Re: [Qemu-devel] [PATCH 0/7] qcow2 check improvements

[Vladimir Sementsov-Ogievskiy]

ping

Hi, what about this?

17.08.2018 15:22, Vladimir Sementsov-Ogievskiy wrote:
> Hi all!
>
> v2:
> 02, 06: check bdrv_getlength error return code
>
> v1:
>
> We've faced the following problem: after host fs corruption, vm images
> becomes invalid. And which is interesting, starting qemu-img check on
> them led to allocating of the whole RAM and then killing qemu-img by
> OOM Killer.
>
> This was due to corrupted l2 entries, which referenced clusters far-far
> beyond the end of the qcow2 file.
> 02 is a generic fix for the bug, 01 is unrelated improvement, 03-07 are
> additional info and fixing for such corrupted table entries.
>
> Questions on 02, 06 and 07:
> 1. Should restrictions be more or less strict?
> 2. Are there valid cases, when such entries should not be considered as
>     corrupted?
>
> Vladimir Sementsov-Ogievskiy (7):
>    block/qcow2-refcount: fix check_oflag_copied
>    block/qcow2-refcount: avoid eating RAM
>    block/qcow2-refcount: check_refcounts_l2: refactor compressed case
>    block/qcow2-refcount: check_refcounts_l2: reduce ignored overlaps
>    block/qcow2-refcount: check_refcounts_l2: split fix_l2_entry_to_zero
>    block/qcow2-refcount: fix out-of-file L1 entries to be zero
>    block/qcow2-refcount: fix out-of-file L2 entries to be read-as-zero
>
>   block/qcow2-refcount.c | 270 
> +++++++++++++++++++++++++++++++++++++++----------
>   1 file changed, 219 insertions(+), 51 deletions(-)
>


-- 
Best regards,
Vladimir