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References: <20220126132729.GA7942@brightrain.aerifal.cx>
Subject: Re: [PATCH] fs/exec: require argv[0] presence in do_execveat_common()
Reply-To: 20220126132729.GA7942@brightrain.aerifal.cx
From:   hypervis0r <hypervis0r@phasetw0.com>
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Date:   Tue, 1 Feb 2022 12:54:08 -0800
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> I'm not really opposed  to attempting to change this with consensus
> (like, actually  proposing it on the Austin Group tracker), but a less
> invasive change would be  just enforcing it for the case where exec is
> a privilege boundary  (suid/sgid/caps). There's really no motivation
> for changing  longstanding standard behavior in a
> non-privilege-boundary  case.

I don't really see it as a matter of "maintaining standard behavior".

there are very little uses for this ABI feature to be present and only 
serves to make applications harder to port between Linux and other *nix 
systems. The pros (major vulnerabilities like CVE-2021-4034) outweigh 
the cons (minor userland ABI change that only affects shellcode on 
shell-storm.org) in this particular scenario, and I am all for this patch.