RE: [PATCH] exec: Force single empty string when argv is empty

[David Laight]

From: Kees Cook
> Sent: 01 February 2022 00:10
...
> While the initial code searches[6][7] turned up what appeared to be
> mostly corner case tests, trying to that just reject argv == NULL
> (or an immediately terminated pointer list) quickly started tripping[8]
> existing userspace programs.
> 
> The next best approach is forcing a single empty string into argv and
> adjusting argc to match. The number of programs depending on argc == 0
> seems a smaller set than those calling execve with a NULL argv.

Has anyone considered using the pathname for argv[0]?
So converting:
	execl(path, NULL);
into:
	execl(path, path, NULL);

I've not spotted any such suggestion.

	David

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