From: Geert Uytterhoeven geert+renesas@glider.be
commit 9f65df9c589f249435255da37a5dd11f1bc86f4d upstream.
As snd_fw_async_midi_port.consume_bytes is unsigned int, and NSEC_PER_SEC is 1000000000L, the second multiplication in
port->consume_bytes * 8 * NSEC_PER_SEC / 31250
always overflows on 32-bit platforms, truncating the result. Fix this by precalculating "NSEC_PER_SEC / 31250", which is an integer constant.
Note that this assumes port->consume_bytes <= 16777.
Fixes: 531f471834227d03 ("ALSA: firewire-lib/firewire-tascam: localize async midi port") Reviewed-by: Takashi Sakamoto o-takashi@sakamocchi.jp Signed-off-by: Geert Uytterhoeven geert+renesas@glider.be Link: https://lore.kernel.org/r/20210111130251.361335-3-geert+renesas@glider.be Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- sound/firewire/tascam/tascam-transaction.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/firewire/tascam/tascam-transaction.c b/sound/firewire/tascam/tascam-transaction.c index 2ad692dd4b137..92f7e74d58478 100644 --- a/sound/firewire/tascam/tascam-transaction.c +++ b/sound/firewire/tascam/tascam-transaction.c @@ -210,7 +210,7 @@ static void midi_port_work(struct work_struct *work)
/* Set interval to next transaction. */ port->next_ktime = ktime_add_ns(ktime_get(), - port->consume_bytes * 8 * NSEC_PER_SEC / 31250); + port->consume_bytes * 8 * (NSEC_PER_SEC / 31250));
/* Start this transaction. */ port->idling = false;