_volume() clamped the value to fit in the valid
> range, but I think it's better to reject values outside the valid
> range.

It looks like pa_parse_volume is only used from module-role-ducking (via 
pa_modargs_get_value_volume) so I guess this should be okay without much 
regression risk.

Acked.

>
> This also changes the percentage parsing to allow non-integer values.
> ---
>   src/pulsecore/core-util.c | 42 ++++++++++++++++++++++++++----------------
>   1 file changed, 26 insertions(+), 16 deletions(-)
>
> diff --git a/src/pulsecore/core-util.c b/src/pulsecore/core-util.c
> index 4526306..ad5b2d2 100644
> --- a/src/pulsecore/core-util.c
> +++ b/src/pulsecore/core-util.c
> @@ -1008,7 +1008,7 @@ int pa_parse_boolean(const char *v) {
>   /* Try to parse a volume string to pa_volume_t. The allowed formats are:
>    * db, % and unsigned integer */
>   int pa_parse_volume(const char *v, pa_volume_t *volume) {
> -    int len, ret = -1;
> +    int len;
>       uint32_t i;
>       double d;
>       char str[64];
> @@ -1025,26 +1025,36 @@ int pa_parse_volume(const char *v, pa_volume_t *volume) {
>
>       if (str[len - 1] == '%') {
>           str[len - 1] = '\0';
> -        if (pa_atou(str, &i) == 0) {
> -            *volume = PA_CLAMP_VOLUME((uint64_t) PA_VOLUME_NORM * i / 100);
> -            ret = 0;
> -        }
> -    } else if (len > 2 && (str[len - 1] == 'b' || str[len - 1] == 'B') &&
> +        if (pa_atod(str, &d) < 0)
> +            return -1;
> +
> +        d = d / 100 * PA_VOLUME_NORM;
> +
> +        if (d < 0 || d > PA_VOLUME_MAX)
> +            return -1;
> +
> +        *volume = d;
> +        return 0;
> +    }
> +
> +    if (len > 2 && (str[len - 1] == 'b' || str[len - 1] == 'B') &&
>                  (str[len - 2] == 'd' || str[len - 2] == 'D')) {
>           str[len - 2] = '\0';
> -        if (pa_atod(str, &d) == 0) {
> -            *volume = pa_sw_volume_from_dB(d);
> -            ret = 0;
> -        }
> -    } else {
> -        if (pa_atou(v, &i) == 0) {
> -            *volume= PA_CLAMP_VOLUME(i);
> -            ret = 0;
> -        }
> +        if (pa_atod(str, &d) < 0)
> +            return -1;
> +
> +        if (d > pa_sw_volume_to_dB(PA_VOLUME_MAX))
> +            return -1;
>
> +        *volume = pa_sw_volume_from_dB(d);
> +        return 0;
>       }
>
> -    return ret;
> +    if (pa_atou(v, &i) < 0 || !PA_VOLUME_IS_VALID(i))
> +        return -1;
> +
> +    *volume = i;
> +    return 0;
>   }
>
>   /* Split the specified string wherever one of the strings in delimiter
>

-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic