Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-10 Thread halfdog
PaX Team wrote: > On 7 Oct 2012 at 9:43, Ard Biesheuvel wrote: > >> 2012/10/6 PaX Team : >>> sadly, this is not true at all, for multiple reasons: >>> >> .. snip ... >>> >>> cheers, >>> PaX Team >>> >> >> So can I summarize your position as that there is no merit at all in >> the ability to inhi

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-07 Thread PaX Team
On 7 Oct 2012 at 9:43, Ard Biesheuvel wrote: > 2012/10/6 PaX Team : > > sadly, this is not true at all, for multiple reasons: > > > .. snip ... > > > > cheers, > > PaX Team > > > > So can I summarize your position as that there is no merit at all in > the ability to inhibit future permissions o

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-07 Thread Ard Biesheuvel
2012/10/6 PaX Team : > sadly, this is not true at all, for multiple reasons: > .. snip ... > > cheers, > PaX Team > So can I summarize your position as that there is no merit at all in the ability to inhibit future permissions of existing mappings? -- Ard. -- To unsubscribe from this list: sen

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-06 Thread PaX Team
On 4 Oct 2012 at 15:56, Ard Biesheuvel wrote: > 2012/10/4 PaX Team : > The main difference here is that it is much easier to doctor a set of > stack frames that issues a mprotect(+PROT_EXEC) on the whole address > space than it is to re-issue the exact same mmap() call (with > MAP_FIXED this time,

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-04 Thread Ard Biesheuvel
2012/10/4 PaX Team : Thanks for taking a look at this matter. >> >> This is mainly intended for the dynamic linker, >> >> which sets up the address space on behalf of >> >> dynamic binaries. By using this flag, it can >> >> prevent exploited code from remapping read-only >> >> executable code or

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-04 Thread PaX Team
On 3 Oct 2012 at 15:19, Kees Cook wrote: > On Wed, Oct 3, 2012 at 2:18 PM, Andrew Morton > wrote: > > It sounds as though the PaX developers could provide useful review > > input on this proposal. Do they know about it? If so, what is their > > position? > > I'd rather not speak for them, but

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-04 Thread Ard Biesheuvel
2012/10/4 Mikael Pettersson : > - If .text is mapped non-writable and final, how would a debugger > (or any ptrace-using monitor-like application) plant a large > number of breakpoints in a target process? Breakpoint registers > aren't enough because (a) they're few in number, and (b) not >

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-04 Thread Ard Biesheuvel
2012/10/4 Kees Cook : > On Wed, Oct 3, 2012 at 2:18 PM, Andrew Morton > wrote: >> Again: has this proposal been reviewed by the glibc maintainers? If >> so, what was their position on it? > > Ard have you talked with them? I would expect it would be welcomed. > Roland, do you know who would be t

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-04 Thread Mikael Pettersson
Ard Biesheuvel writes: > This patch adds support for the PROT_FINAL flag to > the mmap() and mprotect() syscalls. > > The PROT_FINAL flag indicates that the requested set > of protection bits should be final, i.e., it shall > not be allowed for a subsequent mprotect call to > set protection

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-03 Thread Roland McGrath
> > Again: has this proposal been reviewed by the glibc maintainers? If > > so, what was their position on it? > > Ard have you talked with them? I would expect it would be welcomed. > Roland, do you know who would be the right person to ask about this > for glibc? (patch: https://lkml.org/lkml/2

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-03 Thread Kees Cook
On Wed, Oct 3, 2012 at 2:18 PM, Andrew Morton wrote: > On Wed, 03 Oct 2012 16:43:53 +0200 > Ard Biesheuvel wrote: > >> This patch adds support for the PROT_FINAL flag to >> the mmap() and mprotect() syscalls. >> >> The PROT_FINAL flag indicates that the requested set >> of protection bits should

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-03 Thread Andrew Morton
On Wed, 03 Oct 2012 16:43:53 +0200 Ard Biesheuvel wrote: > This patch adds support for the PROT_FINAL flag to > the mmap() and mprotect() syscalls. > > The PROT_FINAL flag indicates that the requested set > of protection bits should be final, i.e., it shall > not be allowed for a subsequent mpro

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-03 Thread Hugh Dickins
On Wed, 3 Oct 2012, Ard Biesheuvel wrote: > This patch adds support for the PROT_FINAL flag to > the mmap() and mprotect() syscalls. > > The PROT_FINAL flag indicates that the requested set > of protection bits should be final, i.e., it shall > not be allowed for a subsequent mprotect call to > s

Re: Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-03 Thread Kees Cook
On Wed, Oct 3, 2012 at 7:43 AM, Ard Biesheuvel wrote: > This patch adds support for the PROT_FINAL flag to > the mmap() and mprotect() syscalls. > > The PROT_FINAL flag indicates that the requested set > of protection bits should be final, i.e., it shall > not be allowed for a subsequent mprotect

Updated: [PATCH] hardening: add PROT_FINAL prot flag to mmap/mprotect

2012-10-03 Thread Ard Biesheuvel
This patch adds support for the PROT_FINAL flag to the mmap() and mprotect() syscalls. The PROT_FINAL flag indicates that the requested set of protection bits should be final, i.e., it shall not be allowed for a subsequent mprotect call to set protection bits that were not set already. This is ma