From: Xu Biang xubiang@hust.edu.cn
commit fb4a624f88f658c7b7ae124452bd42eaa8ac7168 upstream.
Smatch Warns: sound/firewire/tascam/tascam-stream.c:493 snd_tscm_stream_start_duplex() warn: missing unwind goto?
The direct return will cause the stream list of "&tscm->domain" unemptied and the session in "tscm" unfinished if amdtp_domain_start() returns with an error.
Fix this by changing the direct return to a goto which will empty the stream list of "&tscm->domain" and finish the session in "tscm".
The snd_tscm_stream_start_duplex() function is called in the prepare callback of PCM. According to "ALSA Kernel API Documentation", the prepare callback of PCM will be called many times at each setup. So, if the "&d->streams" list is not emptied, when the prepare callback is called next time, snd_tscm_stream_start_duplex() will receive -EBUSY from amdtp_domain_add_stream() that tries to add an existing stream to the domain. The error handling code after the "error" label will be executed in this case, and the "&d->streams" list will be emptied. So not emptying the "&d->streams" list will not cause an issue. But it is more efficient and readable to empty it on the first error by changing the direct return to a goto statement.
The session in "tscm" has been begun before amdtp_domain_start(), so it needs to be finished when amdtp_domain_start() fails.
Fixes: c281d46a51e3 ("ALSA: firewire-tascam: support AMDTP domain") Signed-off-by: Xu Biang xubiang@hust.edu.cn Reviewed-by: Dan Carpenter error27@gmail.com Acked-by: Takashi Sakamoto o-takashi@sakamocchi.jp Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230406132801.105108-1-xubiang@hust.edu.cn Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- sound/firewire/tascam/tascam-stream.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/sound/firewire/tascam/tascam-stream.c +++ b/sound/firewire/tascam/tascam-stream.c @@ -490,7 +490,7 @@ int snd_tscm_stream_start_duplex(struct // packet is important for media clock recovery. err = amdtp_domain_start(&tscm->domain, tx_init_skip_cycles, true, true); if (err < 0) - return err; + goto error;
if (!amdtp_domain_wait_ready(&tscm->domain, READY_TIMEOUT_MS)) { err = -ETIMEDOUT;