[PATCH v3] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table

[PATCH v3] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table

[Heiner Kallweit]

If registering the platform device fails, the lookup table is
removed in the error path. On module removal we would try to
remove the lookup table again. Fix this by setting priv->lookup
only if registering the platform device was successful.
In addition free the memory allocated for the lookup table in
the error path.

Fixes: d308dfbf62ef ("i2c: mux/i801: Switch to use descriptor passing")
Cc: stable@vger.kernel.org
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- cc stable
- free memory allocated for the lookup table
v3:
- cc'ed Linus
---
 drivers/i2c/busses/i2c-i801.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 291c609d1..9c624f31c 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -1428,7 +1428,6 @@ static void i801_add_mux(struct i801_priv *priv)
 		lookup->table[i] = GPIO_LOOKUP(mux_config->gpio_chip,
 					       mux_config->gpios[i], "mux", 0);
 	gpiod_add_lookup_table(lookup);
-	priv->lookup = lookup;
 
 	/*
 	 * Register the mux device, we use PLATFORM_DEVID_NONE here
@@ -1442,7 +1441,10 @@ static void i801_add_mux(struct i801_priv *priv)
 				sizeof(struct i2c_mux_gpio_platform_data));
 	if (IS_ERR(priv->mux_pdev)) {
 		gpiod_remove_lookup_table(lookup);
+		devm_kfree(dev, lookup);
 		dev_err(dev, "Failed to register i2c-mux-gpio device\n");
+	} else {
+		priv->lookup = lookup;
 	}
 }
 
-- 
2.44.0

Re: [PATCH v3] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table

[Andi Shyti]

Hi Heiner,

On Mon, Mar 04, 2024 at 09:31:06PM +0100, Heiner Kallweit wrote:
> If registering the platform device fails, the lookup table is
> removed in the error path. On module removal we would try to
> remove the lookup table again. Fix this by setting priv->lookup
> only if registering the platform device was successful.
> In addition free the memory allocated for the lookup table in
> the error path.
> 
> Fixes: d308dfbf62ef ("i2c: mux/i801: Switch to use descriptor passing")
> Cc: stable@vger.kernel.org
> Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
> v2:
> - cc stable
> - free memory allocated for the lookup table
> v3:
> - cc'ed Linus

this patch is a resend...

> ---
>  drivers/i2c/busses/i2c-i801.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
> index 291c609d1..9c624f31c 100644
> --- a/drivers/i2c/busses/i2c-i801.c
> +++ b/drivers/i2c/busses/i2c-i801.c
> @@ -1428,7 +1428,6 @@ static void i801_add_mux(struct i801_priv *priv)
>  		lookup->table[i] = GPIO_LOOKUP(mux_config->gpio_chip,
>  					       mux_config->gpios[i], "mux", 0);
>  	gpiod_add_lookup_table(lookup);
> -	priv->lookup = lookup;

if I miss something obvious in my reviews, please let me know...
I spend most of my time reviewing patches and it happens quite
often :-)

Andi

>  	/*
>  	 * Register the mux device, we use PLATFORM_DEVID_NONE here
> @@ -1442,7 +1441,10 @@ static void i801_add_mux(struct i801_priv *priv)
>  				sizeof(struct i2c_mux_gpio_platform_data));
>  	if (IS_ERR(priv->mux_pdev)) {
>  		gpiod_remove_lookup_table(lookup);
> +		devm_kfree(dev, lookup);
>  		dev_err(dev, "Failed to register i2c-mux-gpio device\n");
> +	} else {
> +		priv->lookup = lookup;
>  	}
>  }
>  
> -- 
> 2.44.0
> 

Re: [PATCH v3] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table

[Heiner Kallweit]

On 05.03.2024 00:04, Andi Shyti wrote:
> Hi Heiner,
> 
> On Mon, Mar 04, 2024 at 09:31:06PM +0100, Heiner Kallweit wrote:
>> If registering the platform device fails, the lookup table is
>> removed in the error path. On module removal we would try to
>> remove the lookup table again. Fix this by setting priv->lookup
>> only if registering the platform device was successful.
>> In addition free the memory allocated for the lookup table in
>> the error path.
>>
>> Fixes: d308dfbf62ef ("i2c: mux/i801: Switch to use descriptor passing")
>> Cc: stable@vger.kernel.org
>> Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>> ---
>> v2:
>> - cc stable
>> - free memory allocated for the lookup table
>> v3:
>> - cc'ed Linus
> 
> this patch is a resend...
> 
Right, it's effectively a resend.

>> ---
>>  drivers/i2c/busses/i2c-i801.c | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
>> index 291c609d1..9c624f31c 100644
>> --- a/drivers/i2c/busses/i2c-i801.c
>> +++ b/drivers/i2c/busses/i2c-i801.c
>> @@ -1428,7 +1428,6 @@ static void i801_add_mux(struct i801_priv *priv)
>>  		lookup->table[i] = GPIO_LOOKUP(mux_config->gpio_chip,
>>  					       mux_config->gpios[i], "mux", 0);
>>  	gpiod_add_lookup_table(lookup);
>> -	priv->lookup = lookup;
> 
> if I miss something obvious in my reviews, please let me know...
> I spend most of my time reviewing patches and it happens quite
> often :-)
> 
> Andi
> 
>>  	/*
>>  	 * Register the mux device, we use PLATFORM_DEVID_NONE here
>> @@ -1442,7 +1441,10 @@ static void i801_add_mux(struct i801_priv *priv)
>>  				sizeof(struct i2c_mux_gpio_platform_data));
>>  	if (IS_ERR(priv->mux_pdev)) {
>>  		gpiod_remove_lookup_table(lookup);
>> +		devm_kfree(dev, lookup);
>>  		dev_err(dev, "Failed to register i2c-mux-gpio device\n");
>> +	} else {
>> +		priv->lookup = lookup;
>>  	}
>>  }
>>  
>> -- 
>> 2.44.0
>>

Re: [PATCH v3] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table

[Linus Walleij]

On Mon, Mar 4, 2024 at 9:31 PM Heiner Kallweit <hkallweit1@gmail.com> wrote:

> If registering the platform device fails, the lookup table is
> removed in the error path. On module removal we would try to
> remove the lookup table again. Fix this by setting priv->lookup
> only if registering the platform device was successful.
> In addition free the memory allocated for the lookup table in
> the error path.
>
> Fixes: d308dfbf62ef ("i2c: mux/i801: Switch to use descriptor passing")
> Cc: stable@vger.kernel.org
> Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> ---
> v2:
> - cc stable
> - free memory allocated for the lookup table
> v3:
> - cc'ed Linus

My bug I guess, mea culpa.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

Re: [SPAM] Re: [PATCH v3] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table

[Andi Shyti]

Hi Linus,

> > If registering the platform device fails, the lookup table is
> > removed in the error path. On module removal we would try to
> > remove the lookup table again. Fix this by setting priv->lookup
> > only if registering the platform device was successful.
> > In addition free the memory allocated for the lookup table in
> > the error path.
> >
> > Fixes: d308dfbf62ef ("i2c: mux/i801: Switch to use descriptor passing")
> > Cc: stable@vger.kernel.org
> > Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
> > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> > ---
> > v2:
> > - cc stable
> > - free memory allocated for the lookup table
> > v3:
> > - cc'ed Linus
> 
> My bug I guess, mea culpa.
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Thanks for your review! I have pushed this patch only in my
testing branch so that i can still add your r-b.

Andi

Re: [PATCH v3] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table

[Andi Shyti]

Hi

On Mon, 04 Mar 2024 21:31:06 +0100, Heiner Kallweit wrote:
> If registering the platform device fails, the lookup table is
> removed in the error path. On module removal we would try to
> remove the lookup table again. Fix this by setting priv->lookup
> only if registering the platform device was successful.
> In addition free the memory allocated for the lookup table in
> the error path.
> 
> [...]

Applied to i2c/i2c-host-fixes on

git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux.git

Thank you,
Andi

Patches applied
===============
[1/1] i2c: i801: Avoid potential double call to gpiod_remove_lookup_table
      commit: 7c16cfd69d519ba14c9e9d474facd22d075ad14d