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Subject: Re: [RFC PATCH v1 0/5] Add support for O_MAYEXEC
From: Mimi Zohar <zohar@linux.ibm.com>
To: Florian Weimer <fweimer@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>,
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Date: Thu, 13 Dec 2018 07:16:52 -0500
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[Cc'ing linux-integrity]

On Thu, 2018-12-13 at 12:26 +0100, Florian Weimer wrote:
> * Mimi Zohar:
> 
> > The indication needs to be set during file open, before the open
> > returns to the caller.  This is the point where ima_file_check()
> > verifies the file's signature.  On failure, access to the file is
> > denied.
> 
> Does this verification happen for open with O_PATH?

Interesting!  According to the manpage, userspace cannot read/write to
the file.  It looks like do_o_path() intentionally skips do_last(),
with the call to ima_file_check().  If the file data isn't being
accessed, does the file's integrity need to be verified?

Mimi