---- 在 星期二, 2019-10-29 05:27:01 Mike Kravetz <mike.kravetz@xxxxxxxxxx> 撰写 ----
> On 10/17/19 3:38 AM, Chengguang Xu wrote:
> > In order to avoid using incorrect mnt, we should set
> > mnt to NULL when we get error from mount_one_hugetlbfs().
> >
> > Signed-off-by: Chengguang Xu <cgxu519@xxxxxxxxxxxx>
>
> Thanks for noticing this issue. As mentioned in a previous e-mail,
> there are additional issues that need to be addressed. This loop
> needs to initialize entries in the hugetlbfs_vfsmount array for all
> hstates. How about this patch?
>
> From 3144f0a9d18f1408e831fb3eb49a06636a11d902 Mon Sep 17 00:00:00 2001
> From: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
> Date: Mon, 28 Oct 2019 14:08:42 -0700
> Subject: [PATCH] mm/hugetlbfs: fix error handling when setting up mounts
>
> It is assumed that the hugetlbfs_vfsmount[] array will contain
> either a valid vfsmount pointer or NULL for each hstate after
> initialization. Changes made while converting to use fs_context
> broke this assumption.
>
> Reported-by: Chengguang Xu <cgxu519@xxxxxxxxxxxx>
> Fixes: 32021982a324 ("hugetlbfs: Convert to fs_context")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
> ---
> fs/hugetlbfs/inode.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
> index a478df035651..178389209561 100644
> --- a/fs/hugetlbfs/inode.c
> +++ b/fs/hugetlbfs/inode.c
> @@ -1470,15 +1470,17 @@ static int __init init_hugetlbfs_fs(void)
> i = 0;
> for_each_hstate(h) {
> mnt = mount_one_hugetlbfs(h);
> - if (IS_ERR(mnt) && i == 0) {
> + if (IS_ERR(mnt)) {
> + hugetlbfs_vfsmount[i] = NULL;
> error = PTR_ERR(mnt);
> - goto out;
> + } else {
> + hugetlbfs_vfsmount[i] = mnt;
> }
> - hugetlbfs_vfsmount[i] = mnt;
> i++;
> }
>
> - return 0;
> + if (hugetlbfs_vfsmount[default_hstate_idx] != NULL)
> + return 0;
Maybe we should umount other non-null entries and release
used inodes for safety in error case.
Thanks,
Chengguang
>
> out:
> kmem_cache_destroy(hugetlbfs_inode_cachep);
> --
> 2.20.1
>
>
