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Date:   Thu, 4 Feb 2021 10:51:59 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Cc:     davem@davemloft.net, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org,
        syzbot+c2a7e5c5211605a90865@syzkaller.appspotmail.com
Subject: Re: [PATCH] net/qrtr: replaced useless kzalloc with kmalloc in
 qrtr_tun_write_iter()
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In-Reply-To: <20210204090230.1794169-1-snovitoll@gmail.com>
References: <20210203162846.56a90288@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
        <20210204090230.1794169-1-snovitoll@gmail.com>
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On Thu,  4 Feb 2021 15:02:30 +0600 Sabyrzhan Tasbolatov wrote:
> Replaced kzalloc() with kmalloc(), there is no need for zeroed-out
> memory for simple void *kbuf.

There is no need for zeroed-out memory because it's immediately
overwritten by copy_from_iter...

> >For potential, separate clean up - this is followed 
> >by copy_from_iter_full(len) kzalloc() can probably 
> >be replaced by kmalloc()?
> >  
> >>  	if (!kbuf)
> >>  		return -ENOMEM;  
> 
> Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
> ---
>  net/qrtr/tun.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/qrtr/tun.c b/net/qrtr/tun.c
> index b238c40a9984..9b607c7614de 100644
> --- a/net/qrtr/tun.c
> +++ b/net/qrtr/tun.c
> @@ -86,7 +86,7 @@ static ssize_t qrtr_tun_write_iter(struct kiocb *iocb, struct iov_iter *from)
>  	if (len > KMALLOC_MAX_SIZE)
>  		return -ENOMEM;
>  
> -	kbuf = kzalloc(len, GFP_KERNEL);
> +	kbuf = kmalloc(len, GFP_KERNEL);
>  	if (!kbuf)
>  		return -ENOMEM;
>