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Message-ID: <d1259a80-ac2f-a164-685a-4d1763653021@acm.org>
Date:   Tue, 2 Nov 2021 20:32:33 -0700
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Subject: Re: [PATCH 1/2] scsi: scsi_ioctl: Validate command size
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To:     Tadeusz Struk <tadeusz.struk@linaro.org>,
        linux-scsi@vger.kernel.org
Cc:     Christoph Hellwig <hch@lst.de>,
        "James E . J . Bottomley" <jejb@linux.ibm.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
References: <20211103003719.1041490-1-tadeusz.struk@linaro.org>
From:   Bart Van Assche <bvanassche@acm.org>
In-Reply-To: <20211103003719.1041490-1-tadeusz.struk@linaro.org>
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On 11/2/21 17:37, Tadeusz Struk wrote:
> +	if (hdr->cmd_len < 6 || hdr->cmd_len > sizeof(req->__cmd))
> +		return -EMSGSIZE;

That doesn't look right to me since sg_io() allocates req->cmd if necessary:

	if (hdr->cmd_len > BLK_MAX_CDB) {
		req->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
		if (!req->cmd)
			goto out_put_request;
	}

Bart.