Messages in this thread | | | From | Linus Torvalds <> | Date | Sun, 21 Nov 2010 09:56:17 -0800 | Subject | Re: [PATCH v1.2 0/5] IMA: making i_readcount a first class inode citizen (reposting) |
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On Sun, Nov 21, 2010 at 5:18 AM, Mimi Zohar <zohar@linux.vnet.ibm.com> wrote: > > IMA (and the proposed EVM/IMA-appraisal patches) detects file change > based on i_version. When the file is closed, if the file has changed, > IMA marks the file as needing to be re-measured. Of course this requires > the filesystem to be mounted with iversion. Don't know if this helps.
If you only do this at close time, I see a _major_ security hole.
The attacker can just write to the file, and keep it open. Ta-daa, everybody who reads it sees the new contents, but your IMA logic is oblivious and thinks it doesn't need to be re-measured.
Linus
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