ALSA: hwdep: prevent a harmless shift wrapping bug

The "info.index" variable represents a bit in hw->dsp_loaded which is
an unsigned int.  If it's higher than 31 we hit a shift wrapping bug.
This seems harmless, but I wanted to silence the static checker warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Dan Carpenter 2017-09-14 02:01:16 +03:00 committed by Takashi Iwai
parent 2bd6bf03f4
commit c4fd43793b

View File

@ -228,6 +228,8 @@ static int snd_hwdep_dsp_load(struct snd_hwdep *hw,
memset(&info, 0, sizeof(info));
if (copy_from_user(&info, _info, sizeof(info)))
return -EFAULT;
if (info.index >= 32)
return -EINVAL;
/* check whether the dsp was already loaded */
if (hw->dsp_loaded & (1 << info.index))
return -EBUSY;