Bugtraq mailing list archives
Re: WARNING: Linux Intel Pentium Bug
From: newsham () LAVA NET (Tim Newsham)
Date: Fri, 7 Nov 1997 12:49:41 -1000
Ran it on my P166, kaboom, ran it on my new P166MMX, kaboom. I guess that would be a yes. This is kind of scary, is there any possibility of a kernel patch that can take care of this?
There are checks you could do from the kernel but they would not be able to reliably detect an arbitrary program which would cause this instruction to run. In other words, if I saw your patch, i could easily write a program that gets around it. quick ideas that have been discussed with others: - check for the instruction problem: i can synthesize the instruction at run time - check to see if the code synthesizes and runs the instruction problem: you cant do this statically (its undecideable) and to do it dynamically you'd have to interpret every instruction you executed (too costly) - dont allow code to run out of stack problem: i can synthesize it elsewhere - dont allow code to run out of anything but the read-only text segment. problem: i can change the protection on the text segment - force text segment to always be read-only forcing code to run out of text could cause some existing programs to break.
-seifried
Tim N.
Current thread:
- Re: Intel Pentium Bug, (continued)
- Re: Intel Pentium Bug Colin Jenkins (Nov 07)
- Re: Intel Pentium Bug George Imburgia (Nov 07)
- Re: Intel Pentium Bug Travis Hassloch (Nov 11)
- Re: WARNING: Linux Intel Pentium Bug Alan Cox (Nov 08)
- Re: WARNING: Linux Intel Pentium Bug Roger Espel Llima (Nov 09)
- solaris (fwd) Rob Hagopian (Nov 09)
- Re: solaris (fwd) Corey Lindsly (Nov 09)
- Re: solaris (fwd) James Lockwood (Nov 09)
- Re: solaris (fwd) Dalvenjah FoxFire (Nov 09)
- Re: WARNING: Linux Intel Pentium Bug Kurt Seifried (Nov 07)
- Re: WARNING: Linux Intel Pentium Bug Tim Newsham (Nov 07)
- Re: WARNING: Linux Intel Pentium Bug Alan Cox (Nov 08)
- Outdated DNS and syslog Aaron Schultz (Nov 07)