[Xen-devel] Ping: [PATCH 3/3] x86: tighten MMU_*PT_UPDATE* check and combine error paths

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 12.10.17 at 12:01,  wrote:
> Don't accept anything other than r/w RAM pages and move the paged-out
> check into the (unlikely) error path following that check.
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Ping?

> --- a/xen/arch/x86/mm.c
> +++ b/xen/arch/x86/mm.c
> @@ -3507,18 +3507,18 @@ long do_mmu_update(
>              gmfn = req.ptr >> PAGE_SHIFT;
>              page = get_page_from_gfn(pt_owner, gmfn, &p2mt, P2M_ALLOC);
>  
> -            if ( p2m_is_paged(p2mt) )
> +            if ( unlikely(!page) || p2mt != p2m_ram_rw )
>              {
> -                ASSERT(!page);
> -                p2m_mem_paging_populate(pt_owner, gmfn);
> -                rc = -ENOENT;
> -                break;
> -            }
> -
> -            if ( unlikely(!page) )
> -            {
> -                gdprintk(XENLOG_WARNING,
> -                         "Could not get page for normal update\n");
> +                if ( page )
> +                    put_page(page);
> +                if ( p2m_is_paged(p2mt) )
> +                {
> +                    p2m_mem_paging_populate(pt_owner, gmfn);
> +                    rc = -ENOENT;
> +                }
> +                else
> +                    gdprintk(XENLOG_WARNING,
> +                             "Could not get page for normal update\n");
>                  break;
>              }
>  
> 
> 
> 




_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel