Bugtraq mailing list archives
Re: When scrubbing secrets in memory doesn't work
From: Peter Watkins <peterw () usa net>
Date: Mon, 18 Nov 2002 13:19:38 -0500
On Mon, Nov 18, 2002 at 04:36:57PM +0000, Richard Moore wrote:
Nicholas Weaver wrote:On Thu, Nov 14, 2002 at 02:44:58AM -0800, Michael Wojcik composed: The bigger concern is when the memory is paged to disk, and that record may have a much MUCH longer time window. But scrubbing has no real effect on this
It's worth noting that on systems such as linux and solaris, it is easy to avoid the paging problem by locking the process into memory. This is accomplished using the system calls mlock(2) and mlockall(2).
Nice idea, except mlock() and mlockall() are only permissable when the effective userid is that of the superuser. (We touched on this a while back when discussing GnuPG; IIRC, in general Unix systems don't allow regular user processes to lock memory pages, while Windows' win32 API does allow such behavior.[0]) -Peter [0] The good news is that win32 has a setting for allowing user processes to lock pages that is distinct from the effective userid/gid; the bad news is that it's set per-user instead of per app; to allow users to run apps that insist on physical pages for memory allocation, it looks like you have to grant them the ability to effectively DoS the machine by grabbing all its physical memory. Oops. http://www.microsoft.com/msj/defaultframe.asp?page=/msj/1099/win32/win321099.htm&nav=/msj/1099/newnav.htm -- Peter Watkins - peterw () tux org - peterw () usa net - http://www.tux.org/~peterw/ Private personal mail: use PGP key F4F397A8; more sensitive data? Use 2D123692
Current thread:
- Re: When scrubbing secrets in memory doesn't work, (continued)
- Re: When scrubbing secrets in memory doesn't work Gianni Tedesco (Nov 07)
- Re: When scrubbing secrets in memory doesn't work Valdis . Kletnieks (Nov 08)
- Re: When scrubbing secrets in memory doesn't work Michael Zimmermann (Nov 09)
- Re: When scrubbing secrets in memory doesn't work Jan Echternach (Nov 14)
- When scrubbing secrets in memory doesn't work Michael Howard (Nov 09)
- RE: When scrubbing secrets in memory doesn't work Michael Wojcik (Nov 12)
- RE: When scrubbing secrets in memory doesn't work Michael Wojcik (Nov 17)
- Re: When scrubbing secrets in memory doesn't work Nicholas Weaver (Nov 18)
- Re: When scrubbing secrets in memory doesn't work Richard Moore (Nov 20)
- Re: When scrubbing secrets in memory doesn't work Florian Weimer (Nov 18)
- Re: When scrubbing secrets in memory doesn't work Peter Watkins (Nov 19)
- Re: When scrubbing secrets in memory doesn't work Nicholas Weaver (Nov 18)
- Re: When scrubbing secrets in memory doesn't work Gianni Tedesco (Nov 07)