Messages in this thread | | | Subject | Re: [PATCH v2 0/3] initramfs: add support for xattrs in the initial ram disk | From | Roberto Sassu <> | Date | Fri, 10 May 2019 08:56:18 +0200 |
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On 5/9/2019 8:34 PM, Rob Landley wrote: > On 5/9/19 6:24 AM, Roberto Sassu wrote: >> This patch set aims at solving the following use case: appraise files from >> the initial ram disk. To do that, IMA checks the signature/hash from the >> security.ima xattr. Unfortunately, this use case cannot be implemented >> currently, as the CPIO format does not support xattrs. >> >> This proposal consists in marshaling pathnames and xattrs in a file called >> .xattr-list. They are unmarshaled by the CPIO parser after all files have >> been extracted. > > So it's in-band signalling that has a higher peak memory requirement.
This can be modified. Now I allocate the memory necessary for the path and all xattrs of a file (max: .xattr-list size - 10 bytes). I could process each xattr individually (max: 255 + 1 + 65536 bytes).
>> The difference with another proposal >> (https://lore.kernel.org/patchwork/cover/888071/) is that xattrs can be >> included in an image without changing the image format, as opposed to >> defining a new one. As seen from the discussion, if a new format has to be >> defined, it should fix the issues of the existing format, which requires >> more time. > > So you've explicitly chosen _not_ to address Y2038 while you're there.
Can you be more specific?
Thanks
Roberto
> Rob >
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