Subject: Re: mmap(), security and /dev/zero
To: None <tech-security@NetBSD.org, tech-kern@NetBSD.org>
From: Matt Thomas <email@example.com>
Date: 06/24/2004 10:00:14
On Jun 24, 2004, at 1:58 AM, Alan Barrett wrote:
> How does the following compromise sound?
> shlibs must be in files that have "r" permission.
> shlibs must be on file systems that honour "x" permission
> (that is, were not mounted with the noexec option).
Now that we have noexec permissions on pages (for some architectures),
make the mapping of vnode backed pages with PROT_EXEC only be allowed
on filesystems that were not mounted with noexec. Otherwise,
mmap/uvm_map/mprotect will return EPERM for the mapping operation.
Matt Thomas email: firstname.lastname@example.org
3am Software Foundry www: http://3am-software.com/bio/matt/
Cupertino, CA disclaimer: I avow all knowledge of this