[PATCH] ASoC: rsnd: fix usrcnt decrementing bug

[PATCH] ASoC: rsnd: fix usrcnt decrementing bug

[Andrzej Hajda]

Field usrcnt is unsigned so it cannot be lesser than zero.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
 sound/soc/sh/rcar/ssi.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
index 0b91692..8ca30fd 100644
--- a/sound/soc/sh/rcar/ssi.c
+++ b/sound/soc/sh/rcar/ssi.c
@@ -381,9 +381,9 @@ rsnd_ssi_quit_end:
 
 	rsnd_mod_power_off(mod);
 
-	ssi->usrcnt--;
-
-	if (ssi->usrcnt < 0)
+	if (ssi->usrcnt > 0)
+		ssi->usrcnt--;
+	else
 		dev_err(dev, "%s[%d] usrcnt error\n",
 			rsnd_mod_name(mod), rsnd_mod_id(mod));
 
-- 
1.9.1

Re: [PATCH] ASoC: rsnd: fix usrcnt decrementing bug

[Kuninori Morimoto]

Hi Andrzej

> Field usrcnt is unsigned so it cannot be lesser than zero.
> 
> The problem has been detected using proposed semantic patch
> scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].
> 
> [1]: http://permalink.gmane.org/gmane.linux.kernel/2038576
> 
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> ---

Thank you for your patch. good catch !
I noticed current error case is not good for ssi.c
Can you agree below ?

---------
diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
index 7db05fd..e519e30 100644
--- a/sound/soc/sh/rcar/ssi.c
+++ b/sound/soc/sh/rcar/ssi.c
@@ -403,6 +403,12 @@ static int rsnd_ssi_quit(struct rsnd_mod *mod,
 	struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
 	struct device *dev = rsnd_priv_to_dev(priv);
 
+	if (!ssi->usrcnt) {
+		dev_err(dev, "%s[%d] usrcnt error\n",
+			rsnd_mod_name(mod), rsnd_mod_id(mod));
+		return -EIO;
+	}
+
 	if (rsnd_ssi_is_parent(mod, io))
 		goto rsnd_ssi_quit_end;
 
@@ -422,10 +428,6 @@ rsnd_ssi_quit_end:
 
 	ssi->usrcnt--;
 
-	if (ssi->usrcnt < 0)
-		dev_err(dev, "%s[%d] usrcnt error\n",
-			rsnd_mod_name(mod), rsnd_mod_id(mod));
-
 	return 0;
 }
 
---------


Best regards
---
Kuninori Morimoto

Re: [PATCH] ASoC: rsnd: fix usrcnt decrementing bug

[Andrzej Hajda]

On 12/24/2015 01:04 AM, Kuninori Morimoto wrote:
> Hi Andrzej
>
>> Field usrcnt is unsigned so it cannot be lesser than zero.
>>
>> The problem has been detected using proposed semantic patch
>> scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].
>>
>> [1]: http://permalink.gmane.org/gmane.linux.kernel/2038576
>>
>> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
>> ---
> Thank you for your patch. good catch !
> I noticed current error case is not good for ssi.c
> Can you agree below ?
Yes, of course.

Regards
Andrzej
>
> ---------
> diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
> index 7db05fd..e519e30 100644
> --- a/sound/soc/sh/rcar/ssi.c
> +++ b/sound/soc/sh/rcar/ssi.c
> @@ -403,6 +403,12 @@ static int rsnd_ssi_quit(struct rsnd_mod *mod,
>  	struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
>  	struct device *dev = rsnd_priv_to_dev(priv);
>  
> +	if (!ssi->usrcnt) {
> +		dev_err(dev, "%s[%d] usrcnt error\n",
> +			rsnd_mod_name(mod), rsnd_mod_id(mod));
> +		return -EIO;
> +	}
> +
>  	if (rsnd_ssi_is_parent(mod, io))
>  		goto rsnd_ssi_quit_end;
>  
> @@ -422,10 +428,6 @@ rsnd_ssi_quit_end:
>  
>  	ssi->usrcnt--;
>  
> -	if (ssi->usrcnt < 0)
> -		dev_err(dev, "%s[%d] usrcnt error\n",
> -			rsnd_mod_name(mod), rsnd_mod_id(mod));
> -
>  	return 0;
>  }
>  
> ---------
>
>
> Best regards
> ---
> Kuninori Morimoto
>
>

Re: [PATCH] ASoC: rsnd: fix usrcnt decrementing bug

[Kuninori Morimoto]

Hi Andrzej

> >> Field usrcnt is unsigned so it cannot be lesser than zero.
> >>
> >> The problem has been detected using proposed semantic patch
> >> scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].
> >>
> >> [1]: http://permalink.gmane.org/gmane.linux.kernel/2038576
> >>
> >> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> >> ---
> > Thank you for your patch. good catch !
> > I noticed current error case is not good for ssi.c
> > Can you agree below ?
> Yes, of course.

Thanks.
Who send this patch ? you or me ?
I think you can do it ?

[PATCH v2] ASoC: rsnd: fix usrcnt decrementing bug

[Andrzej Hajda]

Field usrcnt is unsigned so it cannot be lesser than zero.
The patch fixes the check, moves it to the beginning of the function
and changes return value to -EIO in case of usercnt error.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
---
v2: changed according to Kuninori Morimoto advice
---
 sound/soc/sh/rcar/ssi.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
index 0b91692..f23c921 100644
--- a/sound/soc/sh/rcar/ssi.c
+++ b/sound/soc/sh/rcar/ssi.c
@@ -364,29 +364,30 @@ static int rsnd_ssi_quit(struct rsnd_mod *mod,
 	struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
 	struct device *dev = rsnd_priv_to_dev(priv);
 
-	if (rsnd_ssi_is_parent(mod, io))
-		goto rsnd_ssi_quit_end;
+	if (!ssi->usrcnt) {
+		dev_err(dev, "%s[%d] usrcnt error\n",
+			rsnd_mod_name(mod), rsnd_mod_id(mod));
+		return -EIO;
+	}
 
-	if (ssi->err > 0)
-		dev_warn(dev, "%s[%d] under/over flow err = %d\n",
-			 rsnd_mod_name(mod), rsnd_mod_id(mod), ssi->err);
+	if (!rsnd_ssi_is_parent(mod, io)) {
+		if (ssi->err > 0)
+			dev_warn(dev, "%s[%d] under/over flow err = %d\n",
+				 rsnd_mod_name(mod), rsnd_mod_id(mod),
+				 ssi->err);
 
-	ssi->cr_own	= 0;
-	ssi->err	= 0;
+		ssi->cr_own	= 0;
+		ssi->err	= 0;
 
-	rsnd_ssi_irq_disable(mod);
+		rsnd_ssi_irq_disable(mod);
+	}
 
-rsnd_ssi_quit_end:
 	rsnd_ssi_master_clk_stop(ssi, io);
 
 	rsnd_mod_power_off(mod);
 
 	ssi->usrcnt--;
 
-	if (ssi->usrcnt < 0)
-		dev_err(dev, "%s[%d] usrcnt error\n",
-			rsnd_mod_name(mod), rsnd_mod_id(mod));
-
 	return 0;
 }
 
-- 
1.9.1

Re: [PATCH v2] ASoC: rsnd: fix usrcnt decrementing bug

[Kuninori Morimoto]

Hi
> 
> Field usrcnt is unsigned so it cannot be lesser than zero.
> The patch fixes the check, moves it to the beginning of the function
> and changes return value to -EIO in case of usercnt error.
> 
> The problem has been detected using proposed semantic patch
> scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].
> 
> [1]: http://permalink.gmane.org/gmane.linux.kernel/2038576
> 
> Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
> ---

Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

Re: [PATCH v2] ASoC: rsnd: fix usrcnt decrementing bug

[Mark Brown]

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On Thu, Dec 24, 2015 at 08:02:39AM +0100, Andrzej Hajda wrote:
> Field usrcnt is unsigned so it cannot be lesser than zero.
> The patch fixes the check, moves it to the beginning of the function
> and changes return value to -EIO in case of usercnt error.

Please don't send new patches in reply to old ones, it makes it hard to
figure out what the current version of things is.

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Applied "ASoC: rsnd: fix usrcnt decrementing bug" to the asoc tree

[Mark Brown]

The patch

   ASoC: rsnd: fix usrcnt decrementing bug

has been applied to the asoc tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From e5d9cfc6f5fe56caa44cefbc7ef4531c480d901d Mon Sep 17 00:00:00 2001
From: Andrzej Hajda <a.hajda@samsung.com>
Date: Thu, 24 Dec 2015 08:02:39 +0100
Subject: [PATCH] ASoC: rsnd: fix usrcnt decrementing bug

Field usrcnt is unsigned so it cannot be lesser than zero.
The patch fixes the check, moves it to the beginning of the function
and changes return value to -EIO in case of usercnt error.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/sh/rcar/ssi.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c
index 7db05fdfb656..7ee89da4dd5f 100644
--- a/sound/soc/sh/rcar/ssi.c
+++ b/sound/soc/sh/rcar/ssi.c
@@ -403,29 +403,30 @@ static int rsnd_ssi_quit(struct rsnd_mod *mod,
 	struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod);
 	struct device *dev = rsnd_priv_to_dev(priv);
 
-	if (rsnd_ssi_is_parent(mod, io))
-		goto rsnd_ssi_quit_end;
+	if (!ssi->usrcnt) {
+		dev_err(dev, "%s[%d] usrcnt error\n",
+			rsnd_mod_name(mod), rsnd_mod_id(mod));
+		return -EIO;
+	}
 
-	if (ssi->err > 0)
-		dev_warn(dev, "%s[%d] under/over flow err = %d\n",
-			 rsnd_mod_name(mod), rsnd_mod_id(mod), ssi->err);
+	if (!rsnd_ssi_is_parent(mod, io)) {
+		if (ssi->err > 0)
+			dev_warn(dev, "%s[%d] under/over flow err = %d\n",
+				 rsnd_mod_name(mod), rsnd_mod_id(mod),
+				 ssi->err);
 
-	ssi->cr_own	= 0;
-	ssi->err	= 0;
+		ssi->cr_own	= 0;
+		ssi->err	= 0;
 
-	rsnd_ssi_irq_disable(mod);
+		rsnd_ssi_irq_disable(mod);
+	}
 
-rsnd_ssi_quit_end:
 	rsnd_ssi_master_clk_stop(ssi, io);
 
 	rsnd_mod_power_off(mod);
 
 	ssi->usrcnt--;
 
-	if (ssi->usrcnt < 0)
-		dev_err(dev, "%s[%d] usrcnt error\n",
-			rsnd_mod_name(mod), rsnd_mod_id(mod));
-
 	return 0;
 }
 
-- 
2.6.2