@@ -8812,6 +8812,714 @@ out:
return fret;
}
+static int nested_userns(void)
+{
+ int fret = -1;
+ int ret;
+ pid_t pid;
+ struct list *it, *next;
+ struct userns_hierarchy hierarchy[] = {
+ { .level = 1, .fd_userns = -EBADF, },
+ { .level = 2, .fd_userns = -EBADF, },
+ { .level = 3, .fd_userns = -EBADF, },
+ { .level = 4, .fd_userns = -EBADF, },
+ /* Dummy entry that marks the end. */
+ { .level = MAX_USERNS_LEVEL, .fd_userns = -EBADF, },
+ };
+ struct mount_attr attr_level1 = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ .userns_fd = -EBADF,
+ };
+ struct mount_attr attr_level2 = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ .userns_fd = -EBADF,
+ };
+ struct mount_attr attr_level3 = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ .userns_fd = -EBADF,
+ };
+ struct mount_attr attr_level4 = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ .userns_fd = -EBADF,
+ };
+ int fd_dir1 = -EBADF,
+ fd_open_tree_level1 = -EBADF,
+ fd_open_tree_level2 = -EBADF,
+ fd_open_tree_level3 = -EBADF,
+ fd_open_tree_level4 = -EBADF;
+ const unsigned int id_file_range = 10000;
+
+ list_init(&hierarchy[0].id_map);
+ list_init(&hierarchy[1].id_map);
+ list_init(&hierarchy[2].id_map);
+ list_init(&hierarchy[3].id_map);
+
+ /*
+ * Give a large map to the outermost user namespace so we can create
+ * comfortable nested maps.
+ */
+ ret = add_map_entry(&hierarchy[0].id_map, 1000000, 0, 1000000000, ID_TYPE_UID);
+ if (ret) {
+ log_stderr("failure: adding uidmap for userns at level 1");
+ goto out;
+ }
+
+ ret = add_map_entry(&hierarchy[0].id_map, 1000000, 0, 1000000000, ID_TYPE_GID);
+ if (ret) {
+ log_stderr("failure: adding gidmap for userns at level 1");
+ goto out;
+ }
+
+ /* This is uid:0->2000000:100000000 in init userns. */
+ ret = add_map_entry(&hierarchy[1].id_map, 1000000, 0, 100000000, ID_TYPE_UID);
+ if (ret) {
+ log_stderr("failure: adding uidmap for userns at level 2");
+ goto out;
+ }
+
+ /* This is gid:0->2000000:100000000 in init userns. */
+ ret = add_map_entry(&hierarchy[1].id_map, 1000000, 0, 100000000, ID_TYPE_GID);
+ if (ret) {
+ log_stderr("failure: adding gidmap for userns at level 2");
+ goto out;
+ }
+
+ /* This is uid:0->3000000:999 in init userns. */
+ ret = add_map_entry(&hierarchy[2].id_map, 1000000, 0, 999, ID_TYPE_UID);
+ if (ret) {
+ log_stderr("failure: adding uidmap for userns at level 3");
+ goto out;
+ }
+
+ /* This is gid:0->3000000:999 in the init userns. */
+ ret = add_map_entry(&hierarchy[2].id_map, 1000000, 0, 999, ID_TYPE_GID);
+ if (ret) {
+ log_stderr("failure: adding gidmap for userns at level 3");
+ goto out;
+ }
+
+ /* id 999 will remain unmapped. */
+
+ /* This is uid:1000->2001000:1 in init userns. */
+ ret = add_map_entry(&hierarchy[2].id_map, 1000, 1000, 1, ID_TYPE_UID);
+ if (ret) {
+ log_stderr("failure: adding uidmap for userns at level 3");
+ goto out;
+ }
+
+ /* This is gid:1000->2001000:1 in init userns. */
+ ret = add_map_entry(&hierarchy[2].id_map, 1000, 1000, 1, ID_TYPE_GID);
+ if (ret) {
+ log_stderr("failure: adding gidmap for userns at level 3");
+ goto out;
+ }
+
+ /* This is uid:1001->3001001:10000 in init userns. */
+ ret = add_map_entry(&hierarchy[2].id_map, 1001001, 1001, 10000000, ID_TYPE_UID);
+ if (ret) {
+ log_stderr("failure: adding uidmap for userns at level 3");
+ goto out;
+ }
+
+ /* This is gid:1001->3001001:10000 in init userns. */
+ ret = add_map_entry(&hierarchy[2].id_map, 1001001, 1001, 10000000, ID_TYPE_GID);
+ if (ret) {
+ log_stderr("failure: adding gidmap for userns at level 3");
+ goto out;
+ }
+
+ /* Don't write a mapping in the 4th userns. */
+ list_empty(&hierarchy[4].id_map);
+
+ /* Create the actual userns hierarchy. */
+ ret = create_userns_hierarchy(hierarchy);
+ if (ret) {
+ log_stderr("failure: create userns hierarchy");
+ goto out;
+ }
+
+ attr_level1.userns_fd = hierarchy[0].fd_userns;
+ attr_level2.userns_fd = hierarchy[1].fd_userns;
+ attr_level3.userns_fd = hierarchy[2].fd_userns;
+ attr_level4.userns_fd = hierarchy[3].fd_userns;
+
+ /*
+ * Create one directory where we create files for each uid/gid within
+ * the first userns.
+ */
+ if (mkdirat(t_dir1_fd, DIR1, 0777)) {
+ log_stderr("failure: mkdirat");
+ goto out;
+ }
+
+ fd_dir1 = openat(t_dir1_fd, DIR1, O_DIRECTORY | O_CLOEXEC);
+ if (fd_dir1 < 0) {
+ log_stderr("failure: openat");
+ goto out;
+ }
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ char file[256];
+
+ snprintf(file, sizeof(file), DIR1 "/" FILE1 "_%u", id);
+
+ if (mknodat(t_dir1_fd, file, S_IFREG | 0644, 0)) {
+ log_stderr("failure: create %s", file);
+ goto out;
+ }
+
+ if (fchownat(t_dir1_fd, file, id, id, AT_SYMLINK_NOFOLLOW)) {
+ log_stderr("failure: fchownat %s", file);
+ goto out;
+ }
+
+ if (!expected_uid_gid(t_dir1_fd, file, 0, id, id)) {
+ log_stderr("failure: check ownership %s", file);
+ goto out;
+ }
+ }
+
+ /* Create detached mounts for all the user namespaces. */
+ fd_open_tree_level1 = sys_open_tree(t_dir1_fd, DIR1,
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ if (fd_open_tree_level1 < 0) {
+ log_stderr("failure: sys_open_tree");
+ goto out;
+ }
+
+ fd_open_tree_level2 = sys_open_tree(t_dir1_fd, DIR1,
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ if (fd_open_tree_level2 < 0) {
+ log_stderr("failure: sys_open_tree");
+ goto out;
+ }
+
+ fd_open_tree_level3 = sys_open_tree(t_dir1_fd, DIR1,
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ if (fd_open_tree_level3 < 0) {
+ log_stderr("failure: sys_open_tree");
+ goto out;
+ }
+
+ fd_open_tree_level4 = sys_open_tree(t_dir1_fd, DIR1,
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ if (fd_open_tree_level4 < 0) {
+ log_stderr("failure: sys_open_tree");
+ goto out;
+ }
+
+ /* Turn detached mounts into detached idmapped mounts. */
+ if (sys_mount_setattr(fd_open_tree_level1, "", AT_EMPTY_PATH,
+ &attr_level1, sizeof(attr_level1))) {
+ log_stderr("failure: sys_mount_setattr");
+ goto out;
+ }
+
+ if (sys_mount_setattr(fd_open_tree_level2, "", AT_EMPTY_PATH,
+ &attr_level2, sizeof(attr_level2))) {
+ log_stderr("failure: sys_mount_setattr");
+ goto out;
+ }
+
+ if (sys_mount_setattr(fd_open_tree_level3, "", AT_EMPTY_PATH,
+ &attr_level3, sizeof(attr_level3))) {
+ log_stderr("failure: sys_mount_setattr");
+ goto out;
+ }
+
+ if (sys_mount_setattr(fd_open_tree_level4, "", AT_EMPTY_PATH,
+ &attr_level4, sizeof(attr_level4))) {
+ log_stderr("failure: sys_mount_setattr");
+ goto out;
+ }
+
+ /* Verify that ownership looks correct for callers in the init userns. */
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ bool bret;
+ unsigned int id_level1, id_level2, id_level3;
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ id_level1 = id + 1000000;
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, id_level1, id_level1)) {
+ log_stderr("failure: check ownership %s", file);
+ goto out;
+ }
+
+ id_level2 = id + 2000000;
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, id_level2, id_level2)) {
+ log_stderr("failure: check ownership %s", file);
+ goto out;
+ }
+
+ if (id == 999) {
+ /* This id is unmapped. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid);
+ } else if (id == 1000) {
+ id_level3 = id + 2000000; /* We punched a hole in the map at 1000. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ } else {
+ id_level3 = id + 3000000; /* Rest is business as usual. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ }
+ if (!bret) {
+ log_stderr("failure: check ownership %s", file);
+ goto out;
+ }
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid)) {
+ log_stderr("failure: check ownership %s", file);
+ goto out;
+ }
+ }
+
+ /* Verify that ownership looks correct for callers in the first userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (!switch_userns(attr_level1.userns_fd, 0, 0, false))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ bool bret;
+ unsigned int id_level1, id_level2, id_level3;
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ id_level1 = id;
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, id_level1, id_level1))
+ die("failure: check ownership %s", file);
+
+ id_level2 = id + 1000000;
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, id_level2, id_level2))
+ die("failure: check ownership %s", file);
+
+ if (id == 999) {
+ /* This id is unmapped. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid);
+ } else if (id == 1000) {
+ id_level3 = id + 1000000; /* We punched a hole in the map at 1000. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ } else {
+ id_level3 = id + 2000000; /* Rest is business as usual. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ }
+ if (!bret)
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ /* Verify that ownership looks correct for callers in the second userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (!switch_userns(attr_level2.userns_fd, 0, 0, false))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ bool bret;
+ unsigned int id_level2, id_level3;
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ id_level2 = id;
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, id_level2, id_level2))
+ die("failure: check ownership %s", file);
+
+ if (id == 999) {
+ /* This id is unmapped. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid);
+ } else if (id == 1000) {
+ id_level3 = id; /* We punched a hole in the map at 1000. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ } else {
+ id_level3 = id + 1000000; /* Rest is business as usual. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ }
+ if (!bret)
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ /* Verify that ownership looks correct for callers in the third userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (!switch_userns(attr_level3.userns_fd, 0, 0, false))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ bool bret;
+ unsigned int id_level2, id_level3;
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (id == 1000) {
+ /*
+ * The idmapping of the third userns has a hole
+ * at uid/gid 1000. That means:
+ * - 1000->userns_0(2000000) // init userns
+ * - 1000->userns_1(2000000) // level 1
+ * - 1000->userns_2(1000000) // level 2
+ * - 1000->userns_3(1000) // level 3 (because level 3 has a hole)
+ */
+ id_level2 = id;
+ bret = expected_uid_gid(fd_open_tree_level2, file, 0, id_level2, id_level2);
+ } else {
+ bret = expected_uid_gid(fd_open_tree_level2, file, 0, t_overflowuid, t_overflowgid);
+ }
+ if (!bret)
+ die("failure: check ownership %s", file);
+
+
+ if (id == 999) {
+ /* This id is unmapped. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid);
+ } else {
+ id_level3 = id; /* Rest is business as usual. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ }
+ if (!bret)
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ /* Verify that ownership looks correct for callers in the fourth userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (setns(attr_level4.userns_fd, CLONE_NEWUSER))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ /* Verify that chown works correctly for callers in the first userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (!switch_userns(attr_level1.userns_fd, 0, 0, false))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ bool bret;
+ unsigned int id_level1, id_level2, id_level3, id_new;
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ id_new = id + 1;
+ if (fchownat(fd_open_tree_level1, file, id_new, id_new, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+
+ id_level1 = id_new;
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, id_level1, id_level1))
+ die("failure: check ownership %s", file);
+
+ id_level2 = id_new + 1000000;
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, id_level2, id_level2))
+ die("failure: check ownership %s", file);
+
+ if (id_new == 999) {
+ /* This id is unmapped. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid);
+ } else if (id_new == 1000) {
+ id_level3 = id_new + 1000000; /* We punched a hole in the map at 1000. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ } else {
+ id_level3 = id_new + 2000000; /* Rest is business as usual. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ }
+ if (!bret)
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ /* Revert ownership. */
+ if (fchownat(fd_open_tree_level1, file, id, id, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ /* Verify that chown works correctly for callers in the second userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (!switch_userns(attr_level2.userns_fd, 0, 0, false))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ bool bret;
+ unsigned int id_level2, id_level3, id_new;
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ id_new = id + 1;
+ if (fchownat(fd_open_tree_level2, file, id_new, id_new, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ id_level2 = id_new;
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, id_level2, id_level2))
+ die("failure: check ownership %s", file);
+
+ if (id_new == 999) {
+ /* This id is unmapped. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid);
+ } else if (id_new == 1000) {
+ id_level3 = id_new; /* We punched a hole in the map at 1000. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ } else {
+ id_level3 = id_new + 1000000; /* Rest is business as usual. */
+ bret = expected_uid_gid(fd_open_tree_level3, file, 0, id_level3, id_level3);
+ }
+ if (!bret)
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ /* Revert ownership. */
+ if (fchownat(fd_open_tree_level2, file, id, id, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ /* Verify that chown works correctly for callers in the third userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (!switch_userns(attr_level3.userns_fd, 0, 0, false))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ unsigned int id_new;
+ char file[256];
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ id_new = id + 1;
+ if (id_new == 999 || id_new == 1000) {
+ /*
+ * We can't change ownership as we can't
+ * chown from or to an unmapped id.
+ */
+ if (!fchownat(fd_open_tree_level3, file, id_new, id_new, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+ } else {
+ if (fchownat(fd_open_tree_level3, file, id_new, id_new, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+ }
+
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ /* There's no id 1000 anymore as we changed ownership for id 1000 to 1001 above. */
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (id_new == 999) {
+ /*
+ * We did not change ownership as we can't
+ * chown to an unmapped id.
+ */
+ if (!expected_uid_gid(fd_open_tree_level3, file, 0, id, id))
+ die("failure: check ownership %s", file);
+ } else if (id_new == 1000) {
+ /*
+ * We did not change ownership as we can't
+ * chown from an unmapped id.
+ */
+ if (!expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+ } else {
+ if (!expected_uid_gid(fd_open_tree_level3, file, 0, id_new, id_new))
+ die("failure: check ownership %s", file);
+ }
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ /* Revert ownership. */
+ if (id_new != 999 && id_new != 1000) {
+ if (fchownat(fd_open_tree_level3, file, id, id, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+ }
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ /* Verify that chown works correctly for callers in the fourth userns. */
+ pid = fork();
+ if (pid < 0) {
+ log_stderr("failure: fork");
+ goto out;
+ }
+ if (pid == 0) {
+ if (setns(attr_level4.userns_fd, CLONE_NEWUSER))
+ die("failure: switch_userns");
+
+ for (unsigned int id = 0; id <= id_file_range; id++) {
+ char file[256];
+ unsigned long id_new;
+
+ snprintf(file, sizeof(file), FILE1 "_%u", id);
+
+ id_new = id + 1;
+ if (!fchownat(fd_open_tree_level4, file, id_new, id_new, AT_SYMLINK_NOFOLLOW))
+ die("failure: fchownat %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level1, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level2, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level3, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ if (!expected_uid_gid(fd_open_tree_level4, file, 0, t_overflowuid, t_overflowgid))
+ die("failure: check ownership %s", file);
+
+ }
+
+ exit(EXIT_SUCCESS);
+ }
+ if (wait_for_pid(pid))
+ goto out;
+
+ fret = 0;
+ log_debug("Ran test");
+
+out:
+ list_for_each_safe(it, &hierarchy[0].id_map, next) {
+ list_del(it);
+ free(it->elem);
+ free(it);
+ }
+
+ list_for_each_safe(it, &hierarchy[1].id_map, next) {
+ list_del(it);
+ free(it->elem);
+ free(it);
+ }
+
+ list_for_each_safe(it, &hierarchy[2].id_map, next) {
+ list_del(it);
+ free(it->elem);
+ free(it);
+ }
+
+ safe_close(hierarchy[0].fd_userns);
+ safe_close(hierarchy[1].fd_userns);
+ safe_close(hierarchy[2].fd_userns);
+ safe_close(fd_dir1);
+ safe_close(fd_open_tree_level1);
+ safe_close(fd_open_tree_level2);
+ safe_close(fd_open_tree_level3);
+ safe_close(fd_open_tree_level4);
+ return fret;
+}
+
static void usage(void)
{
fprintf(stderr, "Description:\n");
@@ -8837,6 +9545,7 @@ static const struct option longopts[] = {
{"help", no_argument, 0, 5},
{"test-core", no_argument, 0, 6},
{"test-fscaps-regression", no_argument, 0, 7},
+ {"test-nested-userns", no_argument, 0, 8},
{NULL, 0, 0, 0},
};
@@ -8899,6 +9608,10 @@ struct t_idmapped_mounts fscaps_in_ancestor_userns[] = {
{ fscaps_idmapped_mounts_in_userns_valid_in_ancestor_userns, "fscaps on idmapped mounts in user namespace writing fscap valid in ancestor userns", },
};
+struct t_idmapped_mounts t_nested_userns[] = {
+ { nested_userns, "test that nested user namespaces behave correctly when attached to idmapped mounts", },
+};
+
static bool run_test(struct t_idmapped_mounts suite[], size_t suite_size)
{
int i;
@@ -8936,7 +9649,8 @@ int main(int argc, char *argv[])
{
int fret, ret;
int index = 0;
- bool supported = false, test_core = false, test_fscaps_regression = false;
+ bool supported = false, test_core = false,
+ test_fscaps_regression = false, test_nested_userns = false;
while ((ret = getopt_long(argc, argv, "", longopts, &index)) != -1) {
switch (ret) {
@@ -8958,6 +9672,9 @@ int main(int argc, char *argv[])
case 7:
test_fscaps_regression = true;
break;
+ case 8:
+ test_nested_userns = true;
+ break;
case 5:
/* fallthrough */
default:
@@ -9035,6 +9752,10 @@ int main(int argc, char *argv[])
ARRAY_SIZE(fscaps_in_ancestor_userns)))
goto out;
+ if (test_nested_userns &&
+ !run_test(t_nested_userns, ARRAY_SIZE(t_nested_userns)))
+ goto out;
+
fret = EXIT_SUCCESS;
out:
@@ -77,6 +77,10 @@ struct userns_hierarchy {
#define list_for_each(__iterator, __list) \
for (__iterator = (__list)->next; __iterator != __list; __iterator = __iterator->next)
+#define list_for_each_safe(__iterator, __list, __next) \
+ for (__iterator = (__list)->next, __next = __iterator->next; \
+ __iterator != __list; __iterator = __next, __next = __next->next)
+
static inline void list_init(struct list *list)
{
list->elem = NULL;
new file mode 100755
@@ -0,0 +1,28 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2021 Christian Brauner. All Rights Reserved.
+#
+# FS QA Test 641
+#
+# Test that idmapped mounts behave correctly with complex user namespaces.
+#
+. ./common/preamble
+_begin_fstest auto quick idmapped mount
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# real QA test starts here
+
+_supported_fs generic
+_require_idmapped_mounts
+_require_test
+
+echo "Silence is golden"
+
+$here/src/idmapped-mounts/idmapped-mounts --test-nested-userns \
+ --device "$TEST_DEV" --mount "$TEST_DIR" --fstype "$FSTYP"
+
+status=$?
+exit
new file mode 100644
@@ -0,0 +1,2 @@
+QA output created by 641
+Silence is golden