On 2/9/22 05:40, liuyuntao wrote:
> From: Liu Yuntao <liuyuntao10@xxxxxxxxxx>
>
> When we specify a large number for node in hugepages parameter,
> it may be parsed to another number due to truncation in this statement:
> node = tmp;
>
> For example, add following parameter in command line:
> hugepagesz=1G hugepages=4294967297:5
> and kernel will allocate 5 hugepages for node 1 instead of ignoring it.
>
> I move the validation check earlier to fix this issue, and slightly
> simplifies the condition here.
>
> Fixes: b5389086ad7be0 ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
> Signed-off-by: Liu Yuntao <liuyuntao10@xxxxxxxxxx>
> ---
> mm/hugetlb.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 61895cc01d09..0929547f6ad6 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -4159,10 +4159,10 @@ static int __init hugepages_setup(char *s)
> pr_warn("HugeTLB: architecture can't support node specific alloc, ignoring!\n");
> return 0;
> }
> + if (tmp >= nr_online_nodes)
> + goto invalid;
> node = tmp;
I am surprised none of the automated checking complained about that
assignment.
> p += count + 1;
> - if (node < 0 || node >= nr_online_nodes)
I can't remember, but I think that check for node < 0 was added to handle
overflow during the above assignment. Do you remember Zhenguo Yao?
> - goto invalid;
> /* Parse hugepages */
> if (sscanf(p, "%lu%n", &tmp, &count) != 1)
> goto invalid;
Thanks,
Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
--
Mike Kravetz
