diff options
Diffstat (limited to 'fs/overlayfs/namei.c')
| -rw-r--r-- | fs/overlayfs/namei.c | 28 |
1 files changed, 18 insertions, 10 deletions
diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c index a6162c4076db..3fe05fb5d145 100644 --- a/fs/overlayfs/namei.c +++ b/fs/overlayfs/namei.c @@ -150,17 +150,22 @@ invalid: goto out; } -struct dentry *ovl_decode_real_fh(struct ovl_fh *fh, struct vfsmount *mnt, - bool connected) +struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh, + struct vfsmount *mnt, bool connected) { struct dentry *real; int bytes; + if (!capable(CAP_DAC_READ_SEARCH)) + return NULL; + /* * Make sure that the stored uuid matches the uuid of the lower * layer where file handle will be decoded. + * In case of uuid=off option just make sure that stored uuid is null. */ - if (!uuid_equal(&fh->fb.uuid, &mnt->mnt_sb->s_uuid)) + if (ofs->config.uuid ? !uuid_equal(&fh->fb.uuid, &mnt->mnt_sb->s_uuid) : + !uuid_is_null(&fh->fb.uuid)) return NULL; bytes = (fh->fb.len - offsetof(struct ovl_fb, fid)); @@ -354,7 +359,7 @@ int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected, ofs->layers[i].fs->bad_uuid) continue; - origin = ovl_decode_real_fh(fh, ofs->layers[i].mnt, + origin = ovl_decode_real_fh(ofs, fh, ofs->layers[i].mnt, connected); if (origin) break; @@ -450,7 +455,7 @@ int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry, struct ovl_fh *fh; int err; - fh = ovl_encode_real_fh(real, is_upper); + fh = ovl_encode_real_fh(ofs, real, is_upper); err = PTR_ERR(fh); if (IS_ERR(fh)) { fh = NULL; @@ -488,7 +493,7 @@ struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index) if (IS_ERR_OR_NULL(fh)) return ERR_CAST(fh); - upper = ovl_decode_real_fh(fh, ovl_upper_mnt(ofs), true); + upper = ovl_decode_real_fh(ofs, fh, ovl_upper_mnt(ofs), true); kfree(fh); if (IS_ERR_OR_NULL(upper)) @@ -640,12 +645,13 @@ static int ovl_get_index_name_fh(struct ovl_fh *fh, struct qstr *name) * index dir was cleared. Either way, that index cannot be used to indentify * the overlay inode. */ -int ovl_get_index_name(struct dentry *origin, struct qstr *name) +int ovl_get_index_name(struct ovl_fs *ofs, struct dentry *origin, + struct qstr *name) { struct ovl_fh *fh; int err; - fh = ovl_encode_real_fh(origin, false); + fh = ovl_encode_real_fh(ofs, origin, false); if (IS_ERR(fh)) return PTR_ERR(fh); @@ -694,7 +700,7 @@ struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper, bool is_dir = d_is_dir(origin); int err; - err = ovl_get_index_name(origin, &name); + err = ovl_get_index_name(ofs, origin, &name); if (err) return ERR_PTR(err); @@ -805,7 +811,7 @@ static int ovl_fix_origin(struct ovl_fs *ofs, struct dentry *dentry, if (err) return err; - err = ovl_set_origin(dentry, lower, upper); + err = ovl_set_origin(ofs, dentry, lower, upper); if (!err) err = ovl_set_impure(dentry->d_parent, upper->d_parent); @@ -1003,6 +1009,8 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, * Just make sure a corresponding data dentry has been found. */ if (d.metacopy || (uppermetacopy && !ctr)) { + pr_warn_ratelimited("metacopy with no lower data found - abort lookup (%pd2)\n", + dentry); err = -EIO; goto out_put; } else if (!d.is_dir && upperdentry && !ctr && origin_path) { |