ALSA: control: Re-order bounds checking in get_ctl_id_hash()
authorDan Carpenter <dan.carpenter@oracle.com>
Fri, 26 Aug 2022 15:01:10 +0000 (18:01 +0300)
committerTakashi Iwai <tiwai@suse.de>
Fri, 26 Aug 2022 15:17:22 +0000 (17:17 +0200)
These two checks are in the reverse order so it might read one element
beyond the end of the array.  First check if the "i" is within bounds
before using it.

Fixes: 6ab55ec0a938 ("ALSA: control: Fix an out-of-bounds bug in get_ctl_id_hash()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YwjgNh/gkG1hH7po@kili
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/core/control.c

index e8fc4c5..a727192 100644 (file)
@@ -391,7 +391,7 @@ static unsigned long get_ctl_id_hash(const struct snd_ctl_elem_id *id)
        h = id->iface;
        h = MULTIPLIER * h + id->device;
        h = MULTIPLIER * h + id->subdevice;
-       for (i = 0; id->name[i] && i < SNDRV_CTL_ELEM_ID_NAME_MAXLEN; i++)
+       for (i = 0; i < SNDRV_CTL_ELEM_ID_NAME_MAXLEN && id->name[i]; i++)
                h = MULTIPLIER * h + id->name[i];
        h = MULTIPLIER * h + id->index;
        h &= LONG_MAX;