[Xen-bugs] [Bug 1189] New: Xen's paravirt won't boot a PaX patched kernel (2.6.24.3)

[bugzilla-daemon@xxxxxxxxxxxxxxxxxxx]

http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1189

           Summary: Xen's paravirt won't boot a PaX patched kernel
                    (2.6.24.3)
           Product: Xen
           Version: unstable
          Platform: x86
        OS/Version: Linux-2.6
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Hypervisor
        AssignedTo: xen-bugs@xxxxxxxxxxxxxxxxxxx
        ReportedBy: a.grassi@xxxxxxxxxxxxxx


I'm running Xen Hypervisor 3.2.0-2, backported on Debian etch from sid, with a
Debian-patched Linux 2.6.18 as dom0

While a vanilla 2.6.24 (which includes domU support) boots normally, a kernel
patched with PaX (www.grsecurity.net), which boots on real hardware, will crash
on xen before even getting to the entry point.

By inspecting the memory of the running (crashed) kernel, most (if not all) of
the .data segment is filled with zeroes, thus making it die because the magic
is not "xen-3" (and this is because "xen-3" isn't there, just like the rest of
the constants)

The exact change in the PaX kernel that makes the dom die is in the file
arch/x86/kernel/vmlinux_32.lds.S, so i think (even if i'm not sure) that looks
like a problem with the relocation that Xen does when tries to load the domain

You can find all the info that i've discovered so far, including how to
reproduce the problem, in the thread i've started on grsecurity's forums:

http://forums.grsecurity.net/viewtopic.php?f=1&t=1913

(Please forgive me if i eventually made some mistakes in explaining xen-related
info, i'm quite new to Xen myself)

Thank you for your attention


-- 
Configure bugmail: 
http://bugzilla.xensource.com/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug, or are watching the assignee.

_______________________________________________
Xen-bugs mailing list
Xen-bugs@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-bugs