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Aucbvax.5396 net.2bsd-bugs utzoo!decvax!ucbvax!dist2 Sun Dec 6 02:58:31 1981 FIXED: bug in src/more/more.c There is a bug in "more" which raises its ugly head when the input to more is a pipe, and a shell escape is performed. The piped input becomes piped to the shell escape causing all sorts of mysterious results, at least when the shell escape reads standard input. This problem commonly appears reading netnews. The fix is simple -- if stdin is not from a tty, it must be closed before exec'ing the shell escape.

I know of some sites which take advantage of this bug to allow free logins to use more without worrying about the security problems inherent with being able to fork subshells. Nevertheless, it is a bug and exists in 4.1BSD as well. The suggested fix works as well as anything:

diff src/more/more.c.old src/more/more.c 1077a1078,1081 > if (no_intty) { > close(0); > dup(2); > }

This change is necessary on tapes written before 12/5/81.

Carl

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