On Mon, Mar 29, 2021 at 06:07:30PM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> Currently the memory pointed to by area is being freed by the
> free_vm_area call and then area->nr_pages is referencing the
> free'd object. Fix this swapping the order of the warn_alloc
> message and the free.
>
> Addresses-Coverity: ("Read from pointer after free")
> Fixes: 014ccf9b888d ("mm/vmalloc: improve allocation failure error messages")
i don't have this git sha. if this is -next, the sha ids aren't stable
and shouldn't be referenced in commit logs, because these fixes should
just be squashed into the not-yet-upstream commits.
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> mm/vmalloc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index b73e4e715e0d..7936405749e4 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -2790,11 +2790,11 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
> }
>
> if (!pages) {
> - free_vm_area(area);
> warn_alloc(gfp_mask, NULL,
> "vmalloc size %lu allocation failure: "
> "page array size %lu allocation failed",
> area->nr_pages * PAGE_SIZE, array_size);
> + free_vm_area(area);
> return NULL;
this fix looks right to me.
