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Date:   Fri, 28 Aug 2020 10:46:56 -0400
From:   "Theodore Y. Ts'o" <tytso@mit.edu>
To:     Christian Schoenebeck <qemu_oss@crudebyte.com>
Cc:     "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Al Viro <viro@zeniv.linux.org.uk>,
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        Stefan Hajnoczi <stefanha@redhat.com>,
        Miklos Szeredi <mszeredi@redhat.com>,
        Vivek Goyal <vgoyal@redhat.com>,
        Giuseppe Scrivano <gscrivan@redhat.com>,
        Daniel J Walsh <dwalsh@redhat.com>,
        Chirantan Ekbote <chirantan@chromium.org>
Subject: Re: file forks vs. xattr (was: xattr names for unprivileged
 stacking?)
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 <11755866.l6z0jNX47O@silver>
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On Fri, Aug 28, 2020 at 11:11:15AM +0200, Christian Schoenebeck wrote:
> 
> Built-in path resolution would be nice, but it won't be a show stopper for 
> such common utils if not. For instance on Solaris there is:
> 
> runat <filename> <cmd> ...
> 
> which works something like fchdir(); execv(); you loose some flexibility, but 
> in practice still OK.

And we know from the Solaris experience that it was used *much* more
by malware authors (since most Unix security scanners didn't know
about forks) than any legitmate users.

Which is another way of saying, it's a bad idea --- unless you are a
malware author.

      	 	     		       - Ted