diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2018-01-11 15:33:51 +0200 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2018-01-24 11:25:56 +0100 |
| commit | 24f0b17203691d22815e842051a014e3bde7c227 (patch) | |
| tree | b4a2a55684b6413ee380c1ac645831d2e3185ce3 /fs/overlayfs/namei.c | |
| parent | e7dd0e71348c1e3bc4b9d767c1ffbcbdee46a726 (diff) | |
ovl: whiteout orphan index entries on mount
Orphan index entries are non-dir index entries whose union nlink count
dropped to zero. With index=on, orphan index entries are removed on
mount. With NFS export feature enabled, orphan index entries are replaced
with white out index entries to block future open by handle from opening
the lower file.
When dir index has a stale 'upper' xattr, we assume that the upper dir
was removed and we treat the dir index as orphan entry that needs to be
whited out or removed.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/overlayfs/namei.c')
| -rw-r--r-- | fs/overlayfs/namei.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c index 7f27ec5999ea..111a64f904c2 100644 --- a/fs/overlayfs/namei.c +++ b/fs/overlayfs/namei.c @@ -539,7 +539,15 @@ int ovl_verify_index(struct ovl_fs *ofs, struct dentry *index) upper = ovl_index_upper(ofs, index); if (IS_ERR_OR_NULL(upper)) { err = PTR_ERR(upper); - if (!err) + /* + * Directory index entries with no 'upper' xattr need to be + * removed. When dir index entry has a stale 'upper' xattr, + * we assume that upper dir was removed and we treat the dir + * index as orphan entry that needs to be whited out. + */ + if (err == -ESTALE) + goto orphan; + else if (!err) err = -ESTALE; goto fail; } @@ -556,7 +564,7 @@ int ovl_verify_index(struct ovl_fs *ofs, struct dentry *index) goto fail; if (ovl_get_nlink(origin.dentry, index, 0) == 0) - err = -ENOENT; + goto orphan; } out: @@ -568,6 +576,13 @@ fail: pr_warn_ratelimited("overlayfs: failed to verify index (%pd2, ftype=%x, err=%i)\n", index, d_inode(index)->i_mode & S_IFMT, err); goto out; + +orphan: + pr_warn_ratelimited("overlayfs: orphan index entry (%pd2, ftype=%x, nlink=%u)\n", + index, d_inode(index)->i_mode & S_IFMT, + d_inode(index)->i_nlink); + err = -ENOENT; + goto out; } /* |