diff options
Diffstat (limited to 'fs/overlayfs/dir.c')
-rw-r--r-- | fs/overlayfs/dir.c | 113 |
1 files changed, 62 insertions, 51 deletions
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index a2b1d7ce3e1a..ba5ef733951f 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -511,6 +511,7 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir) struct dentry *upper; struct dentry *opaquedir = NULL; int err; + int flags = 0; if (WARN_ON(!workdir)) return -EROFS; @@ -540,46 +541,39 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir) if (err) goto out_dput; - whiteout = ovl_whiteout(workdir, dentry); - err = PTR_ERR(whiteout); - if (IS_ERR(whiteout)) + upper = lookup_one_len(dentry->d_name.name, upperdir, + dentry->d_name.len); + err = PTR_ERR(upper); + if (IS_ERR(upper)) goto out_unlock; - upper = ovl_dentry_upper(dentry); - if (!upper) { - upper = lookup_one_len(dentry->d_name.name, upperdir, - dentry->d_name.len); - err = PTR_ERR(upper); - if (IS_ERR(upper)) - goto kill_whiteout; - - err = ovl_do_rename(wdir, whiteout, udir, upper, 0); - dput(upper); - if (err) - goto kill_whiteout; - } else { - int flags = 0; + err = -ESTALE; + if ((opaquedir && upper != opaquedir) || + (!opaquedir && ovl_dentry_upper(dentry) && + upper != ovl_dentry_upper(dentry))) { + goto out_dput_upper; + } - if (opaquedir) - upper = opaquedir; - err = -ESTALE; - if (upper->d_parent != upperdir) - goto kill_whiteout; + whiteout = ovl_whiteout(workdir, dentry); + err = PTR_ERR(whiteout); + if (IS_ERR(whiteout)) + goto out_dput_upper; - if (is_dir) - flags |= RENAME_EXCHANGE; + if (d_is_dir(upper)) + flags = RENAME_EXCHANGE; - err = ovl_do_rename(wdir, whiteout, udir, upper, flags); - if (err) - goto kill_whiteout; + err = ovl_do_rename(wdir, whiteout, udir, upper, flags); + if (err) + goto kill_whiteout; + if (flags) + ovl_cleanup(wdir, upper); - if (is_dir) - ovl_cleanup(wdir, upper); - } ovl_dentry_version_inc(dentry->d_parent); out_d_drop: d_drop(dentry); dput(whiteout); +out_dput_upper: + dput(upper); out_unlock: unlock_rename(workdir, upperdir); out_dput: @@ -596,21 +590,25 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir) { struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); struct inode *dir = upperdir->d_inode; - struct dentry *upper = ovl_dentry_upper(dentry); + struct dentry *upper; int err; mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); + upper = lookup_one_len(dentry->d_name.name, upperdir, + dentry->d_name.len); + err = PTR_ERR(upper); + if (IS_ERR(upper)) + goto out_unlock; + err = -ESTALE; - if (upper->d_parent == upperdir) { - /* Don't let d_delete() think it can reset d_inode */ - dget(upper); + if (upper == ovl_dentry_upper(dentry)) { if (is_dir) err = vfs_rmdir(dir, upper); else err = vfs_unlink(dir, upper, NULL); - dput(upper); ovl_dentry_version_inc(dentry->d_parent); } + dput(upper); /* * Keeping this dentry hashed would mean having to release @@ -620,6 +618,7 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir) */ if (!err) d_drop(dentry); +out_unlock: mutex_unlock(&dir->i_mutex); return err; @@ -840,29 +839,39 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, trap = lock_rename(new_upperdir, old_upperdir); - olddentry = ovl_dentry_upper(old); - newdentry = ovl_dentry_upper(new); - if (newdentry) { + + olddentry = lookup_one_len(old->d_name.name, old_upperdir, + old->d_name.len); + err = PTR_ERR(olddentry); + if (IS_ERR(olddentry)) + goto out_unlock; + + err = -ESTALE; + if (olddentry != ovl_dentry_upper(old)) + goto out_dput_old; + + newdentry = lookup_one_len(new->d_name.name, new_upperdir, + new->d_name.len); + err = PTR_ERR(newdentry); + if (IS_ERR(newdentry)) + goto out_dput_old; + + err = -ESTALE; + if (ovl_dentry_upper(new)) { if (opaquedir) { - newdentry = opaquedir; - opaquedir = NULL; + if (newdentry != opaquedir) + goto out_dput; } else { - dget(newdentry); + if (newdentry != ovl_dentry_upper(new)) + goto out_dput; } } else { new_create = true; - newdentry = lookup_one_len(new->d_name.name, new_upperdir, - new->d_name.len); - err = PTR_ERR(newdentry); - if (IS_ERR(newdentry)) - goto out_unlock; + if (!d_is_negative(newdentry) && + (!new_opaque || !ovl_is_whiteout(newdentry))) + goto out_dput; } - err = -ESTALE; - if (olddentry->d_parent != old_upperdir) - goto out_dput; - if (newdentry->d_parent != new_upperdir) - goto out_dput; if (olddentry == trap) goto out_dput; if (newdentry == trap) @@ -925,6 +934,8 @@ static int ovl_rename2(struct inode *olddir, struct dentry *old, out_dput: dput(newdentry); +out_dput_old: + dput(olddentry); out_unlock: unlock_rename(new_upperdir, old_upperdir); out_revert_creds: |