Date: Mon, 7 Dec 2015 09:48:47 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Saurabh Sengar <saurabh.truth@gmail.com>
Cc: w.d.hubbs@gmail.com, chris@the-brannons.com, kirk@reisers.ca,
        samuel.thibault@ens-lyon.org, gregkh@linuxfoundation.org,
        speakup@linux-speakup.org, devel@driverdev.osuosl.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Staging: speakup: kobjects: Return the error type to
 caller
Message-ID: <20151207064847.GA18797@mwanda>
References: <1449240153-3927-1-git-send-email-saurabh.truth@gmail.com>
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On Fri, Dec 04, 2015 at 08:12:33PM +0530, Saurabh Sengar wrote:
> Inorder to notify the user that value is not successfuly set in sys
> entry, error should be returned from store function instead of count
> 
> Signed-off-by: Saurabh Sengar <saurabh.truth@gmail.com>
> ---
>  drivers/staging/speakup/kobjects.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/speakup/kobjects.c b/drivers/staging/speakup/kobjects.c
> index fdfeb42..b3a83fb 100644
> --- a/drivers/staging/speakup/kobjects.c
> +++ b/drivers/staging/speakup/kobjects.c
> @@ -640,7 +640,8 @@ ssize_t spk_var_store(struct kobject *kobj, struct kobj_attribute *attr,
>  			len = E_INC;
>  		else
>  			len = E_SET;
> -		if (kstrtol(cp, 10, &value) == 0)
> +		ret = kstrtol(cp, 10, &value);
> +		if (!ret)
>  			ret = spk_set_num_var(value, param, len);

Both kstrtol() and spk_set_num_var() return -ERANGE.  The next lines
expect that if we got -ERANGE, then it came from spk_set_num_var() so
they print a wrong message.

>  		else
>  			pr_warn("overflow or parsing error has occurred");
> @@ -688,6 +689,8 @@ ssize_t spk_var_store(struct kobject *kobj, struct kobj_attribute *attr,
>  
>  	if (ret == -ERESTART)
>  		pr_info("%s reset to default value\n", param->name);

Is this really true?

This function is so weird and broken.  Please look at it some more and
fix it harder with a mallet.

regards,
dan carpenter

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