[PATCH] lib: parameter: Free previous string value in param_string_set

[PATCH] lib: parameter: Free previous string value in param_string_set

[Robin van der Gracht]

When the parameter has no set function the previous (saved_value) is not
freed up on completion.

Signed-off-by: Robin van der Gracht <robin@protonic.nl>
---
 lib/parameter.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/parameter.c b/lib/parameter.c
index adc3c7cdea..fe7e7b1ba4 100644
--- a/lib/parameter.c
+++ b/lib/parameter.c
@@ -262,8 +262,10 @@ static int param_string_set(struct device_d *dev, struct param_d *p, const char
 	value_new = strim(value_new);
 	*ps->value = value_new;
 
-	if (!ps->set)
+	if (!ps->set) {
+		free(value_save);
 		return 0;
+	}
 
 	ret = ps->set(p, p->driver_priv);
 	if (ret) {
-- 
2.34.1

Re: [PATCH] lib: parameter: Free previous string value in param_string_set

[Sascha Hauer]

On Thu, Jun 16, 2022 at 02:50:40PM +0200, Robin van der Gracht wrote:
> When the parameter has no set function the previous (saved_value) is not
> freed up on completion.
> 
> Signed-off-by: Robin van der Gracht <robin@protonic.nl>
> ---
>  lib/parameter.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/parameter.c b/lib/parameter.c
> index adc3c7cdea..fe7e7b1ba4 100644
> --- a/lib/parameter.c
> +++ b/lib/parameter.c
> @@ -262,8 +262,10 @@ static int param_string_set(struct device_d *dev, struct param_d *p, const char
>  	value_new = strim(value_new);
>  	*ps->value = value_new;
>  
> -	if (!ps->set)
> +	if (!ps->set) {
> +		free(value_save);
>  		return 0;
> +	}

Fixing this bug reveals another one. We do a:

	value_new = xstrdup(val);
	value_new = strim(value_new);

When 'val' has whitespaces at the beginning we no longer free the
pointer originally returned from xstrdup, but the pointer with
whitespaces stripped. I'll queue a fix for this before this patch.

Sascha

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Re: [PATCH] lib: parameter: Free previous string value in param_string_set

[Robin van der Gracht]

On 2022-06-16 15:50, Sascha Hauer wrote:
> On Thu, Jun 16, 2022 at 02:50:40PM +0200, Robin van der Gracht wrote:
>> When the parameter has no set function the previous (saved_value) is not
>> freed up on completion.
>> 
>> Signed-off-by: Robin van der Gracht <robin@protonic.nl>
>> ---
>>  lib/parameter.c | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>> 
>> diff --git a/lib/parameter.c b/lib/parameter.c
>> index adc3c7cdea..fe7e7b1ba4 100644
>> --- a/lib/parameter.c
>> +++ b/lib/parameter.c
>> @@ -262,8 +262,10 @@ static int param_string_set(struct device_d *dev, 
>> struct param_d *p, const char
>>  	value_new = strim(value_new);
>>  	*ps->value = value_new;
>> 
>> -	if (!ps->set)
>> +	if (!ps->set) {
>> +		free(value_save);
>>  		return 0;
>> +	}
> 
> Fixing this bug reveals another one. We do a:
> 
> 	value_new = xstrdup(val);
> 	value_new = strim(value_new);
> 
> When 'val' has whitespaces at the beginning we no longer free the
> pointer originally returned from xstrdup, but the pointer with
> whitespaces stripped. I'll queue a fix for this before this patch.

Good catch.

ACK

- Robin