ALSA: firewire-tascam: fix NULL pointer dereference when model identification fails

When unsupported models are connected, snd-firewire-tascam module causes
NULL pointer dereference in fw_core_remove_address_handler() (due to
list_del_rcu()).

This commit prevents this bug.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Sakamoto 2016-02-05 09:56:05 +09:00 committed by Takashi Iwai
parent 360a824568
commit 5d2560a427

View File

@ -230,6 +230,7 @@ int snd_tscm_transaction_register(struct snd_tscm *tscm)
return err;
error:
fw_core_remove_address_handler(&tscm->async_handler);
tscm->async_handler.callback_data = NULL;
return err;
}
@ -276,6 +277,9 @@ void snd_tscm_transaction_unregister(struct snd_tscm *tscm)
__be32 reg;
unsigned int i;
if (tscm->async_handler.callback_data == NULL)
return;
/* Turn off FireWire LED. */
reg = cpu_to_be32(0x0000008e);
snd_fw_transaction(tscm->unit, TCODE_WRITE_QUADLET_REQUEST,
@ -297,6 +301,8 @@ void snd_tscm_transaction_unregister(struct snd_tscm *tscm)
&reg, sizeof(reg), 0);
fw_core_remove_address_handler(&tscm->async_handler);
tscm->async_handler.callback_data = NULL;
for (i = 0; i < TSCM_MIDI_OUT_PORT_MAX; i++)
snd_fw_async_midi_port_destroy(&tscm->out_ports[i]);
}