Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Sender: Vineet Gupta <vineetg76@gmail.com>
Subject: Re: [PATCH] arc: kernel: Return -EFAULT if copy_to_user() fails
To:     Wang Qing <wangqing@vivo.com>, Jens Axboe <axboe@kernel.dk>,
        Thomas Gleixner <tglx@linutronix.de>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        linux-snps-arc@lists.infradead.org, linux-kernel@vger.kernel.org
Newsgroups: gmane.linux.kernel,gmane.linux.kernel.arc
References: <1614600349-15662-1-git-send-email-wangqing@vivo.com>
From:   Vineet Gupta <vgupta@synopsys.com>
Message-ID: <bed81c02-97e0-9905-0dd3-6064a54691ff@synopsys.com>
Date:   Tue, 2 Mar 2021 11:01:11 -0800
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.7.1
MIME-Version: 1.0
In-Reply-To: <1614600349-15662-1-git-send-email-wangqing@vivo.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 3/1/21 4:05 AM, Wang Qing wrote:
> The copy_to_user() function returns the number of bytes remaining to be
> copied, but we want to return -EFAULT if the copy doesn't complete.
> 
> Signed-off-by: Wang Qing <wangqing@vivo.com>

Acked-by: Vineet Gupta <vgupta@synopsys.com>

Do you want me to pick this up via ARC tree ?

Thx,
-Vineet

> ---
>   arch/arc/kernel/signal.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c
> index a78d8f7..fdbe06c
> --- a/arch/arc/kernel/signal.c
> +++ b/arch/arc/kernel/signal.c
> @@ -96,7 +96,7 @@ stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs,
>   			     sizeof(sf->uc.uc_mcontext.regs.scratch));
>   	err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t));
>   
> -	return err;
> +	return err ? -EFAULT : 0;
>   }
>   
>   static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
> @@ -110,7 +110,7 @@ static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
>   				&(sf->uc.uc_mcontext.regs.scratch),
>   				sizeof(sf->uc.uc_mcontext.regs.scratch));
>   	if (err)
> -		return err;
> +		return -EFAULT;
>   
>   	set_current_blocked(&set);
>   	regs->bta	= uregs.scratch.bta;
>