Re: [PATCH] ovl: bump the impure dir version when linking a file with origin

[Amir Goldstein]

On Thu, Nov 12, 2026 at 4:58 AM Daejun Park via B4 Relay
<devnull+daejun7.park.samsung.com@xxxxxxxxxx> wrote:
>
> From: Daejun Park <daejun7.park@xxxxxxxxxxx>
>
> Linking a file with copy up origin into a non-merge impure dir does
> not bump the dir version. readdir then reuses the impure dir cache
> built before the link. It reports the upper inode number as d_ino of
> the new link, not st_ino.
>
> Pass whether the linked file has an origin to ovl_dir_modified(), as
> rename and unlink do.
>
> Fixes: 4edb83bb1041 ("ovl: constant d_ino for non-merge dirs")
> Reported-by: Sashiko <sashiko-bot@xxxxxxxxxx>
> Closes: https://sashiko.dev/#/bug/linux-98f207b6-3936-48e9-a40f-88f20be4db7b
> Signed-off-by: Daejun Park <daejun7.park@xxxxxxxxxxx>

Applied.

Thanks for taking care of this!
Amir.

> ---
> Tested on ext4 and xfs with default overlay options: the new fstests
> test overlay/013 fails without this patch and passes with it. So does
> a script that puts a whiteout in a non-merge upper dir before mount
> and links over it (ovl_create_over_whiteout()). Apart from
> overlay/013, only 079, 085 and 088 fail in overlay/auto on ovl-fixes,
> with and without this patch.

FYI:

https://lore.kernel.org/linux-unionfs/20261111132836.3495981-1-giuseppe@xxxxxxxxxxxx/

> ---
>  fs/overlayfs/dir.c | 20 +++++++++++---------
>  1 file changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
> index e0a164e22d67..8fec18dc5fc7 100644
> --- a/fs/overlayfs/dir.c
> +++ b/fs/overlayfs/dir.c
> @@ -368,7 +368,7 @@ static bool ovl_type_origin(struct dentry *dentry)
>  }
>
>  static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
> -                           struct ovl_cattr *attr)
> +                           struct ovl_cattr *attr, bool origin)
>  {
>         struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
>         struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
> @@ -393,7 +393,7 @@ static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
>                 ovl_set_opaque(dentry, newdentry);
>         }
>
> -       ovl_dir_modified(dentry->d_parent, false);
> +       ovl_dir_modified(dentry->d_parent, origin);
>         err = ovl_instantiate(dentry, inode, newdentry, !!attr->hardlink, NULL);
>         if (err)
>                 goto out_cleanup;
> @@ -491,7 +491,7 @@ static int ovl_set_upper_acl(struct ovl_fs *ofs, struct dentry *upperdentry,
>  }
>
>  static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
> -                                   struct ovl_cattr *cattr)
> +                                   struct ovl_cattr *cattr, bool origin)
>  {
>         struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
>         struct dentry *workdir = ovl_workdir(dentry);
> @@ -582,7 +582,7 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
>                 if (err)
>                         goto out_cleanup_unlocked;
>         }
> -       ovl_dir_modified(dentry->d_parent, false);
> +       ovl_dir_modified(dentry->d_parent, origin);
>         err = ovl_instantiate(dentry, inode, newdentry, hardlink, NULL);
>         if (err) {
>                 ovl_cleanup(ofs, upperdir, newdentry);
> @@ -647,12 +647,12 @@ DEFINE_CLASS(ovl_override_creator_creds,
>
>  static int ovl_create_handle_whiteouts(struct dentry *dentry,
>                                        struct inode *inode,
> -                                      struct ovl_cattr *attr)
> +                                      struct ovl_cattr *attr, bool origin)
>  {
>         if (!ovl_dentry_is_whiteout(dentry))
> -               return ovl_create_upper(dentry, inode, attr);
> +               return ovl_create_upper(dentry, inode, attr, origin);
>
> -       return ovl_create_over_whiteout(dentry, inode, attr);
> +       return ovl_create_over_whiteout(dentry, inode, attr, origin);
>  }
>
>  static int ovl_create_or_link(struct dentry *dentry, struct inode *inode,
> @@ -687,12 +687,14 @@ static int ovl_create_or_link(struct dentry *dentry, struct inode *inode,
>                  */
>
>                 if (attr->hardlink)
> -                       return ovl_create_handle_whiteouts(dentry, inode, attr);
> +                       return ovl_create_handle_whiteouts(dentry, inode, attr,
> +                                                          origin);
>
>                 scoped_class(ovl_override_creator_creds, cred, original_creds, dentry, inode, attr->mode) {
>                         if (IS_ERR(cred))
>                                 return PTR_ERR(cred);
> -                       return ovl_create_handle_whiteouts(dentry, inode, attr);
> +                       return ovl_create_handle_whiteouts(dentry, inode, attr,
> +                                                          origin);
>                 }
>         }
>         return err;
>
> ---
> base-commit: 0d5e729c515f4ae4eacc179dbcf350d9b499a161
> change-id: 20261112-ovl-link-impure-8624810156d8
>
> Best regards,
> --
> Daejun Park <daejun7.park@xxxxxxxxxxx>
>
>