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Date:   Wed, 26 Jan 2022 15:57:35 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Heikki Kallasjoki <heikki.kallasjoki@iki.fi>
Cc:     Ariadne Conill <ariadne@dereferenced.org>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Eric Biederman <ebiederm@xmission.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH] fs/exec: require argv[0] presence in do_execveat_common()
Message-ID: <202201261545.D955A71E@keescook>
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On Wed, Jan 26, 2022 at 12:33:39PM +0000, Heikki Kallasjoki wrote:
> On Wed, Jan 26, 2022 at 05:18:58AM -0600, Ariadne Conill wrote:
> > On Tue, 25 Jan 2022, Kees Cook wrote:
> > > Lots of stuff likes to do:
> > > execve(path, NULL, NULL);
> > 
> > I looked at these, and these seem to basically be lazily-written test cases
> > which should be fixed.  I didn't see any example of real-world applications
> > doing this.  As noted in some of the test cases, there are comments like
> > "Solaris doesn't support this," etc.
> 
> See also the (small) handful of instances of `execlp(cmd, NULL);` out
> there, which I imagine would start to fail:
> https://codesearch.debian.net/search?q=execlp%3F%5Cs*%5C%28%5B%5E%2C%5D%2B%2C%5Cs*NULL&literal=0
> 
> Two of the hits (ispell, nauty) would seem to be non-test use cases.

Ah yeah, I've added this to the Issue tracker:
https://github.com/KSPP/linux/issues/176

-- 
Kees Cook