[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <56CDFD8A.1040000@redhat.com>
Date: Wed, 24 Feb 2016 10:59:22 -0800
From: Laura Abbott <labbott@...hat.com>
To: Kees Cook <keescook@...omium.org>
Cc: Laura Abbott <labbott@...oraproject.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Arnd Bergmann <arnd@...db.de>,
"kernel-hardening@...ts.openwall.com" <kernel-hardening@...ts.openwall.com>,
LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCHv2] lkdtm: Add READ_AFTER_FREE test
On 02/23/2016 02:37 PM, Kees Cook wrote:
> On Tue, Feb 23, 2016 at 1:25 PM, Kees Cook <keescook@...omium.org> wrote:
>
>> zero poison only:
>> DEBUG_PAGEALLOC=n
>> PAGE_POISONING=y
>> PAGE_POISONING_NO_SANITY=y
>> PAGE_POISONING_ZERO=y
>> page_poison=on
>
> This combo (in next-20160223) results in an unusable system. :(
>
> [ 1.754183] random: init urandom read with 11 bits of entropy available
> [ 1.768449] hostname (1171) used greatest stack depth: 11808 bytes left
> [ 1.787954] BUG: Bad page map in process init pte:3d656c6f736e6f63
> pmd:00020067
> [ 1.789177] addr:00007f9f68200000 vm_flags:00000070 anon_vma:
> (null) mapping:ffff88007c314058 index:141
> [ 1.790564] file:libdl-2.19.so fault:ext4_filemap_fault
> mmap:ext4_file_mmap readpage:ext4_readpage
>
> -Kees
>
Hmmm, it looks like the -mm tree currently only has the v1 of the
poisoning patches and not the v2. The v1 had a bug which would
cause issues like this due to some pages not getting zeroed fully. I should
follow up on that today.
Thanks,
Laura
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
