Bugtraq mailing list archives
Re: [patch] /proc race fixes for 2.2.1 (fwd)
From: e8903122 () student tuwien ac at (Richard Kail)
Date: Wed, 3 Feb 1999 13:50:52 +0100
Hello ! There seems to be anoter /proc race in the 2.2.1 linux kernel. I will explain this with an example: modprobe coda.o # will load coda.o as dynamically module # the kernel will create a /proc/fs/coda directory # on the fly. cd /proc/fs/coda # make shell chdir("/proc/fs/coda") rmmod coda.o # works ! (shouldn't) ls -l # generate a oops. after this, the coda.o module seems not to work at all. Maybe this is a systematic problem of more than one driver. I am not a kernel hacker, so I can't check all kernel modules for this kind of problem. Since a user can control the whole process I think has security implications. A user can trigger a "modprobe module" command using the kerneld (oh, its called kmod now...) mechanism. A user can chdir /proc/fs/coda. If the system has implemented the cron job as suggested in linux/Documentation/kmod.txt the user has just to wait with wd=/proc/fs/code to crash the system. Kind regards, Richard ------ "One day, computer power will eventually outstrip demand, and OS engineers will be free to use friendly languages like LISP again.. until then, I think we're stuck with C." -- Oliver Xymoro
Current thread:
- [patch] /proc race fixes for 2.2.1 (fwd) Andrea Arcangeli (Feb 02)
- Re: [patch] /proc race fixes for 2.2.1 (fwd) Richard Kail (Feb 03)
- [patch] Re: [patch] /proc race fixes for 2.2.1 (fwd) Andrea Arcangeli (Feb 03)
- Re: [patch] /proc race fixes for 2.2.1 (fwd) Andrea Arcangeli (Feb 04)
- Re: [patch] /proc race fixes for 2.2.1 (fwd) Richard Kail (Feb 03)