Merge pull request #178 from giuseppe/not-override-ino

main: lookup skip ino if there is no origin

.travis.yml

@@ -1,7 +1,7 @@
 services:
   - docker
 env:
-  - GOPATH=$HOME/go GOROOT=/usr/local/go GO=/usr/local/go/bin/go
+  - GOPATH=$HOME/go GOROOT=/usr/local/go GO=/usr/local/go/bin/go PATH=/usr/local/go/bin:$PATH
 language: c
 sudo: required
 dist: xenial
@@ -26,13 +26,13 @@ addons:
 before_install:
   - docker pull fedora &
   - docker build -t alpine-build -f Dockerfile.alpine .
-  - (wget https://dl.google.com/go/go1.10.8.linux-amd64.tar.gz && tar xf go1.10.8.linux-amd64.tar.gz && sudo mv go /usr/local)
+  - (wget https://dl.google.com/go/go1.13.7.linux-amd64.tar.gz && tar xf go1.13.7.linux-amd64.tar.gz && sudo mv go /usr/local)
   - sudo mkdir -p /lower /upper /mnt
   - (cd /; sudo git clone https://github.com/amir73il/unionmount-testsuite.git)
   - (git clone --depth 1 git://github.com/ninja-build/ninja.git && cd ninja && python3.5 ./bootstrap.py && sudo cp ninja /usr/bin)
   - (git clone --depth 1 -b 0.51.1 https://github.com/mesonbuild/meson.git; cd meson; sudo python3.5 ./setup.py install)
   - (git clone --depth 1 https://github.com/sstephenson/bats.git; cd bats; sudo ./install.sh /usr/local)
-  - (go get github.com/containers/storage; cd $GOPATH/src/github.com/containers/storage; sed -i -e 's|^AUTOTAGS.*$|AUTOTAGS := exclude_graphdriver_devicemapper exclude_graphdriver_btrfs|' Makefile; make GO=$GO containers-storage)
+  - ($GO get github.com/containers/storage; cd $GOPATH/src/github.com/containers/storage; sed -i -e 's|^AUTOTAGS.*$|AUTOTAGS := exclude_graphdriver_devicemapper exclude_graphdriver_btrfs|' Makefile; make GO=$GO containers-storage)
   - (wget https://github.com/libfuse/libfuse/releases/download/fuse-3.6.2/fuse-3.6.2.tar.xz; tar xf fuse-3.6.2.tar.xz; cd fuse-3.6.2; mkdir build; cd build; meson .. --prefix /usr && ninja && sudo ninja install)
 script:
   - ./autogen.sh || travis_terminate 1;

main.c

@@ -1,7 +1,7 @@
 /* fuse-overlayfs: Overlay Filesystem in Userspace
 
    Copyright (C) 2018 Giuseppe Scrivano <giuseppe@scrivano.org>
-   Copyright (C) 2018-2019 Red Hat Inc.
+   Copyright (C) 2018-2020 Red Hat Inc.
    Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
 
    This program is free software: you can redistribute it and/or modify
@@ -463,6 +463,22 @@ can_access_xattr (const char *name)
     && !has_prefix (name, PRIVILEGED_XATTR_PREFIX);
 }
 
+static int
+set_fd_origin (int fd, const char *origin)
+{
+  cleanup_close int opq_whiteout_fd = -1;
+  size_t len = strlen (origin) + 1;
+  int ret;
+
+  ret = fsetxattr (fd, ORIGIN_XATTR, origin, len, 0);
+  if (ret < 0)
+    {
+      if (errno == ENOTSUP)
+        return 0;
+    }
+  return ret;
+}
+
 static int
 set_fd_opaque (int fd)
 {
@@ -1153,6 +1169,7 @@ make_ovl_node (struct ovl_data *lo, const char *path, struct ovl_layer *layer, c
   mode_t mode = 0;
   char *new_name;
   struct ovl_node *ret_xchg;
+  bool has_origin = true;
   cleanup_node_init struct ovl_node *ret = NULL;
 
   ret = calloc (1, sizeof (*ret));
@@ -1233,10 +1250,13 @@ make_ovl_node (struct ovl_data *lo, const char *path, struct ovl_layer *layer, c
             {
               if (it->ds->statat (it, npath, &st, AT_SYMLINK_NOFOLLOW, STATX_TYPE|STATX_MODE|STATX_INO) == 0)
                 {
-                  ret->tmp_ino = st.st_ino;
-                  ret->tmp_dev = st.st_dev;
-                  if (mode == 0)
-                    mode = st.st_mode;
+                  if (has_origin)
+                    {
+                      ret->tmp_ino = st.st_ino;
+                      ret->tmp_dev = st.st_dev;
+                      if (mode == 0)
+                        mode = st.st_mode;
+                    }
                   ret->last_layer = it;
                 }
                 goto no_fd;
@@ -1245,10 +1265,13 @@ make_ovl_node (struct ovl_data *lo, const char *path, struct ovl_layer *layer, c
           /* It is an open FD, stat the file and read the origin xattrs.  */
           if (it->ds->fstat (it, fd, npath, STATX_TYPE|STATX_MODE|STATX_INO, &st) == 0)
             {
-              ret->tmp_ino = st.st_ino;
-              ret->tmp_dev = st.st_dev;
-              if (mode == 0)
-                mode = st.st_mode;
+              if (has_origin)
+                {
+                  ret->tmp_ino = st.st_ino;
+                  ret->tmp_dev = st.st_dev;
+                  if (mode == 0)
+                    mode = st.st_mode;
+                }
               ret->last_layer = it;
             }
 
@@ -1292,7 +1315,9 @@ make_ovl_node (struct ovl_data *lo, const char *path, struct ovl_layer *layer, c
 
           /* If an origin is specified, use it for the next layer lookup.  */
           s = safe_read_xattr (&origin, fd, ORIGIN_XATTR, PATH_MAX);
-          if (s > 0)
+          if (s <= 0)
+            has_origin = false;
+          else
             {
               free (npath);
               npath = origin;
@@ -2692,6 +2717,9 @@ copyup (struct ovl_data *lo, struct ovl_node *node)
   if (ret < 0)
     goto exit;
 
+  if (set_fd_origin (dfd, node->path) < 0)
+    goto exit;
+
   /* Finally, move the file to its destination.  */
   ret = renameat (lo->workdir_fd, wd_tmp_file_name, get_upper_layer (lo)->fd, node->path);
   if (ret < 0)

utils.c

@@ -146,7 +146,7 @@ open_fd_or_get_path (struct ovl_layer *l, const char *path, char *out, int *fd,
   out[0] = '\0';
 
   *fd = l->ds->openat (l, path, O_NONBLOCK|O_NOFOLLOW|flags, 0755);
-  if (*fd < 0 && (errno == ELOOP || errno == EISDIR))
+  if (*fd < 0 && (errno == ELOOP || errno == EISDIR || errno == ENXIO))
     {
       strconcat3 (out, PATH_MAX, l->path, "/", path);
       return 0;