diff options
Diffstat (limited to 'fs/overlayfs/dir.c')
| -rw-r--r-- | fs/overlayfs/dir.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index dbd63a74df4b..a5e9ddf3023b 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -187,6 +187,13 @@ struct dentry *ovl_create_real(struct ovl_fs *ofs, struct dentry *parent, /* mkdir is special... */ newdentry = ovl_do_mkdir(ofs, dir, newdentry, attr->mode); err = PTR_ERR_OR_ZERO(newdentry); + /* expect to inherit casefolding from workdir/upperdir */ + if (!err && ofs->casefold != ovl_dentry_casefolded(newdentry)) { + pr_warn_ratelimited("wrong inherited casefold (%pd2)\n", + newdentry); + dput(newdentry); + err = -EINVAL; + } break; case S_IFCHR: @@ -205,12 +212,32 @@ struct dentry *ovl_create_real(struct ovl_fs *ofs, struct dentry *parent, err = -EPERM; } } - if (!err && WARN_ON(!newdentry->d_inode)) { + if (err) + goto out; + + if (WARN_ON(!newdentry->d_inode)) { /* * Not quite sure if non-instantiated dentry is legal or not. * VFS doesn't seem to care so check and warn here. */ err = -EIO; + } else if (d_unhashed(newdentry)) { + struct dentry *d; + /* + * Some filesystems (i.e. casefolded) may return an unhashed + * negative dentry from the ovl_lookup_upper() call before + * ovl_create_real(). + * In that case, lookup again after making the newdentry + * positive, so ovl_create_upper() always returns a hashed + * positive dentry. + */ + d = ovl_lookup_upper(ofs, newdentry->d_name.name, parent, + newdentry->d_name.len); + dput(newdentry); + if (IS_ERR_OR_NULL(d)) + err = d ? PTR_ERR(d) : -ENOENT; + else + return d; } out: if (err) { |