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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