Re: [PATCH 4.4 00/24] 4.4.137-stable review

[Rafael David Tinoco]

On Wed, Jun 13, 2018 at 6:00 PM, Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Wed, Jun 13, 2018 at 05:47:49PM -0300, Rafael Tinoco wrote:
>> Results from Linaroâs test farm.
>> Regressions detected.
>>
>> NOTE:
>>
>> 1) LTP vma03 test (cve-2011-2496) broken on v4.4-137-rc1 because of:
>>
>>      6ea1dc96a03a mmap: relax file size limit for regular files
>>      bd2f9ce5bacb mmap: introduce sane default mmap limits
>>
>>    discussion:
>>
>>      https://github.com/linux-test-project/ltp/issues/341
>>
>>    mainline commit (v4.13-rc7):
>>
>>      0cc3b0ec23ce Clarify (and fix) MAX_LFS_FILESIZE macros
>>
>>    should be backported to 4.4.138-rc2 and fixes the issue.
>
> Really?  That commit says it fixes c2a9737f45e2 ("vfs,mm: fix a dead
> loop in truncate_inode_pages_range()") which is not in 4.4.y at all.
>
> Did you test this out?

Yes, the LTP contains the tests (last comment is the final test for
arm32, right before Jan tests i686).

Fixing MAX_LFS_FILESIZE fixes the new limit for mmap() brought by
those 2 commits (file_mmap_size_max()).
offset tested by the LTP test is 0xfffffffe000.
file_mmap_size_max gives: 0xFFFFFFFF000 as max value, but only after
the mentioned patch.

Original intent for this fix was other though.

> thanks,
>
> greg k-h