Kmem security (was: Re: How do you make your UNIX crash ???)

[Chris G. Demetriou]

In article <638 at minya.UUCP> jc at minya.UUCP (John Chambers) writes:

   In article <1991Mar24.203327.18426 at ttank.ttank.com>, tts at ttank.ttank.com (Karl Bunch) writes:

   > Safer would be:
   > strings /dev/kmem | tr ' ' '^J' | sort -u | more
   > and do a /rootpassword

   OK; that didn't crash the system; I just got a few random-looking strings,
   followed by::
	   /rootpassword: Command not found.
   What was it supposed to do?  Maybe I'm not a real Unix hacker, after
   all; I haven't even heard of a "rootpassword" command.  Am I missing
   something good?  I also looked around on some of the BSD and Ultrix
   systems at work, and there was nothing called "rootpassword" anywhere
   in any of their filesystems.

Umm, it would seem that the original author assumed that strings |...|more
would get more than a page of strings piped into more....

if this was the case, /rootpassword (where rootpassword is the root pw)
would search for the password in the text, and find the first occurrence
of it in the rest of the text.

this has several problems:

first, if the text is longer than a page, you never get to the "--MORE--"
line (or whatever more says to you at the end of a page).

second, if the root pw is on the first page, searching for it won't find
it unless it occurs again later; /blah searches for "blah" in the portion
of the file not yet displayed.

Chris Demetriou
cgd at ocf.berkeley.edu