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From:   Florian Weimer <fweimer@redhat.com>
To:     Steve Grubb <sgrubb@redhat.com>
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Subject: Re: [PATCH v2 0/5] Add support for O_MAYEXEC
References: <20190906152455.22757-1-mic@digikod.net> <2989749.1YmIBkDdQn@x2>
Date:   Fri, 06 Sep 2019 20:57:00 +0200
In-Reply-To: <2989749.1YmIBkDdQn@x2> (Steve Grubb's message of "Fri, 06 Sep
        2019 14:50:02 -0400")
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* Steve Grubb:

> Now with LD_AUDIT
> $ LD_AUDIT=/home/sgrubb/test/openflags/strip-flags.so.0 strace ./test 2>&1 | grep passwd
> openat(3, "passwd", O_RDONLY)           = 4
>
> No O_CLOEXEC flag.

I think you need to explain in detail why you consider this a problem.

With LD_PRELOAD and LD_AUDIT, you can already do anything, including
scanning other loaded objects for a system call instruction and jumping
to that (in case a security module in the kernel performs a PC check to
confer additional privileges).

Thanks,
Florian