write permissions other than the run as user

[Todd C. Miller]

In message <536D05B1A86DD1119ACB00805FE66D0711702220 at alnexch1.aln.experian.com>
	so spake "Brown, Eugene" (Eugene.Brown):

> Is there a way or will there be a way to have an option to prevent the
> execution of a file that is write-able by groups or others. It would be nice
> that sudo verifies that if the file is writable other than by the run as
> user, then it won't execute the file in fear that it may have been modified
> by others. If a file is to be run as root but is write-able by other than
> root, it is possible for malicious code to have been added.

Any check for this would be subject to a winnable race condition
if the directory is writable by the invoking user since you have
to pass execve() a path, not a file descriptor.

 - todd