[PATCH] malloc: Do not make out-of-bounds madvise call on non-aligned heap

[Wilco Dijkstra]

Hi Dev,

OK - committed.

Reviewed-by: Wilco Dijkstra  <Wilco.Dijkstra@arm.com>

Cheers,
Wilco


> +++ b/malloc/malloc.c
> @@ -2071,8 +2071,8 @@ madvise_thp (void *p, INTERNAL_SIZE_T size)
>        inputs happens only for initial data segment.  */
>     if (__glibc_unlikely (!PTR_IS_ALIGNED (p, GLRO (dl_pagesize))))
>       {
> -      void *q = PTR_ALIGN_DOWN (p, GLRO (dl_pagesize));
> -      size += PTR_DIFF (p, q);
> +      void *q = PTR_ALIGN_UP (p, GLRO (dl_pagesize));
> +      size -= PTR_DIFF (q, p);
>         p = q;
>       }
>