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Sender: Corey Minyard <tcminyard@gmail.com>
Date:   Fri, 23 Jul 2021 07:24:40 -0500
From:   Corey Minyard <minyard@acm.org>
To:     Dan Carpenter <dan.carpenter@oracle.com>
Cc:     Quan Nguyen <quan@os.amperecomputing.com>,
        openipmi-developer@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] ipmi: ssif_bmc: Return -EFAULT if copy_from_user() fails
Message-ID: <20210723122440.GM3406@minyard.net>
Reply-To: minyard@acm.org
References: <20210723084459.GA21470@kili>
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On Fri, Jul 23, 2021 at 11:44:59AM +0300, Dan Carpenter wrote:
> The copy_from_user() function returns the number of bytes remaining to
> be copied but we should return -EFAULT here.

Yep, this is in my queue.

Thanks,

-corey

> 
> Fixes: 007888f365c9 ("ipmi: ssif_bmc: Add SSIF BMC driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
>  drivers/char/ipmi/ssif_bmc.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/char/ipmi/ssif_bmc.c b/drivers/char/ipmi/ssif_bmc.c
> index b15c05622e72..ce8cd8364a3f 100644
> --- a/drivers/char/ipmi/ssif_bmc.c
> +++ b/drivers/char/ipmi/ssif_bmc.c
> @@ -85,9 +85,8 @@ static ssize_t ssif_bmc_write(struct file *file, const char __user *buf, size_t
>  	if (count > sizeof(struct ssif_msg))
>  		return -EINVAL;
>  
> -	ret = copy_from_user(&msg, buf, count);
> -	if (ret)
> -		return ret;
> +	if (copy_from_user(&msg, buf, count))
> +		return -EFAULT;
>  
>  	if (!msg.len || count < ssif_msg_len(&msg))
>  		return -EINVAL;
> -- 
> 2.20.1
>