From: Takashi Iwai <tiwai@suse.de>
To: alsa-devel@alsa-project.org
Cc: Kees Cook <keescook@chromium.org>, linux-kernel@vger.kernel.org
Subject: [PATCH] ALSA: pcm: Remove VLA usage
Date: Tue, 13 Mar 2018 12:37:58 +0100 [thread overview]
Message-ID: <20180313113758.14286-1-tiwai@suse.de> (raw)
A helper function used by snd_pcm_hw_refine() still keeps using VLA
for timestamps of hw constraint rules that are non-fixed size.
Let's replace the VLA with a simple kmalloc() array.
Reference: https://lkml.org/lkml/2018/3/7/621
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
sound/core/pcm_native.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 77ba50ddcf9e..756a9a3884a5 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -323,7 +323,7 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream,
struct snd_pcm_hw_constraints *constrs =
&substream->runtime->hw_constraints;
unsigned int k;
- unsigned int rstamps[constrs->rules_num];
+ unsigned int *rstamps;
unsigned int vstamps[SNDRV_PCM_HW_PARAM_LAST_INTERVAL + 1];
unsigned int stamp;
struct snd_pcm_hw_rule *r;
@@ -331,7 +331,7 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream,
struct snd_mask old_mask;
struct snd_interval old_interval;
bool again;
- int changed;
+ int changed, err = 0;
/*
* Each application of rule has own sequence number.
@@ -339,8 +339,9 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream,
* Each member of 'rstamps' array represents the sequence number of
* recent application of corresponding rule.
*/
- for (k = 0; k < constrs->rules_num; k++)
- rstamps[k] = 0;
+ rstamps = kcalloc(constrs->rules_num, sizeof(unsigned int), GFP_KERNEL);
+ if (!rstamps)
+ return -ENOMEM;
/*
* Each member of 'vstamps' array represents the sequence number of
@@ -398,8 +399,10 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream,
}
changed = r->func(params, r);
- if (changed < 0)
- return changed;
+ if (changed < 0) {
+ err = changed;
+ goto out;
+ }
/*
* When the parameter is changed, notify it to the caller
@@ -430,7 +433,9 @@ static int constrain_params_by_rules(struct snd_pcm_substream *substream,
if (again)
goto retry;
- return 0;
+ out:
+ kfree(rstamps);
+ return err;
}
static int fixup_unreferenced_params(struct snd_pcm_substream *substream,
--
2.16.2
next reply other threads:[~2018-03-13 11:38 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-13 11:37 Takashi Iwai [this message]
2018-03-13 13:59 ` [PATCH] ALSA: pcm: Remove VLA usage Takashi Sakamoto
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