diff --git a/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c b/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c index 301fb5c02852..1d0ae785a667 100644 --- a/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c +++ b/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c @@ -149,4 +149,69 @@ TEST_F(set_layers_via_fds, set_layers_via_fds) ASSERT_EQ(fclose(f_mountinfo), 0); } +TEST_F(set_layers_via_fds, set_500_layers_via_fds) +{ + int fd_context, fd_tmpfs, fd_overlay, fd_work, fd_upper, fd_lower; + int layer_fds[500] = { [0 ... 499] = -EBADF }; + + ASSERT_EQ(unshare(CLONE_NEWNS), 0); + ASSERT_EQ(sys_mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL), 0); + + fd_context = sys_fsopen("tmpfs", 0); + ASSERT_GE(fd_context, 0); + + ASSERT_EQ(sys_fsconfig(fd_context, FSCONFIG_CMD_CREATE, NULL, NULL, 0), 0); + fd_tmpfs = sys_fsmount(fd_context, 0, 0); + ASSERT_GE(fd_tmpfs, 0); + ASSERT_EQ(close(fd_context), 0); + + for (int i = 0; i < ARRAY_SIZE(layer_fds); i++) { + char path[100]; + + sprintf(path, "l%d", i); + ASSERT_EQ(mkdirat(fd_tmpfs, path, 0755), 0); + layer_fds[i] = openat(fd_tmpfs, path, O_DIRECTORY); + ASSERT_GE(layer_fds[i], 0); + } + + ASSERT_EQ(mkdirat(fd_tmpfs, "w", 0755), 0); + fd_work = openat(fd_tmpfs, "w", O_DIRECTORY); + ASSERT_GE(fd_work, 0); + + ASSERT_EQ(mkdirat(fd_tmpfs, "u", 0755), 0); + fd_upper = openat(fd_tmpfs, "u", O_DIRECTORY); + ASSERT_GE(fd_upper, 0); + + ASSERT_EQ(mkdirat(fd_tmpfs, "l501", 0755), 0); + fd_lower = openat(fd_tmpfs, "l501", O_DIRECTORY); + ASSERT_GE(fd_lower, 0); + + ASSERT_EQ(sys_move_mount(fd_tmpfs, "", -EBADF, "/tmp", MOVE_MOUNT_F_EMPTY_PATH), 0); + ASSERT_EQ(close(fd_tmpfs), 0); + + fd_context = sys_fsopen("overlay", 0); + ASSERT_GE(fd_context, 0); + + ASSERT_EQ(sys_fsconfig(fd_context, FSCONFIG_SET_FD, "workdir", NULL, fd_work), 0); + ASSERT_EQ(close(fd_work), 0); + + ASSERT_EQ(sys_fsconfig(fd_context, FSCONFIG_SET_FD, "upperdir", NULL, fd_upper), 0); + ASSERT_EQ(close(fd_upper), 0); + + for (int i = 0; i < ARRAY_SIZE(layer_fds); i++) { + ASSERT_EQ(sys_fsconfig(fd_context, FSCONFIG_SET_FD, "lowerdir+", NULL, layer_fds[i]), 0); + ASSERT_EQ(close(layer_fds[i]), 0); + } + + ASSERT_NE(sys_fsconfig(fd_context, FSCONFIG_SET_FD, "lowerdir+", NULL, fd_lower), 0); + ASSERT_EQ(close(fd_lower), 0); + + ASSERT_EQ(sys_fsconfig(fd_context, FSCONFIG_CMD_CREATE, NULL, NULL, 0), 0); + + fd_overlay = sys_fsmount(fd_context, 0, 0); + ASSERT_GE(fd_overlay, 0); + ASSERT_EQ(close(fd_context), 0); + ASSERT_EQ(close(fd_overlay), 0); +} + TEST_HARNESS_MAIN