![Amir Goldstein](/assets/img/avatar_default.png)
Fixes: 359f392ca5
("ovl: lookup index entry for copy up origin")
Cc: <stable@vger.kernel.org> # v4.13
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
799 lines
18 KiB
C
799 lines
18 KiB
C
/*
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* Copyright (C) 2011 Novell Inc.
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* Copyright (C) 2016 Red Hat, Inc.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 as published by
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* the Free Software Foundation.
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*/
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#include <linux/fs.h>
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#include <linux/cred.h>
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#include <linux/namei.h>
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#include <linux/xattr.h>
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#include <linux/ratelimit.h>
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#include <linux/mount.h>
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#include <linux/exportfs.h>
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#include "overlayfs.h"
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#include "ovl_entry.h"
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struct ovl_lookup_data {
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struct qstr name;
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bool is_dir;
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bool opaque;
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bool stop;
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bool last;
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char *redirect;
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};
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static int ovl_check_redirect(struct dentry *dentry, struct ovl_lookup_data *d,
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size_t prelen, const char *post)
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{
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int res;
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char *s, *next, *buf = NULL;
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res = vfs_getxattr(dentry, OVL_XATTR_REDIRECT, NULL, 0);
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if (res < 0) {
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if (res == -ENODATA || res == -EOPNOTSUPP)
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return 0;
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goto fail;
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}
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buf = kzalloc(prelen + res + strlen(post) + 1, GFP_KERNEL);
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if (!buf)
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return -ENOMEM;
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if (res == 0)
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goto invalid;
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res = vfs_getxattr(dentry, OVL_XATTR_REDIRECT, buf, res);
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if (res < 0)
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goto fail;
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if (res == 0)
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goto invalid;
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if (buf[0] == '/') {
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for (s = buf; *s++ == '/'; s = next) {
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next = strchrnul(s, '/');
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if (s == next)
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goto invalid;
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}
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} else {
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if (strchr(buf, '/') != NULL)
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goto invalid;
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memmove(buf + prelen, buf, res);
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memcpy(buf, d->name.name, prelen);
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}
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strcat(buf, post);
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kfree(d->redirect);
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d->redirect = buf;
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d->name.name = d->redirect;
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d->name.len = strlen(d->redirect);
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return 0;
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err_free:
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kfree(buf);
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return 0;
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fail:
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pr_warn_ratelimited("overlayfs: failed to get redirect (%i)\n", res);
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goto err_free;
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invalid:
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pr_warn_ratelimited("overlayfs: invalid redirect (%s)\n", buf);
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goto err_free;
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}
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static int ovl_acceptable(void *ctx, struct dentry *dentry)
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{
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return 1;
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}
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static struct ovl_fh *ovl_get_origin_fh(struct dentry *dentry)
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{
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int res;
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struct ovl_fh *fh = NULL;
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res = vfs_getxattr(dentry, OVL_XATTR_ORIGIN, NULL, 0);
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if (res < 0) {
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if (res == -ENODATA || res == -EOPNOTSUPP)
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return NULL;
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goto fail;
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}
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/* Zero size value means "copied up but origin unknown" */
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if (res == 0)
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return NULL;
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fh = kzalloc(res, GFP_KERNEL);
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if (!fh)
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return ERR_PTR(-ENOMEM);
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res = vfs_getxattr(dentry, OVL_XATTR_ORIGIN, fh, res);
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if (res < 0)
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goto fail;
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if (res < sizeof(struct ovl_fh) || res < fh->len)
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goto invalid;
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if (fh->magic != OVL_FH_MAGIC)
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goto invalid;
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/* Treat larger version and unknown flags as "origin unknown" */
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if (fh->version > OVL_FH_VERSION || fh->flags & ~OVL_FH_FLAG_ALL)
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goto out;
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/* Treat endianness mismatch as "origin unknown" */
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if (!(fh->flags & OVL_FH_FLAG_ANY_ENDIAN) &&
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(fh->flags & OVL_FH_FLAG_BIG_ENDIAN) != OVL_FH_FLAG_CPU_ENDIAN)
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goto out;
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return fh;
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out:
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kfree(fh);
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return NULL;
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fail:
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pr_warn_ratelimited("overlayfs: failed to get origin (%i)\n", res);
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goto out;
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invalid:
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pr_warn_ratelimited("overlayfs: invalid origin (%*phN)\n", res, fh);
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goto out;
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}
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static struct dentry *ovl_get_origin(struct dentry *dentry,
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struct vfsmount *mnt)
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{
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struct dentry *origin = NULL;
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struct ovl_fh *fh = ovl_get_origin_fh(dentry);
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int bytes;
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if (IS_ERR_OR_NULL(fh))
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return (struct dentry *)fh;
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/*
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* Make sure that the stored uuid matches the uuid of the lower
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* layer where file handle will be decoded.
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*/
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if (!uuid_equal(&fh->uuid, &mnt->mnt_sb->s_uuid))
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goto out;
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bytes = (fh->len - offsetof(struct ovl_fh, fid));
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origin = exportfs_decode_fh(mnt, (struct fid *)fh->fid,
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bytes >> 2, (int)fh->type,
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ovl_acceptable, NULL);
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if (IS_ERR(origin)) {
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/* Treat stale file handle as "origin unknown" */
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if (origin == ERR_PTR(-ESTALE))
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origin = NULL;
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goto out;
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}
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if (ovl_dentry_weird(origin) ||
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((d_inode(origin)->i_mode ^ d_inode(dentry)->i_mode) & S_IFMT))
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goto invalid;
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out:
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kfree(fh);
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return origin;
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invalid:
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pr_warn_ratelimited("overlayfs: invalid origin (%pd2)\n", origin);
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dput(origin);
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origin = NULL;
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goto out;
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}
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static bool ovl_is_opaquedir(struct dentry *dentry)
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{
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return ovl_check_dir_xattr(dentry, OVL_XATTR_OPAQUE);
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}
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static int ovl_lookup_single(struct dentry *base, struct ovl_lookup_data *d,
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const char *name, unsigned int namelen,
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size_t prelen, const char *post,
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struct dentry **ret)
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{
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struct dentry *this;
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int err;
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this = lookup_one_len_unlocked(name, base, namelen);
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if (IS_ERR(this)) {
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err = PTR_ERR(this);
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this = NULL;
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if (err == -ENOENT || err == -ENAMETOOLONG)
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goto out;
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goto out_err;
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}
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if (!this->d_inode)
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goto put_and_out;
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if (ovl_dentry_weird(this)) {
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/* Don't support traversing automounts and other weirdness */
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err = -EREMOTE;
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goto out_err;
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}
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if (ovl_is_whiteout(this)) {
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d->stop = d->opaque = true;
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goto put_and_out;
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}
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if (!d_can_lookup(this)) {
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d->stop = true;
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if (d->is_dir)
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goto put_and_out;
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goto out;
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}
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d->is_dir = true;
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if (!d->last && ovl_is_opaquedir(this)) {
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d->stop = d->opaque = true;
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goto out;
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}
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err = ovl_check_redirect(this, d, prelen, post);
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if (err)
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goto out_err;
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out:
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*ret = this;
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return 0;
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put_and_out:
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dput(this);
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this = NULL;
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goto out;
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out_err:
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dput(this);
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return err;
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}
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static int ovl_lookup_layer(struct dentry *base, struct ovl_lookup_data *d,
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struct dentry **ret)
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{
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/* Counting down from the end, since the prefix can change */
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size_t rem = d->name.len - 1;
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struct dentry *dentry = NULL;
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int err;
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if (d->name.name[0] != '/')
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return ovl_lookup_single(base, d, d->name.name, d->name.len,
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0, "", ret);
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while (!IS_ERR_OR_NULL(base) && d_can_lookup(base)) {
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const char *s = d->name.name + d->name.len - rem;
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const char *next = strchrnul(s, '/');
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size_t thislen = next - s;
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bool end = !next[0];
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/* Verify we did not go off the rails */
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if (WARN_ON(s[-1] != '/'))
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return -EIO;
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err = ovl_lookup_single(base, d, s, thislen,
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d->name.len - rem, next, &base);
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dput(dentry);
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if (err)
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return err;
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dentry = base;
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if (end)
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break;
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rem -= thislen + 1;
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if (WARN_ON(rem >= d->name.len))
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return -EIO;
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}
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*ret = dentry;
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return 0;
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}
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static int ovl_check_origin(struct dentry *upperdentry,
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struct path *lowerstack, unsigned int numlower,
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struct path **stackp, unsigned int *ctrp)
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{
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struct vfsmount *mnt;
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struct dentry *origin = NULL;
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int i;
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for (i = 0; i < numlower; i++) {
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mnt = lowerstack[i].mnt;
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origin = ovl_get_origin(upperdentry, mnt);
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if (IS_ERR(origin))
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return PTR_ERR(origin);
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if (origin)
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break;
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}
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if (!origin)
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return 0;
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BUG_ON(*ctrp);
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if (!*stackp)
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*stackp = kmalloc(sizeof(struct path), GFP_KERNEL);
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if (!*stackp) {
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dput(origin);
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return -ENOMEM;
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}
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**stackp = (struct path) { .dentry = origin, .mnt = mnt };
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*ctrp = 1;
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return 0;
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}
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/*
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* Verify that @fh matches the origin file handle stored in OVL_XATTR_ORIGIN.
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* Return 0 on match, -ESTALE on mismatch, < 0 on error.
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*/
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static int ovl_verify_origin_fh(struct dentry *dentry, const struct ovl_fh *fh)
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{
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struct ovl_fh *ofh = ovl_get_origin_fh(dentry);
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int err = 0;
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if (!ofh)
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return -ENODATA;
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if (IS_ERR(ofh))
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return PTR_ERR(ofh);
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if (fh->len != ofh->len || memcmp(fh, ofh, fh->len))
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err = -ESTALE;
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kfree(ofh);
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return err;
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}
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/*
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* Verify that an inode matches the origin file handle stored in upper inode.
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*
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* If @set is true and there is no stored file handle, encode and store origin
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* file handle in OVL_XATTR_ORIGIN.
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*
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* Return 0 on match, -ESTALE on mismatch, < 0 on error.
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*/
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int ovl_verify_origin(struct dentry *dentry, struct vfsmount *mnt,
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struct dentry *origin, bool is_upper, bool set)
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{
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struct inode *inode;
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struct ovl_fh *fh;
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int err;
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fh = ovl_encode_fh(origin, is_upper);
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err = PTR_ERR(fh);
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if (IS_ERR(fh))
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goto fail;
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err = ovl_verify_origin_fh(dentry, fh);
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if (set && err == -ENODATA)
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err = ovl_do_setxattr(dentry, OVL_XATTR_ORIGIN, fh, fh->len, 0);
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if (err)
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goto fail;
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out:
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kfree(fh);
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return err;
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fail:
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inode = d_inode(origin);
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pr_warn_ratelimited("overlayfs: failed to verify origin (%pd2, ino=%lu, err=%i)\n",
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origin, inode ? inode->i_ino : 0, err);
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goto out;
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}
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/*
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* Verify that an index entry name matches the origin file handle stored in
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* OVL_XATTR_ORIGIN and that origin file handle can be decoded to lower path.
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* Return 0 on match, -ESTALE on mismatch or stale origin, < 0 on error.
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*/
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int ovl_verify_index(struct dentry *index, struct path *lowerstack,
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unsigned int numlower)
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{
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struct ovl_fh *fh = NULL;
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size_t len;
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struct path origin = { };
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struct path *stack = &origin;
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unsigned int ctr = 0;
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int err;
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if (!d_inode(index))
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return 0;
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/*
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* Directory index entries are going to be used for looking up
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* redirected upper dirs by lower dir fh when decoding an overlay
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* file handle of a merge dir. Whiteout index entries are going to be
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* used as an indication that an exported overlay file handle should
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* be treated as stale (i.e. after unlink of the overlay inode).
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* We don't know the verification rules for directory and whiteout
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* index entries, because they have not been implemented yet, so return
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* EROFS if those entries are found to avoid corrupting an index that
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* was created by a newer kernel.
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*/
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err = -EROFS;
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if (d_is_dir(index) || ovl_is_whiteout(index))
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goto fail;
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err = -EINVAL;
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if (index->d_name.len < sizeof(struct ovl_fh)*2)
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goto fail;
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err = -ENOMEM;
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len = index->d_name.len / 2;
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fh = kzalloc(len, GFP_KERNEL);
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if (!fh)
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goto fail;
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err = -EINVAL;
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if (hex2bin((u8 *)fh, index->d_name.name, len) || len != fh->len)
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goto fail;
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err = ovl_verify_origin_fh(index, fh);
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if (err)
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goto fail;
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err = ovl_check_origin(index, lowerstack, numlower, &stack, &ctr);
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if (!err && !ctr)
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err = -ESTALE;
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if (err)
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goto fail;
|
|
|
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/* Check if index is orphan and don't warn before cleaning it */
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if (d_inode(index)->i_nlink == 1 &&
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ovl_get_nlink(index, origin.dentry, 0) == 0)
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err = -ENOENT;
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|
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dput(origin.dentry);
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out:
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kfree(fh);
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return err;
|
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|
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fail:
|
|
pr_warn_ratelimited("overlayfs: failed to verify index (%pd2, ftype=%x, err=%i)\n",
|
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index, d_inode(index)->i_mode & S_IFMT, err);
|
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goto out;
|
|
}
|
|
|
|
/*
|
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* Lookup in indexdir for the index entry of a lower real inode or a copy up
|
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* origin inode. The index entry name is the hex representation of the lower
|
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* inode file handle.
|
|
*
|
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* If the index dentry in negative, then either no lower aliases have been
|
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* copied up yet, or aliases have been copied up in older kernels and are
|
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* not indexed.
|
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*
|
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* If the index dentry for a copy up origin inode is positive, but points
|
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* to an inode different than the upper inode, then either the upper inode
|
|
* has been copied up and not indexed or it was indexed, but since then
|
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* index dir was cleared. Either way, that index cannot be used to indentify
|
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* the overlay inode.
|
|
*/
|
|
int ovl_get_index_name(struct dentry *origin, struct qstr *name)
|
|
{
|
|
int err;
|
|
struct ovl_fh *fh;
|
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char *n, *s;
|
|
|
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fh = ovl_encode_fh(origin, false);
|
|
if (IS_ERR(fh))
|
|
return PTR_ERR(fh);
|
|
|
|
err = -ENOMEM;
|
|
n = kzalloc(fh->len * 2, GFP_KERNEL);
|
|
if (n) {
|
|
s = bin2hex(n, fh, fh->len);
|
|
*name = (struct qstr) QSTR_INIT(n, s - n);
|
|
err = 0;
|
|
}
|
|
kfree(fh);
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
static struct dentry *ovl_lookup_index(struct dentry *dentry,
|
|
struct dentry *upper,
|
|
struct dentry *origin)
|
|
{
|
|
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
|
struct dentry *index;
|
|
struct inode *inode;
|
|
struct qstr name;
|
|
int err;
|
|
|
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err = ovl_get_index_name(origin, &name);
|
|
if (err)
|
|
return ERR_PTR(err);
|
|
|
|
index = lookup_one_len_unlocked(name.name, ofs->indexdir, name.len);
|
|
if (IS_ERR(index)) {
|
|
err = PTR_ERR(index);
|
|
pr_warn_ratelimited("overlayfs: failed inode index lookup (ino=%lu, key=%*s, err=%i);\n"
|
|
"overlayfs: mount with '-o index=off' to disable inodes index.\n",
|
|
d_inode(origin)->i_ino, name.len, name.name,
|
|
err);
|
|
goto out;
|
|
}
|
|
|
|
inode = d_inode(index);
|
|
if (d_is_negative(index)) {
|
|
if (upper && d_inode(origin)->i_nlink > 1) {
|
|
pr_warn_ratelimited("overlayfs: hard link with origin but no index (ino=%lu).\n",
|
|
d_inode(origin)->i_ino);
|
|
goto fail;
|
|
}
|
|
|
|
dput(index);
|
|
index = NULL;
|
|
} else if (upper && d_inode(upper) != inode) {
|
|
pr_warn_ratelimited("overlayfs: wrong index found (index=%pd2, ino=%lu, upper ino=%lu).\n",
|
|
index, inode->i_ino, d_inode(upper)->i_ino);
|
|
goto fail;
|
|
} else if (ovl_dentry_weird(index) || ovl_is_whiteout(index) ||
|
|
((inode->i_mode ^ d_inode(origin)->i_mode) & S_IFMT)) {
|
|
/*
|
|
* Index should always be of the same file type as origin
|
|
* except for the case of a whiteout index. A whiteout
|
|
* index should only exist if all lower aliases have been
|
|
* unlinked, which means that finding a lower origin on lookup
|
|
* whose index is a whiteout should be treated as an error.
|
|
*/
|
|
pr_warn_ratelimited("overlayfs: bad index found (index=%pd2, ftype=%x, origin ftype=%x).\n",
|
|
index, d_inode(index)->i_mode & S_IFMT,
|
|
d_inode(origin)->i_mode & S_IFMT);
|
|
goto fail;
|
|
}
|
|
|
|
out:
|
|
kfree(name.name);
|
|
return index;
|
|
|
|
fail:
|
|
dput(index);
|
|
index = ERR_PTR(-EIO);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Returns next layer in stack starting from top.
|
|
* Returns -1 if this is the last layer.
|
|
*/
|
|
int ovl_path_next(int idx, struct dentry *dentry, struct path *path)
|
|
{
|
|
struct ovl_entry *oe = dentry->d_fsdata;
|
|
|
|
BUG_ON(idx < 0);
|
|
if (idx == 0) {
|
|
ovl_path_upper(dentry, path);
|
|
if (path->dentry)
|
|
return oe->numlower ? 1 : -1;
|
|
idx++;
|
|
}
|
|
BUG_ON(idx > oe->numlower);
|
|
*path = oe->lowerstack[idx - 1];
|
|
|
|
return (idx < oe->numlower) ? idx + 1 : -1;
|
|
}
|
|
|
|
struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
|
|
unsigned int flags)
|
|
{
|
|
struct ovl_entry *oe;
|
|
const struct cred *old_cred;
|
|
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
|
struct ovl_entry *poe = dentry->d_parent->d_fsdata;
|
|
struct ovl_entry *roe = dentry->d_sb->s_root->d_fsdata;
|
|
struct path *stack = NULL;
|
|
struct dentry *upperdir, *upperdentry = NULL;
|
|
struct dentry *index = NULL;
|
|
unsigned int ctr = 0;
|
|
struct inode *inode = NULL;
|
|
bool upperopaque = false;
|
|
char *upperredirect = NULL;
|
|
struct dentry *this;
|
|
unsigned int i;
|
|
int err;
|
|
struct ovl_lookup_data d = {
|
|
.name = dentry->d_name,
|
|
.is_dir = false,
|
|
.opaque = false,
|
|
.stop = false,
|
|
.last = !poe->numlower,
|
|
.redirect = NULL,
|
|
};
|
|
|
|
if (dentry->d_name.len > ofs->namelen)
|
|
return ERR_PTR(-ENAMETOOLONG);
|
|
|
|
old_cred = ovl_override_creds(dentry->d_sb);
|
|
upperdir = ovl_dentry_upper(dentry->d_parent);
|
|
if (upperdir) {
|
|
err = ovl_lookup_layer(upperdir, &d, &upperdentry);
|
|
if (err)
|
|
goto out;
|
|
|
|
if (upperdentry && unlikely(ovl_dentry_remote(upperdentry))) {
|
|
dput(upperdentry);
|
|
err = -EREMOTE;
|
|
goto out;
|
|
}
|
|
if (upperdentry && !d.is_dir) {
|
|
BUG_ON(!d.stop || d.redirect);
|
|
/*
|
|
* Lookup copy up origin by decoding origin file handle.
|
|
* We may get a disconnected dentry, which is fine,
|
|
* because we only need to hold the origin inode in
|
|
* cache and use its inode number. We may even get a
|
|
* connected dentry, that is not under any of the lower
|
|
* layers root. That is also fine for using it's inode
|
|
* number - it's the same as if we held a reference
|
|
* to a dentry in lower layer that was moved under us.
|
|
*/
|
|
err = ovl_check_origin(upperdentry, roe->lowerstack,
|
|
roe->numlower, &stack, &ctr);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
|
|
if (d.redirect) {
|
|
upperredirect = kstrdup(d.redirect, GFP_KERNEL);
|
|
if (!upperredirect)
|
|
goto out_put_upper;
|
|
if (d.redirect[0] == '/')
|
|
poe = roe;
|
|
}
|
|
upperopaque = d.opaque;
|
|
}
|
|
|
|
if (!d.stop && poe->numlower) {
|
|
err = -ENOMEM;
|
|
stack = kcalloc(ofs->numlower, sizeof(struct path),
|
|
GFP_KERNEL);
|
|
if (!stack)
|
|
goto out_put_upper;
|
|
}
|
|
|
|
for (i = 0; !d.stop && i < poe->numlower; i++) {
|
|
struct path lowerpath = poe->lowerstack[i];
|
|
|
|
d.last = i == poe->numlower - 1;
|
|
err = ovl_lookup_layer(lowerpath.dentry, &d, &this);
|
|
if (err)
|
|
goto out_put;
|
|
|
|
if (!this)
|
|
continue;
|
|
|
|
stack[ctr].dentry = this;
|
|
stack[ctr].mnt = lowerpath.mnt;
|
|
ctr++;
|
|
|
|
if (d.stop)
|
|
break;
|
|
|
|
if (d.redirect && d.redirect[0] == '/' && poe != roe) {
|
|
poe = roe;
|
|
|
|
/* Find the current layer on the root dentry */
|
|
for (i = 0; i < poe->numlower; i++)
|
|
if (poe->lowerstack[i].mnt == lowerpath.mnt)
|
|
break;
|
|
if (WARN_ON(i == poe->numlower))
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Lookup index by lower inode and verify it matches upper inode */
|
|
if (ctr && !d.is_dir && ovl_indexdir(dentry->d_sb)) {
|
|
struct dentry *origin = stack[0].dentry;
|
|
|
|
index = ovl_lookup_index(dentry, upperdentry, origin);
|
|
if (IS_ERR(index)) {
|
|
err = PTR_ERR(index);
|
|
index = NULL;
|
|
goto out_put;
|
|
}
|
|
}
|
|
|
|
oe = ovl_alloc_entry(ctr);
|
|
err = -ENOMEM;
|
|
if (!oe)
|
|
goto out_put;
|
|
|
|
oe->opaque = upperopaque;
|
|
memcpy(oe->lowerstack, stack, sizeof(struct path) * ctr);
|
|
dentry->d_fsdata = oe;
|
|
|
|
if (upperdentry)
|
|
ovl_dentry_set_upper_alias(dentry);
|
|
else if (index)
|
|
upperdentry = dget(index);
|
|
|
|
if (upperdentry || ctr) {
|
|
inode = ovl_get_inode(dentry, upperdentry);
|
|
err = PTR_ERR(inode);
|
|
if (IS_ERR(inode))
|
|
goto out_free_oe;
|
|
|
|
OVL_I(inode)->redirect = upperredirect;
|
|
if (index)
|
|
ovl_set_flag(OVL_INDEX, inode);
|
|
}
|
|
|
|
revert_creds(old_cred);
|
|
dput(index);
|
|
kfree(stack);
|
|
kfree(d.redirect);
|
|
d_add(dentry, inode);
|
|
|
|
return NULL;
|
|
|
|
out_free_oe:
|
|
dentry->d_fsdata = NULL;
|
|
kfree(oe);
|
|
out_put:
|
|
dput(index);
|
|
for (i = 0; i < ctr; i++)
|
|
dput(stack[i].dentry);
|
|
kfree(stack);
|
|
out_put_upper:
|
|
dput(upperdentry);
|
|
kfree(upperredirect);
|
|
out:
|
|
kfree(d.redirect);
|
|
revert_creds(old_cred);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
bool ovl_lower_positive(struct dentry *dentry)
|
|
{
|
|
struct ovl_entry *oe = dentry->d_fsdata;
|
|
struct ovl_entry *poe = dentry->d_parent->d_fsdata;
|
|
const struct qstr *name = &dentry->d_name;
|
|
unsigned int i;
|
|
bool positive = false;
|
|
bool done = false;
|
|
|
|
/*
|
|
* If dentry is negative, then lower is positive iff this is a
|
|
* whiteout.
|
|
*/
|
|
if (!dentry->d_inode)
|
|
return oe->opaque;
|
|
|
|
/* Negative upper -> positive lower */
|
|
if (!ovl_dentry_upper(dentry))
|
|
return true;
|
|
|
|
/* Positive upper -> have to look up lower to see whether it exists */
|
|
for (i = 0; !done && !positive && i < poe->numlower; i++) {
|
|
struct dentry *this;
|
|
struct dentry *lowerdir = poe->lowerstack[i].dentry;
|
|
|
|
this = lookup_one_len_unlocked(name->name, lowerdir,
|
|
name->len);
|
|
if (IS_ERR(this)) {
|
|
switch (PTR_ERR(this)) {
|
|
case -ENOENT:
|
|
case -ENAMETOOLONG:
|
|
break;
|
|
|
|
default:
|
|
/*
|
|
* Assume something is there, we just couldn't
|
|
* access it.
|
|
*/
|
|
positive = true;
|
|
break;
|
|
}
|
|
} else {
|
|
if (this->d_inode) {
|
|
positive = !ovl_is_whiteout(this);
|
|
done = true;
|
|
}
|
|
dput(this);
|
|
}
|
|
}
|
|
|
|
return positive;
|
|
}
|