Re: [Qemu-devel] [Bug 1332297] Re: qemu-img: crash on check of an image with large value in the 'size' header field

[M.Kustova]

On Wed, Jun 25, 2014 at 2:40 PM, Kevin Wolf <address@hidden> wrote:
> Am 25.06.2014 um 11:54 hat M.Kustova geschrieben:
>> On Wed, Jun 25, 2014 at 1:42 PM, Kevin Wolf <address@hidden> wrote:
>> > Am 25.06.2014 um 11:32 hat M.Kustova geschrieben:
>> >> On Tue, Jun 24, 2014 at 7:36 PM, Kevin Wolf <address@hidden> wrote:
>> >> > Am 24.06.2014 um 15:19 hat M.Kustova geschrieben:
>> >> >> On Mon, Jun 23, 2014 at 12:02 PM, Stefan Hajnoczi <address@hidden> 
>> >> >> wrote:
>> >> >> > On Thu, Jun 19, 2014 at 07:19:55PM -0000, Maria Kustova wrote:
>> >> >> >> The bug description missed qemu-img error:
>> >> >> >>
>> >> >> >> (process:12283): GLib-ERROR **: gmem.c:110: failed to allocate
>> >> >> >> 18446744059294601304 bytes
>> >> >> >
>> >> >> > Thanks, there has been recent work by Kevin Wolf to handle memory
>> >> >> > allocation failures gracefully without terminating QEMU.  This sounds
>> >> >> > like a candidate for g_try_malloc() and friends.
>> >> >> >
>> >> >> > Does the following patch series solve the problem?
>> >> >> > https://lists.gnu.org/archive/html/qemu-devel/2014-06/msg01275.html
>> >> >>
>> >> >> These patches are conflicting with current master. So I can't test
>> >> >> them as they are.
>> >> >>
>> >> >> Do you have a developer repository or branch containing these patches,
>> >> >> so I could test it on the pre-release base?
>> >> >
>> >> > I'm just about to send a new version, I'll keep you CCed there.
>> >>
>> >> "[PATCH v4 21/21] qcow2: Return useful error code in refcount_init()"
>> >> is still broken for the current master.
>> >
>> > In which way? I can cleanly apply the whole patch series on master (even
>> > tried applying the emails from my inbox to be sure).
>>
>> Beginning from line #49 in master:
>>
>>     if (s->refcount_table_size > 0) {
>>         BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD);
>>         ret = bdrv_pread(bs->file, s->refcount_table_offset,
>>
>> The patch:
>>
>>    if (s->refcount_table_size > 0) {^M
>>          if (s->refcount_table == NULL) {^M
>> +            ret = -ENOMEM;^M
>>              goto fail;^M
>>          }^M
>>          BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD);^M
>>          ret = bdrv_pread(bs->file, s->refcount_table_offset,^M
>>
>> At least master version doesn't have this condition.
>
> It is code added in patch 11 of the same series.

My apologies for the false alarm.

>
> Kevin
Maria