diff options
Diffstat (limited to 'fs/overlayfs')
-rw-r--r-- | fs/overlayfs/namei.c | 57 |
1 files changed, 28 insertions, 29 deletions
diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c index e6868110d9f1..59363c4f6ed4 100644 --- a/fs/overlayfs/namei.c +++ b/fs/overlayfs/namei.c @@ -812,7 +812,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, struct dentry *this; unsigned int i; int err; - bool metacopy = false; + bool uppermetacopy = false; struct ovl_lookup_data d = { .sb = dentry->d_sb, .name = dentry->d_name, @@ -858,7 +858,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, goto out_put_upper; if (d.metacopy) - metacopy = true; + uppermetacopy = true; } if (d.redirect) { @@ -895,6 +895,21 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, if (!this) continue; + if ((uppermetacopy || d.metacopy) && !ofs->config.metacopy) { + err = -EPERM; + pr_warn_ratelimited("refusing to follow metacopy origin for (%pd2)\n", dentry); + goto out_put; + } + + /* + * Do not store intermediate metacopy dentries in chain, + * except top most lower metacopy dentry + */ + if (d.metacopy && ctr) { + dput(this); + continue; + } + /* * If no origin fh is stored in upper of a merge dir, store fh * of lower dir and set upper parent "impure". @@ -929,17 +944,6 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, origin = this; } - if (d.metacopy) - metacopy = true; - /* - * Do not store intermediate metacopy dentries in chain, - * except top most lower metacopy dentry - */ - if (d.metacopy && ctr) { - dput(this); - continue; - } - stack[ctr].dentry = this; stack[ctr].layer = lower.layer; ctr++; @@ -971,22 +975,17 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, } } - if (metacopy) { - /* - * Found a metacopy dentry but did not find corresponding - * data dentry - */ - if (d.metacopy) { - err = -EIO; - goto out_put; - } - - err = -EPERM; - if (!ofs->config.metacopy) { - pr_warn_ratelimited("refusing to follow metacopy origin for (%pd2)\n", - dentry); - goto out_put; - } + /* + * For regular non-metacopy upper dentries, there is no lower + * path based lookup, hence ctr will be zero. If a dentry is found + * using ORIGIN xattr on upper, install it in stack. + * + * For metacopy dentry, path based lookup will find lower dentries. + * Just make sure a corresponding data dentry has been found. + */ + if (d.metacopy || (uppermetacopy && !ctr)) { + err = -EIO; + goto out_put; } else if (!d.is_dir && upperdentry && !ctr && origin_path) { if (WARN_ON(stack != NULL)) { err = -EIO; |