* [PATCH] ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size()
@ 2024-10-18 6:00 Andrey Shumilin
2024-10-20 22:05 ` Takashi Sakamoto
2024-10-21 7:09 ` Takashi Iwai
0 siblings, 2 replies; 3+ messages in thread
From: Andrey Shumilin @ 2024-10-18 6:00 UTC (permalink / raw)
To: Clemens Ladisch, Takashi Sakamoto
Cc: Andrey Shumilin, Jaroslav Kysela, Takashi Iwai, alsa-devel,
linux-sound, linux-kernel, lvc-project, lvc-patches, khoroshilov,
ykarpov, vmerzlyakov, vefanov
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@nppct.ru>
---
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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size()
2024-10-18 6:00 [PATCH] ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size() Andrey Shumilin
@ 2024-10-20 22:05 ` Takashi Sakamoto
2024-10-21 7:09 ` Takashi Iwai
1 sibling, 0 replies; 3+ messages in thread
From: Takashi Sakamoto @ 2024-10-20 22:05 UTC (permalink / raw)
To: Andrey Shumilin
Cc: Takashi Iwai, linux-sound, lvc-project, lvc-patches, khoroshilov,
ykarpov, vmerzlyakov, vefanov
Hi,
On Fri, Oct 18, 2024 at 09:00:18AM +0300, Andrey Shumilin wrote:
> 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@nppct.ru>
> ---
> sound/firewire/amdtp-stream.c | 3 +++
> 1 file changed, 3 insertions(+)
I think it a good catch.
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Regards
Takashi Sakamoto
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size()
2024-10-18 6:00 [PATCH] ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size() Andrey Shumilin
2024-10-20 22:05 ` Takashi Sakamoto
@ 2024-10-21 7:09 ` Takashi Iwai
1 sibling, 0 replies; 3+ messages in thread
From: Takashi Iwai @ 2024-10-21 7:09 UTC (permalink / raw)
To: Andrey Shumilin
Cc: Clemens Ladisch, Takashi Sakamoto, Jaroslav Kysela, Takashi Iwai,
alsa-devel, linux-sound, linux-kernel, lvc-project, lvc-patches,
khoroshilov, ykarpov, vmerzlyakov, vefanov
On Fri, 18 Oct 2024 08:00:18 +0200,
Andrey Shumilin wrote:
>
> 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@nppct.ru>
Applied now. Thanks.
Takashi
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-10-21 7:08 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-10-18 6:00 [PATCH] ALSA: firewire-lib: Avoid division by zero in apply_constraint_to_size() Andrey Shumilin
2024-10-20 22:05 ` Takashi Sakamoto
2024-10-21 7:09 ` Takashi Iwai
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox