ALSA: hda - Check strcpy length

Check the length to copy via strlen() beforehand to avoid the stack
corruption, or use strlcpy() to be safe in HD-audio codes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_codec.c

@@ -1431,6 +1431,8 @@ _snd_hda_find_mixer_ctl(struct hda_codec *codec,
 	memset(&id, 0, sizeof(id));
 	id.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 	id.index = idx;
+	if (snd_BUG_ON(strlen(name) >= sizeof(id.name)))
+		return NULL;
 	strcpy(id.name, name);
 	return snd_ctl_find_id(codec->bus->card, &id);
 }

sound/pci/hda/hda_intel.c

@@ -1830,7 +1830,7 @@ azx_attach_pcm_stream(struct hda_bus *bus, struct hda_codec *codec,
 			  &pcm);
 	if (err < 0)
 		return err;
-	strcpy(pcm->name, cpcm->name);
+	strlcpy(pcm->name, cpcm->name, sizeof(pcm->name));
 	apcm = kzalloc(sizeof(*apcm), GFP_KERNEL);
 	if (apcm == NULL)
 		return -ENOMEM;
@@ -2358,9 +2358,11 @@ static int __devinit azx_create(struct snd_card *card, struct pci_dev *pci,
 	}
 
 	strcpy(card->driver, "HDA-Intel");
-	strcpy(card->shortname, driver_short_names[chip->driver_type]);
-	sprintf(card->longname, "%s at 0x%lx irq %i",
-		card->shortname, chip->addr, chip->irq);
+	strlcpy(card->shortname, driver_short_names[chip->driver_type],
+		sizeof(card->shortname));
+	snprintf(card->longname, sizeof(card->longname),
+		 "%s at 0x%lx irq %i",
+		 card->shortname, chip->addr, chip->irq);
 
 	*rchip = chip;
 	return 0;