Re: [PATCH v2 01/20] parallels: Set s->used_bmap to NULL in parallels_free_used_bitmap()

[Alexander Ivanov]

On 10/21/23 12:40, Mike Maslenkin wrote:
> On Thu, Oct 19, 2023 at 4:06 PM Alexander Ivanov
> <alexander.ivanov@virtuozzo.com> wrote:
> > After used bitmap freeng s->used_bmap points to the freed memory. If we try
> > to free used bitmap one more time it leads to double free error.
> >
> > Set s->used_bmap to NULL to exclude double free error.
> >
> > Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
> > ---
> >   block/parallels.c | 1 +
> >   1 file changed, 1 insertion(+)
> >
> > diff --git a/block/parallels.c b/block/parallels.c
> > index 6b46623241..ba1fdde259 100644
> > --- a/block/parallels.c
> > +++ b/block/parallels.c
> > @@ -244,6 +244,7 @@ static void parallels_free_used_bitmap(BlockDriverState *bs)
> >   {
> >       BDRVParallelsState *s = bs->opaque;
> >       s->used_bmap_size = 0;
> > +    s->used_bmap = NULL;
> >       g_free(s->used_bmap);
> >   }
> Shouldn't it be added after g_free() call?
OMG, of course.
> Regards,
> Mike.

--
Best regards,
Alexander Ivanov