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Date: Mon, 10 Jun 2013 11:09:15 +0200
From: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20130610090915.GB3636@dhcp-200-207.str.redhat.com>
References: <1370742255-16400-1-git-send-email-famz@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] vmdk: refuse to open higher version than
	supported
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To: Fam Zheng <famz@redhat.com>
Cc: jcody@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com

Am 09.06.2013 um 03:44 hat Fam Zheng geschrieben:
> Refuse to open higher version for safety.
> 
> Although we try to be compatible with published VMDK spec, VMware has
> newer version from ESXi 5.1 exported OVF/OVA, which we have no knowledge
> what's changed in it. And it is very likely to have more new versions in
> the future, so it's not safe to open them blindly.
> 
> Signed-off-by: Fam Zheng <famz@redhat.com>

Yes, it's definitely a good idea to add a check.

> @@ -558,6 +558,10 @@ static int vmdk_open_vmdk4(BlockDriverState *bs,
>          header = footer.header;
>      }
>  
> +    if (le32_to_cpu(header.version) >= 3) {
> +        return -EINVAL;
> +    }
> +

Other block drivers return -ENOTSUP for this case, and also call
qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, ...) so that you get a
meaningful error message. Can you model the VMDK code after them?

Kevin