whiterose

linux unikernel
Log | Files | Refs | README | LICENSE | git clone https://git.ne02ptzero.me/git/whiterose

commit 7260935d71b6d582376543844185add72848dde8
parent 34c7685a177a7bc98066f7e5daa42eef621d0bdb
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu,  1 Nov 2018 14:48:48 -0700

Merge tag 'ovl-update-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs updates from Miklos Szeredi:
 "A mix of fixes and cleanups"

* tag 'ovl-update-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: automatically enable redirect_dir on metacopy=on
  ovl: check whiteout in ovl_create_over_whiteout()
  ovl: using posix_acl_xattr_size() to get size instead of posix_acl_to_xattr()
  ovl: abstract ovl_inode lock with a helper
  ovl: remove the 'locked' argument of ovl_nlink_{start,end}
  ovl: relax requirement for non null uuid of lower fs
  ovl: fold copy-up helpers into callers
  ovl: untangle copy up call chain
  ovl: relax permission checking on underlying layers
  ovl: fix recursive oi->lock in ovl_link()
  vfs: fix FIGETBSZ ioctl on an overlayfs file
  ovl: clean up error handling in ovl_get_tmpfile()
  ovl: fix error handling in ovl_verify_set_fh()

Diffstat:
MDocumentation/filesystems/overlayfs.txt | 6++++++
Mfs/ioctl.c | 3+++
Mfs/overlayfs/copy_up.c | 213+++++++++++++++++++++++++++++++++++++++++++++----------------------------------
Mfs/overlayfs/dir.c | 34+++++++++++++++++++++-------------
Mfs/overlayfs/inode.c | 17+++++++++++++----
Mfs/overlayfs/namei.c | 4+++-
Mfs/overlayfs/overlayfs.h | 14++++++++++++--
Mfs/overlayfs/super.c | 68+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---------
Mfs/overlayfs/util.c | 46+++++++++++++++++++++-------------------------
9 files changed, 260 insertions(+), 145 deletions(-)

diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt @@ -286,6 +286,12 @@ pointed by REDIRECT. This should not be possible on local system as setting "trusted." xattrs will require CAP_SYS_ADMIN. But it should be possible for untrusted layers like from a pen drive. +Note: redirect_dir={off|nofollow|follow(*)} conflicts with metacopy=on, and +results in an error. + +(*) redirect_dir=follow only conflicts with metacopy=on if upperdir=... is +given. + Sharing and copying layers -------------------------- diff --git a/fs/ioctl.c b/fs/ioctl.c @@ -669,6 +669,9 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, return ioctl_fiemap(filp, arg); case FIGETBSZ: + /* anon_bdev filesystems may not have a block size */ + if (!inode->i_sb->s_blocksize) + return -EINVAL; return put_user(inode->i_sb->s_blocksize, argp); case FICLONE: diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c @@ -395,7 +395,6 @@ struct ovl_copy_up_ctx { struct dentry *destdir; struct qstr destname; struct dentry *workdir; - bool tmpfile; bool origin; bool indexed; bool metacopy; @@ -440,63 +439,6 @@ static int ovl_link_up(struct ovl_copy_up_ctx *c) return err; } -static int ovl_install_temp(struct ovl_copy_up_ctx *c, struct dentry *temp, - struct dentry **newdentry) -{ - int err; - struct dentry *upper; - struct inode *udir = d_inode(c->destdir); - - upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len); - if (IS_ERR(upper)) - return PTR_ERR(upper); - - if (c->tmpfile) - err = ovl_do_link(temp, udir, upper); - else - err = ovl_do_rename(d_inode(c->workdir), temp, udir, upper, 0); - - if (!err) - *newdentry = dget(c->tmpfile ? upper : temp); - dput(upper); - - return err; -} - -static struct dentry *ovl_get_tmpfile(struct ovl_copy_up_ctx *c) -{ - int err; - struct dentry *temp; - const struct cred *old_creds = NULL; - struct cred *new_creds = NULL; - struct ovl_cattr cattr = { - /* Can't properly set mode on creation because of the umask */ - .mode = c->stat.mode & S_IFMT, - .rdev = c->stat.rdev, - .link = c->link - }; - - err = security_inode_copy_up(c->dentry, &new_creds); - temp = ERR_PTR(err); - if (err < 0) - goto out; - - if (new_creds) - old_creds = override_creds(new_creds); - - if (c->tmpfile) - temp = ovl_do_tmpfile(c->workdir, c->stat.mode); - else - temp = ovl_create_temp(c->workdir, &cattr); -out: - if (new_creds) { - revert_creds(old_creds); - put_cred(new_creds); - } - - return temp; -} - static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp) { int err; @@ -548,51 +490,148 @@ static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp) return err; } -static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c) +struct ovl_cu_creds { + const struct cred *old; + struct cred *new; +}; + +static int ovl_prep_cu_creds(struct dentry *dentry, struct ovl_cu_creds *cc) +{ + int err; + + cc->old = cc->new = NULL; + err = security_inode_copy_up(dentry, &cc->new); + if (err < 0) + return err; + + if (cc->new) + cc->old = override_creds(cc->new); + + return 0; +} + +static void ovl_revert_cu_creds(struct ovl_cu_creds *cc) +{ + if (cc->new) { + revert_creds(cc->old); + put_cred(cc->new); + } +} + +/* + * Copyup using workdir to prepare temp file. Used when copying up directories, + * special files or when upper fs doesn't support O_TMPFILE. + */ +static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c) { - struct inode *udir = c->destdir->d_inode; struct inode *inode; - struct dentry *newdentry = NULL; - struct dentry *temp; + struct inode *udir = d_inode(c->destdir), *wdir = d_inode(c->workdir); + struct dentry *temp, *upper; + struct ovl_cu_creds cc; int err; + struct ovl_cattr cattr = { + /* Can't properly set mode on creation because of the umask */ + .mode = c->stat.mode & S_IFMT, + .rdev = c->stat.rdev, + .link = c->link + }; - temp = ovl_get_tmpfile(c); + err = ovl_lock_rename_workdir(c->workdir, c->destdir); + if (err) + return err; + + err = ovl_prep_cu_creds(c->dentry, &cc); + if (err) + goto unlock; + + temp = ovl_create_temp(c->workdir, &cattr); + ovl_revert_cu_creds(&cc); + + err = PTR_ERR(temp); if (IS_ERR(temp)) - return PTR_ERR(temp); + goto unlock; err = ovl_copy_up_inode(c, temp); if (err) - goto out; + goto cleanup; if (S_ISDIR(c->stat.mode) && c->indexed) { err = ovl_create_index(c->dentry, c->lowerpath.dentry, temp); if (err) - goto out; + goto cleanup; } - if (c->tmpfile) { - inode_lock_nested(udir, I_MUTEX_PARENT); - err = ovl_install_temp(c, temp, &newdentry); - inode_unlock(udir); - } else { - err = ovl_install_temp(c, temp, &newdentry); - } + upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len); + err = PTR_ERR(upper); + if (IS_ERR(upper)) + goto cleanup; + + err = ovl_do_rename(wdir, temp, udir, upper, 0); + dput(upper); if (err) - goto out; + goto cleanup; if (!c->metacopy) ovl_set_upperdata(d_inode(c->dentry)); inode = d_inode(c->dentry); - ovl_inode_update(inode, newdentry); + ovl_inode_update(inode, temp); if (S_ISDIR(inode->i_mode)) ovl_set_flag(OVL_WHITEOUTS, inode); +unlock: + unlock_rename(c->workdir, c->destdir); -out: - if (err && !c->tmpfile) - ovl_cleanup(d_inode(c->workdir), temp); - dput(temp); return err; +cleanup: + ovl_cleanup(wdir, temp); + dput(temp); + goto unlock; +} + +/* Copyup using O_TMPFILE which does not require cross dir locking */ +static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c) +{ + struct inode *udir = d_inode(c->destdir); + struct dentry *temp, *upper; + struct ovl_cu_creds cc; + int err; + + err = ovl_prep_cu_creds(c->dentry, &cc); + if (err) + return err; + + temp = ovl_do_tmpfile(c->workdir, c->stat.mode); + ovl_revert_cu_creds(&cc); + + if (IS_ERR(temp)) + return PTR_ERR(temp); + + err = ovl_copy_up_inode(c, temp); + if (err) + goto out_dput; + + inode_lock_nested(udir, I_MUTEX_PARENT); + + upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len); + err = PTR_ERR(upper); + if (!IS_ERR(upper)) { + err = ovl_do_link(temp, udir, upper); + dput(upper); + } + inode_unlock(udir); + + if (err) + goto out_dput; + + if (!c->metacopy) + ovl_set_upperdata(d_inode(c->dentry)); + ovl_inode_update(d_inode(c->dentry), temp); + + return 0; + +out_dput: + dput(temp); + return err; } /* @@ -646,18 +685,10 @@ static int ovl_do_copy_up(struct ovl_copy_up_ctx *c) } /* Should we copyup with O_TMPFILE or with workdir? */ - if (S_ISREG(c->stat.mode) && ofs->tmpfile) { - c->tmpfile = true; - err = ovl_copy_up_locked(c); - } else { - err = ovl_lock_rename_workdir(c->workdir, c->destdir); - if (!err) { - err = ovl_copy_up_locked(c); - unlock_rename(c->workdir, c->destdir); - } - } - - + if (S_ISREG(c->stat.mode) && ofs->tmpfile) + err = ovl_copy_up_tmpfile(c); + else + err = ovl_copy_up_workdir(c); if (err) goto out; diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c @@ -414,13 +414,12 @@ static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name, if (!IS_ENABLED(CONFIG_FS_POSIX_ACL) || !acl) return 0; - size = posix_acl_to_xattr(NULL, acl, NULL, 0); + size = posix_acl_xattr_size(acl->a_count); buffer = kmalloc(size, GFP_KERNEL); if (!buffer) return -ENOMEM; - size = posix_acl_to_xattr(&init_user_ns, acl, buffer, size); - err = size; + err = posix_acl_to_xattr(&init_user_ns, acl, buffer, size); if (err < 0) goto out_free; @@ -463,6 +462,10 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode, if (IS_ERR(upper)) goto out_unlock; + err = -ESTALE; + if (d_is_negative(upper) || !IS_WHITEOUT(d_inode(upper))) + goto out_dput; + newdentry = ovl_create_temp(workdir, cattr); err = PTR_ERR(newdentry); if (IS_ERR(newdentry)) @@ -652,7 +655,6 @@ static int ovl_link(struct dentry *old, struct inode *newdir, struct dentry *new) { int err; - bool locked = false; struct inode *inode; err = ovl_want_write(old); @@ -663,13 +665,17 @@ static int ovl_link(struct dentry *old, struct inode *newdir, if (err) goto out_drop_write; + err = ovl_copy_up(new->d_parent); + if (err) + goto out_drop_write; + if (ovl_is_metacopy_dentry(old)) { err = ovl_set_redirect(old, false); if (err) goto out_drop_write; } - err = ovl_nlink_start(old, &locked); + err = ovl_nlink_start(old); if (err) goto out_drop_write; @@ -682,7 +688,7 @@ static int ovl_link(struct dentry *old, struct inode *newdir, if (err) iput(inode); - ovl_nlink_end(old, locked); + ovl_nlink_end(old); out_drop_write: ovl_drop_write(old); out: @@ -807,7 +813,6 @@ static bool ovl_pure_upper(struct dentry *dentry) static int ovl_do_remove(struct dentry *dentry, bool is_dir) { int err; - bool locked = false; const struct cred *old_cred; struct dentry *upperdentry; bool lower_positive = ovl_lower_positive(dentry); @@ -828,7 +833,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir) if (err) goto out_drop_write; - err = ovl_nlink_start(dentry, &locked); + err = ovl_nlink_start(dentry); if (err) goto out_drop_write; @@ -844,7 +849,7 @@ static int ovl_do_remove(struct dentry *dentry, bool is_dir) else drop_nlink(dentry->d_inode); } - ovl_nlink_end(dentry, locked); + ovl_nlink_end(dentry); /* * Copy ctime @@ -1008,7 +1013,6 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, unsigned int flags) { int err; - bool locked = false; struct dentry *old_upperdir; struct dentry *new_upperdir; struct dentry *olddentry; @@ -1017,6 +1021,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, bool old_opaque; bool new_opaque; bool cleanup_whiteout = false; + bool update_nlink = false; bool overwrite = !(flags & RENAME_EXCHANGE); bool is_dir = d_is_dir(old); bool new_is_dir = d_is_dir(new); @@ -1074,10 +1079,12 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, err = ovl_copy_up(new); if (err) goto out_drop_write; - } else { - err = ovl_nlink_start(new, &locked); + } else if (d_inode(new)) { + err = ovl_nlink_start(new); if (err) goto out_drop_write; + + update_nlink = true; } old_cred = ovl_override_creds(old->d_sb); @@ -1206,7 +1213,8 @@ out_unlock: unlock_rename(new_upperdir, old_upperdir); out_revert_creds: revert_creds(old_cred); - ovl_nlink_end(new, locked); + if (update_nlink) + ovl_nlink_end(new); out_drop_write: ovl_drop_write(old); out: diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c @@ -286,13 +286,22 @@ int ovl_permission(struct inode *inode, int mask) if (err) return err; - old_cred = ovl_override_creds(inode->i_sb); - if (!upperinode && - !special_file(realinode->i_mode) && mask & MAY_WRITE) { + /* No need to do any access on underlying for special files */ + if (special_file(realinode->i_mode)) + return 0; + + /* No need to access underlying for execute */ + mask &= ~MAY_EXEC; + if ((mask & (MAY_READ | MAY_WRITE)) == 0) + return 0; + + /* Lower files get copied up, so turn write access into read */ + if (!upperinode && mask & MAY_WRITE) { mask &= ~(MAY_WRITE | MAY_APPEND); - /* Make sure mounter can read file for copy up later */ mask |= MAY_READ; } + + old_cred = ovl_override_creds(inode->i_sb); err = inode_permission(realinode, mask); revert_creds(old_cred); diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c @@ -422,8 +422,10 @@ int ovl_verify_set_fh(struct dentry *dentry, const char *name, fh = ovl_encode_real_fh(real, is_upper); err = PTR_ERR(fh); - if (IS_ERR(fh)) + if (IS_ERR(fh)) { + fh = NULL; goto fail; + } err = ovl_verify_fh(dentry, name, fh); if (set && err == -ENODATA) diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h @@ -271,8 +271,8 @@ bool ovl_test_flag(unsigned long flag, struct inode *inode); bool ovl_inuse_trylock(struct dentry *dentry); void ovl_inuse_unlock(struct dentry *dentry); bool ovl_need_index(struct dentry *dentry); -int ovl_nlink_start(struct dentry *dentry, bool *locked); -void ovl_nlink_end(struct dentry *dentry, bool locked); +int ovl_nlink_start(struct dentry *dentry); +void ovl_nlink_end(struct dentry *dentry); int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir); int ovl_check_metacopy_xattr(struct dentry *dentry); bool ovl_is_metacopy_dentry(struct dentry *dentry); @@ -290,6 +290,16 @@ static inline unsigned int ovl_xino_bits(struct super_block *sb) return ofs->xino_bits; } +static inline int ovl_inode_lock(struct inode *inode) +{ + return mutex_lock_interruptible(&OVL_I(inode)->lock); +} + +static inline void ovl_inode_unlock(struct inode *inode) +{ + mutex_unlock(&OVL_I(inode)->lock); +} + /* namei.c */ int ovl_check_fh_len(struct ovl_fh *fh, int fh_len); diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c @@ -472,6 +472,7 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config) { char *p; int err; + bool metacopy_opt = false, redirect_opt = false; config->redirect_mode = kstrdup(ovl_redirect_mode_def(), GFP_KERNEL); if (!config->redirect_mode) @@ -516,6 +517,7 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config) config->redirect_mode = match_strdup(&args[0]); if (!config->redirect_mode) return -ENOMEM; + redirect_opt = true; break; case OPT_INDEX_ON: @@ -548,6 +550,7 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config) case OPT_METACOPY_ON: config->metacopy = true; + metacopy_opt = true; break; case OPT_METACOPY_OFF: @@ -572,13 +575,32 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config) if (err) return err; - /* metacopy feature with upper requires redirect_dir=on */ - if (config->upperdir && config->metacopy && !config->redirect_dir) { - pr_warn("overlayfs: metadata only copy up requires \"redirect_dir=on\", falling back to metacopy=off.\n"); - config->metacopy = false; - } else if (config->metacopy && !config->redirect_follow) { - pr_warn("overlayfs: metadata only copy up requires \"redirect_dir=follow\" on non-upper mount, falling back to metacopy=off.\n"); - config->metacopy = false; + /* + * This is to make the logic below simpler. It doesn't make any other + * difference, since config->redirect_dir is only used for upper. + */ + if (!config->upperdir && config->redirect_follow) + config->redirect_dir = true; + + /* Resolve metacopy -> redirect_dir dependency */ + if (config->metacopy && !config->redirect_dir) { + if (metacopy_opt && redirect_opt) { + pr_err("overlayfs: conflicting options: metacopy=on,redirect_dir=%s\n", + config->redirect_mode); + return -EINVAL; + } + if (redirect_opt) { + /* + * There was an explicit redirect_dir=... that resulted + * in this conflict. + */ + pr_info("overlayfs: disabling metacopy due to redirect_dir=%s\n", + config->redirect_mode); + config->metacopy = false; + } else { + /* Automatically enable redirect otherwise. */ + config->redirect_follow = config->redirect_dir = true; + } } return 0; @@ -1175,9 +1197,29 @@ out: return err; } +static bool ovl_lower_uuid_ok(struct ovl_fs *ofs, const uuid_t *uuid) +{ + unsigned int i; + + if (!ofs->config.nfs_export && !(ofs->config.index && ofs->upper_mnt)) + return true; + + for (i = 0; i < ofs->numlowerfs; i++) { + /* + * We use uuid to associate an overlay lower file handle with a + * lower layer, so we can accept lower fs with null uuid as long + * as all lower layers with null uuid are on the same fs. + */ + if (uuid_equal(&ofs->lower_fs[i].sb->s_uuid, uuid)) + return false; + } + return true; +} + /* Get a unique fsid for the layer */ -static int ovl_get_fsid(struct ovl_fs *ofs, struct super_block *sb) +static int ovl_get_fsid(struct ovl_fs *ofs, const struct path *path) { + struct super_block *sb = path->mnt->mnt_sb; unsigned int i; dev_t dev; int err; @@ -1191,6 +1233,14 @@ static int ovl_get_fsid(struct ovl_fs *ofs, struct super_block *sb) return i + 1; } + if (!ovl_lower_uuid_ok(ofs, &sb->s_uuid)) { + ofs->config.index = false; + ofs->config.nfs_export = false; + pr_warn("overlayfs: %s uuid detected in lower fs '%pd2', falling back to index=off,nfs_export=off.\n", + uuid_is_null(&sb->s_uuid) ? "null" : "conflicting", + path->dentry); + } + err = get_anon_bdev(&dev); if (err) { pr_err("overlayfs: failed to get anonymous bdev for lowerpath\n"); @@ -1225,7 +1275,7 @@ static int ovl_get_lower_layers(struct ovl_fs *ofs, struct path *stack, struct vfsmount *mnt; int fsid; - err = fsid = ovl_get_fsid(ofs, stack[i].mnt->mnt_sb); + err = fsid = ovl_get_fsid(ofs, &stack[i]); if (err < 0) goto out; diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c @@ -65,8 +65,7 @@ struct super_block *ovl_same_sb(struct super_block *sb) */ int ovl_can_decode_fh(struct super_block *sb) { - if (!sb->s_export_op || !sb->s_export_op->fh_to_dentry || - uuid_is_null(&sb->s_uuid)) + if (!sb->s_export_op || !sb->s_export_op->fh_to_dentry) return 0; return sb->s_export_op->encode_fh ? -1 : FILEID_INO32_GEN; @@ -522,13 +521,13 @@ bool ovl_already_copied_up(struct dentry *dentry, int flags) int ovl_copy_up_start(struct dentry *dentry, int flags) { - struct ovl_inode *oi = OVL_I(d_inode(dentry)); + struct inode *inode = d_inode(dentry); int err; - err = mutex_lock_interruptible(&oi->lock); + err = ovl_inode_lock(inode); if (!err && ovl_already_copied_up_locked(dentry, flags)) { err = 1; /* Already copied up */ - mutex_unlock(&oi->lock); + ovl_inode_unlock(inode); } return err; @@ -536,7 +535,7 @@ int ovl_copy_up_start(struct dentry *dentry, int flags) void ovl_copy_up_end(struct dentry *dentry) { - mutex_unlock(&OVL_I(d_inode(dentry))->lock); + ovl_inode_unlock(d_inode(dentry)); } bool ovl_check_origin_xattr(struct dentry *dentry) @@ -739,14 +738,14 @@ fail: * Operations that change overlay inode and upper inode nlink need to be * synchronized with copy up for persistent nlink accounting. */ -int ovl_nlink_start(struct dentry *dentry, bool *locked) +int ovl_nlink_start(struct dentry *dentry) { - struct ovl_inode *oi = OVL_I(d_inode(dentry)); + struct inode *inode = d_inode(dentry); const struct cred *old_cred; int err; - if (!d_inode(dentry)) - return 0; + if (WARN_ON(!inode)) + return -ENOENT; /* * With inodes index is enabled, we store the union overlay nlink @@ -768,11 +767,11 @@ int ovl_nlink_start(struct dentry *dentry, bool *locked) return err; } - err = mutex_lock_interruptible(&oi->lock); + err = ovl_inode_lock(inode); if (err) return err; - if (d_is_dir(dentry) || !ovl_test_flag(OVL_INDEX, d_inode(dentry))) + if (d_is_dir(dentry) || !ovl_test_flag(OVL_INDEX, inode)) goto out; old_cred = ovl_override_creds(dentry->d_sb); @@ -787,27 +786,24 @@ int ovl_nlink_start(struct dentry *dentry, bool *locked) out: if (err) - mutex_unlock(&oi->lock); - else - *locked = true; + ovl_inode_unlock(inode); return err; } -void ovl_nlink_end(struct dentry *dentry, bool locked) +void ovl_nlink_end(struct dentry *dentry) { - if (locked) { - if (ovl_test_flag(OVL_INDEX, d_inode(dentry)) && - d_inode(dentry)->i_nlink == 0) { - const struct cred *old_cred; + struct inode *inode = d_inode(dentry); - old_cred = ovl_override_creds(dentry->d_sb); - ovl_cleanup_index(dentry); - revert_creds(old_cred); - } + if (ovl_test_flag(OVL_INDEX, inode) && inode->i_nlink == 0) { + const struct cred *old_cred; - mutex_unlock(&OVL_I(d_inode(dentry))->lock); + old_cred = ovl_override_creds(dentry->d_sb); + ovl_cleanup_index(dentry); + revert_creds(old_cred); } + + ovl_inode_unlock(inode); } int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir)