This moves various calls to mkdir(1) to very early boot, before any services are running. This has two advantages: 1. These directories are guaranteed to exist. Code can just assume that they are there without checking for them. 2. Malicious code running as an unprivileged user cannot create directories under /tmp before legitimate code has done so. The following directories are created under /tmp: - /tmp/.font-unix (used by obsolete X Font Server) is created with mode 0000. - The directories used by X11 are created with 1700 permissions: - /tmp/.X11-unix (X server) - /tmp/.ICE-unix (Inter-Client Exchange) - /tmp/.XIM-unix (X Input Methods) - $XDG_RUNTIME_DIR (/run/user/0) is created with 0700 permissions, as expected by the XDG specification. The copyright notice for directory creation is not kept because making one directories with well-known names and permissions is not copyrightable and the code has been rewritten. Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com> --- Changes since v6: - Add missing S-o-b - Add comments explaining why each directory needs to be created. - Fix spelling errors in commit messages. Changes since v5: - Remove "directories" service in favor of creating the directories from rc.init. --- img/app/etc/s6-linux-init/scripts/rc.init | 13 +++++++++++++ img/app/etc/s6-rc/wayland-proxy-virtwl/run | 10 ---------- 2 files changed, 13 insertions(+), 10 deletions(-) diff --git a/img/app/etc/s6-linux-init/scripts/rc.init b/img/app/etc/s6-linux-init/scripts/rc.init index c5a59245ff3761e94acb974edde967806fb3b234..7744286d0282bb8e0cc40973c6a6eae4c9401630 100755 --- a/img/app/etc/s6-linux-init/scripts/rc.init +++ b/img/app/etc/s6-linux-init/scripts/rc.init @@ -1,10 +1,23 @@ #!/bin/execlineb -P # SPDX-License-Identifier: EUPL-1.2+ # SPDX-FileCopyrightText: 2020-2022 Alyssa Ross <hi@alyssa.is> +# SPDX-FileCopyrightText: 2025 Demi Marie Obenour <demiobenour@gmail.com> if { s6-rc-init -c /etc/s6-rc /run/service } if { modprobe overlay } if { mount -a --mkdir } +# X Font Server is obsolete +if { mkdir -m 0000 /tmp/.font-unix } + +# /tmp/.X11-unix: X11 server +# /tmp/.ICE-unix: X11 Inter-Client Exchange +# /tmp/.XIM-unix: X11 input methods +# Some documentation states sticky bit is required. +if { mkdir -m 1700 /tmp/.X11-unix /tmp/.ICE-unix /tmp/.XIM-unix } + +# /run/user/0: "$XDG_RUNTIME_DIR" +if { mkdir -m 0700 /run/user/0 } + s6-rc change ok-all diff --git a/img/app/etc/s6-rc/wayland-proxy-virtwl/run b/img/app/etc/s6-rc/wayland-proxy-virtwl/run index 0715d912953c8a1d326059dfd37c29799fcbb053..c1e0e088c789ab8c5fde7e50c9f4b856fff0e477 100755 --- a/img/app/etc/s6-rc/wayland-proxy-virtwl/run +++ b/img/app/etc/s6-rc/wayland-proxy-virtwl/run @@ -1,16 +1,6 @@ #!/bin/execlineb -P # SPDX-License-Identifier: EUPL-1.2+ # SPDX-FileCopyrightText: 2023-2024 Alyssa Ross <hi@alyssa.is> -# -# Directory creation (if it's copyrightable): -# SPDX-License-Identifier: MIT -# SPDX-FileCopyrightText: 2022 Unikie - -foreground { mkdir /tmp/.X11-unix } -foreground { - umask 077 - mkdir /run/user/0 -} s6-ipcserver-socketbinder -B /run/user/0/wayland-0 fdmove -c 3 0 base-commit: 560fd878ba1bbd8df0fe28488e72948f28940948 -- Sincerely, Demi Marie Obenour (she/her/hers)