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Date:   Thu, 30 Apr 2020 10:07:46 +0200
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Aleksa Sarai <cyphar@cyphar.com>
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Subject: Re: [PATCH v3 0/5] Add support for RESOLVE_MAYEXEC
Message-ID: <20200430080746.n26fja2444w6i2db@wittgenstein>
References: <20200428175129.634352-1-mic@digikod.net>
 <20200430015429.wuob7m5ofdewubui@yavin.dot.cyphar.com>
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On Thu, Apr 30, 2020 at 11:54:29AM +1000, Aleksa Sarai wrote:
> On 2020-04-28, Mickaël Salaün <mic@digikod.net> wrote:
> > The goal of this patch series is to enable to control script execution
> > with interpreters help.  A new RESOLVE_MAYEXEC flag, usable through
> > openat2(2), is added to enable userspace script interpreter to delegate
> > to the kernel (and thus the system security policy) the permission to
> > interpret/execute scripts or other files containing what can be seen as
> > commands.
> > 
> > This third patch series mainly differ from the previous one by relying
> > on the new openat2(2) system call to get rid of the undefined behavior
> > of the open(2) flags.  Thus, the previous O_MAYEXEC flag is now replaced
> > with the new RESOLVE_MAYEXEC flag and benefits from the openat2(2)
> > strict check of this kind of flags.
> 
> My only strong upfront objection is with this being a RESOLVE_ flag.
> 
> RESOLVE_ flags have a specific meaning (they generally apply to all
> components, and affect the rules of path resolution). RESOLVE_MAYEXEC
> does neither of these things and so seems out of place among the other
> RESOLVE_ flags.
> 
> I would argue this should be an O_ flag, but not supported for the

I agree.

Christian