The step variable is initialized to zero. It is changed in the loop,
but if it's not changed it will remain zero. Add a variable check
before the division.
The observed behavior was introduced by commit 826b5de90c0b
("ALSA: firewire-lib: fix insufficient PCM rule for period/buffer size"),
and it is difficult to show that any of the interval parameters will
satisfy the snd_interval_test() condition with data from the
amdtp_rate_table[] table.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 826b5de90c0b ("ALSA: firewire-lib: fix insufficient PCM rule for period/buffer size")
Signed-off-by: Andrey Shumilin <shum.sdl@xxxxxxxx>
---
sound/firewire/amdtp-stream.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index 4e2f2bb7879f..6c45ee3545f9 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -163,6 +163,9 @@ static int apply_constraint_to_size(struct snd_pcm_hw_params *params,
step = max(step, amdtp_syt_intervals[i]);
}
+ if (step == 0)
+ return -EINVAL;
+
t.min = roundup(s->min, step);
t.max = rounddown(s->max, step);
t.integer = 1;
--
2.30.2
