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From:   Florian Weimer <fweimer@redhat.com>
To:     =?utf-8?Q?Micka=C3=ABl_Sala=C3=BCn?= <mic@digikod.net>
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Subject: Re: [PATCH v2 1/5] fs: Add support for an O_MAYEXEC flag on sys_open()
References: <20190906152455.22757-1-mic@digikod.net>
        <20190906152455.22757-2-mic@digikod.net>
Date:   Fri, 06 Sep 2019 17:56:32 +0200
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Let's assume I want to add support for this to the glibc dynamic loader,
while still being able to run on older kernels.

Is it safe to try the open call first, with O_MAYEXEC, and if that fails
with EINVAL, try again without O_MAYEXEC?

Or do I risk disabling this security feature if I do that?

Do we need a different way for recognizing kernel support.  (Note that
we cannot probe paths in /proc for various reasons.)

Thanks,
Florian