linux-kernel - Fwd: [PATCH 1/1] staging/speakup/kobjects.c: Code improvement.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Mon, 9 Sep 2013 01:16:51 -0300
From:	Raphael S Carvalho <raphael.scarv@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: Fwd: [PATCH 1/1] staging/speakup/kobjects.c: Code improvement.

On Mon, Sep 9, 2013 at 12:56 AM, Chris Brannon <chris@...-brannons.com> wrote:
>
> "Raphael S.Carvalho" <raphael.scarv@...il.com> writes:
>
> > +             /*
> > +             * If voice was just changed, we might need to reset our default
> > +             * pitch and volume.
> > +             */
> > +             if (param->var_id == VOICE) {
> > +                     spk_reset_default_value("pitch", synth->default_pitch,
> > +                             value);
> > +                     spk_reset_default_value("vol", synth->default_vol,
> > +                             value);
>
> There's an "invalid read" bug here.  You didn't introduce it; it has
> been there all along.  It's possible that value contains a value that is
> out of range, in which case, the spk_reset_default_value calls could
> fetch invalid data.  The value of ret should be sufficient for
> determining whether value is in range, so I'd change the condition of
> the if statement to this:


Wouldn't the following code (right before the statement: if
(param->var_id == VOICE))
check if value is out of range?

        value = simple_strtol(cp, NULL, 10);
        ret = spk_set_num_var(value, param, len);

        if (ret == -ERANGE) {
            var_data = param->data;
            pr_warn("value for %s out of range, expect %d to %d\n",
                param->name,
                var_data->u.n.low, var_data->u.n.high);
        }

>
>
>                 if (param->var_id == VOICE && ret != -ERANGE) {
>
> Or possibly better:
>                 if (param->var_id == VOICE && ret == 0) {
>
> I'd say please resend with that fix, or if not, I can send a one-line
> patch to be applied after yours.
>
> -- Chris


Regards,
Raphael S. Carvalho
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/