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Date: Fri, 23 Mar 2018 11:28:20 -0500
From: Seebs <seebs@seebs.net>
To: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
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Subject: Re: pseudo: host user contamination
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On Fri, 23 Mar 2018 17:10:35 +0100
Enrico Scholz <enrico.scholz@sigma-chemnitz.de> wrote:

> I think, 'mv' is the culprit.  It calls 'renameat2()' directly over
> 'syscall()':
> 
> | $ ltrace mv foo bar
> | ...
> | syscall(316, 0xffffff9c, 0x7fff1564a341,
> 0xffffff9c)                                            = 0
> 
> 
> Perhaps, 'pseudo' does not catch this?

Yeah.

And so far as I know, it's not actually *possible* to in the general
case. I really don't think it's safe to try to catch syscall().

I was afraid someone would do this. (It also breaks most Go programs,
for similar reasons; no libc calls.)

I have no idea why they're doing that; it seems distinctly unsafe.

-s