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Date:   Fri, 17 Nov 2023 19:19:45 +0100
From:   Alexander Gordeev <agordeev@linux.ibm.com>
To:     Kees Cook <keescook@chromium.org>
Cc:     Steffen Maier <maier@linux.ibm.com>,
        Benjamin Block <bblock@linux.ibm.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Christian Borntraeger <borntraeger@linux.ibm.com>,
        Sven Schnelle <svens@linux.ibm.com>,
        Azeem Shaikh <azeemshaikh38@gmail.com>,
        linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH] scsi: zfcp: Replace strlcpy() with strscpy()
Message-ID: <ZVeuwT1rhMT5UWGB@li-008a6a4c-3549-11b2-a85c-c5cc2836eea2.ibm.com>
References: <20231116191435.work.581-kees@kernel.org>
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On Thu, Nov 16, 2023 at 11:14:35AM -0800, Kees Cook wrote:

Hi Kees,

> diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c
> index 4f0d0e55f0d4..1a29f10767fc 100644
> --- a/drivers/s390/scsi/zfcp_fc.c
> +++ b/drivers/s390/scsi/zfcp_fc.c
> @@ -900,8 +900,15 @@ static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
>  	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
>  			   FC_SYMBOLIC_NAME_SIZE);
>  	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
> -	len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
> -		      FC_SYMBOLIC_NAME_SIZE);
> +	len = strscpy(rspn_req->name, fc_host_symbolic_name(shost),
> +		      sizeof(rspn_req->name));

Could you please explain why do you copy to rspn_req->name instead
of rspn_req->rspn.fr_name?

> +	/*
> +	 * It should be impossible for this to truncate, as
> +	 * sizeof(rspn_req->name) is equal to max size of
> +	 * fc_host_symbolic_name(shost), but check anyway.
> +	 */
> +	if (len < 0)
> +		len = sizeof(rspn_req->name) - 1;
>  	rspn_req->rspn.fr_name_len = len;
>  
>  	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));

Thanks!