- Spectrum Development - spectrum-os.org

[PATCH] host/rootfs: Sandbox crosvm
by Demi Marie Obenour 09 Dec '25

09 Dec '25

This means that a breach of crosvm is not guaranteed to be fatal. The Wayland socket is still only accessible by root, so crosvm must run as root. The known container escape via /proc/self/exe is blocked by bwrap being on a read-only filesystem. Container escapes via /proc are blocked by remounting /proc read-only. Crosvm does not have CAP_SYS_ADMIN so it cannot change mounts. The two remaining steps are: - Run crosvm as an unprivileged user. - Enable seccomp to block most system calls. The latter should be done from within crosvm itself. Signed-off-by: Demi Marie Obenour <demiobenour(a)gmail.com> --- host/rootfs/default.nix | 6 +++--- .../template/data/service/vhost-user-gpu/run | 17 ++++++++++++++++- 2 files changed, 19 insertions(+), 4 deletions(-) diff --git a/host/rootfs/default.nix b/host/rootfs/default.nix index b441a517f3bbb78f84d8566ca6dfd9181d0302be..81e12b6c2e98ca789d2d14e56dd2b7175296c1e8 100644 --- a/host/rootfs/default.nix +++ b/host/rootfs/default.nix @@ -10,7 +10,7 @@ pkgsMusl.callPackage ( { spectrum-host-tools , lib, stdenvNoCC, nixos, runCommand, writeClosure, erofs-utils, s6-rc -, busybox, cloud-hypervisor, cosmic-files, crosvm, cryptsetup +, bubblewrap, busybox, cloud-hypervisor, cosmic-files, crosvm, cryptsetup , dejavu_fonts, dbus, execline, foot, fuse3, iproute2, inotify-tools , jq, kmod, mdevd, mesa, s6, s6-linux-init, socat, systemd , util-linuxMinimal, virtiofsd, westonLite, xdg-desktop-portal @@ -25,8 +25,8 @@ let trivial; packages = [ - btrfs-progs cloud-hypervisor cosmic-files crosvm cryptsetup dbus - execline fuse3 inotify-tools iproute2 jq kmod mdevd s6 s6-linux-init + bubblewrap btrfs-progs cloud-hypervisor cosmic-files crosvm cryptsetup + dbus execline fuse3 inotify-tools iproute2 jq kmod mdevd s6 s6-linux-init s6-rc socat spectrum-host-tools util-linuxMinimal virtiofsd xdg-desktop-portal-spectrum-host diff --git a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/vhost-user-gpu/run b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/vhost-user-gpu/run index 0b4f6a00bc7aed0e721454d584d3bcd47fb18e2a..4838199a859cfadb45c23fb314f4651c6a6b3041 100755 --- a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/vhost-user-gpu/run +++ b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/vhost-user-gpu/run @@ -1,10 +1,25 @@ #!/bin/execlineb -P # SPDX-License-Identifier: EUPL-1.2+ # SPDX-FileCopyrightText: 2025 Alyssa Ross <hi(a)alyssa.is> +# SPDX-FileCopyrightText: 2025 Demi Marie Obenour <demiobenour(a)gmail.com> s6-ipcserver -1a 0700 -C 1 -b 1 env/crosvm.sock -crosvm --no-syslog device gpu +bwrap + --unshare-all + --unshare-user + --bind /run/user/0/wayland-1 /run/user/0/wayland-1 + --ro-bind /usr /usr + --ro-bind /lib /lib + --tmpfs /tmp + --dev /dev + --tmpfs /dev/shm + --ro-bind /nix /nix + --disable-userns + --proc /proc + --remount-ro /proc + -- + crosvm --no-syslog device gpu --fd 0 --wayland-sock /run/user/0/wayland-1 --params "{\"context-types\":\"cross-domain\"}" --- base-commit: 965f5706764edb1b4fea147683b5ab803dd6df5e change-id: 20251129-sandbox-5a42a6a41b59 -- Sincerely, Demi Marie Obenour (she/her/hers)

4 36

[PATCH v2 1/3] tools/router: use socket activation
by Alyssa Ross 09 Dec '25

09 Dec '25

This means we can use readiness notification to wait until the sockets are created without having to add special functionality for that to the router program, and also means we can do extra system-specific setup to the sockets, like changing their owners, outside of the router. Since the socket paths were the only arguments taken by the router, this also lets us drop the clap dependency entirely. Signed-off-by: Alyssa Ross <hi(a)alyssa.is> Message-ID: <20251209003813.553461-1-hi(a)alyssa.is> --- v2: stop passing obsolete arguments to router v1: https://spectrum-os.org/lists/archives/spectrum-devel/20251209003813.553461… host/rootfs/file-list.mk | 1 + .../service/spectrum-router/notification-fd | 1 + .../spectrum-router/notification-fd.license | 2 + .../template/data/service/spectrum-router/run | 21 ++- tools/router/Cargo.lock | 148 ++++++++++++------ tools/router/Cargo.toml | 2 +- tools/router/src/main.rs | 37 ++--- 7 files changed, 138 insertions(+), 74 deletions(-) create mode 100644 host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd create mode 100644 host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd.license diff --git a/host/rootfs/file-list.mk b/host/rootfs/file-list.mk index df22bce8..5a043b7b 100644 --- a/host/rootfs/file-list.mk +++ b/host/rootfs/file-list.mk @@ -28,6 +28,7 @@ FILES = \ image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/dbus/notification-fd \ image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/dbus/run \ image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/down \ + image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd \ image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/run \ image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/vhost-user-fs/notification-fd \ image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/vhost-user-fs/run \ diff --git a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd new file mode 100644 index 00000000..7ed6ff82 --- /dev/null +++ b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd @@ -0,0 +1 @@ +5 diff --git a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd.license b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd.license new file mode 100644 index 00000000..0d3d47ca --- /dev/null +++ b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/notification-fd.license @@ -0,0 +1,2 @@ +SPDX-License-Identifier: CC0-1.0 +SPDX-FileCopyrightText: 2025 Alyssa Ross <hi(a)alyssa.is> diff --git a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/run b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/run index 3ba35def..dc1ef900 100755 --- a/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/run +++ b/host/rootfs/image/etc/s6-linux-init/run-image/service/vm-services/template/data/service/spectrum-router/run @@ -1,14 +1,30 @@ #!/bin/execlineb -P # SPDX-License-Identifier: EUPL-1.2+ # SPDX-FileCopyrightText: 2025 Yureka Lilian <yureka(a)cyberchaos.dev> +# SPDX-FileCopyrightText: 2025 Alyssa Ross <hi(a)alyssa.is> importas -i VM VM +s6-ipcserver-socketbinder -a 0770 /run/vm/by-id/${VM}/router-driver.sock +fdmove -c 3 0 + +s6-ipcserver-socketbinder -a 0770 /run/vm/by-id/${VM}/router-app.sock +fdmove -c 4 0 + +# Notify readiness. +if { + fdmove -c 5 1 + echo +} + +redirfd -r 0 /dev/null + bwrap --unshare-all --unshare-user --dev-bind / / --setenv RUST_LOG spectrum-router=debug,info + --setenv LISTEN_FDS 2 --tmpfs /tmp --dev /dev --tmpfs /dev/shm @@ -19,6 +35,7 @@ bwrap --ro-bind /lib /lib --bind /run/vm/by-id/${VM} /run/vm/by-id/${VM} -- + +getpid LISTEN_PID + spectrum-router - --app-listen-path /run/vm/by-id/${VM}/router-app.sock - --driver-listen-path /run/vm/by-id/${VM}/router-driver.sock diff --git a/tools/router/Cargo.lock b/tools/router/Cargo.lock index 60d7657b..d0d105aa 100644 --- a/tools/router/Cargo.lock +++ b/tools/router/Cargo.lock @@ -113,6 +113,12 @@ dependencies = [ "wyz", ] +[[package]] +name = "bumpalo" +version = "3.19.0" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "46c5e41b57b8bba42a04676d81cb89e9ee8e859a1a66f80a5a72e1cb76b34d43" + [[package]] name = "bytes" version = "1.11.0" @@ -120,44 +126,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "b35204fbdc0b3f4446b89fc1ac2cf84a8a68971995d0bf2e925ec7cd960f9cb3" [[package]] -name = "clap" -version = "4.5.53" +name = "cfg-if" +version = "1.0.4" source = "registry+https://github.com/rust-lang/crates.io-index" -checksum = "c9e340e012a1bf4935f5282ed1436d1489548e8f72308207ea5df0e23d2d03f8" -dependencies = [ - "clap_builder", - "clap_derive", -] - -[[package]] -name = "clap_builder" -version = "4.5.53" -source = "registry+https://github.com/rust-lang/crates.io-index" -checksum = "d76b5d13eaa18c901fd2f7fca939fefe3a0727a953561fefdf3b2922b8569d00" -dependencies = [ - "anstream", - "anstyle", - "clap_lex", - "strsim", -] - -[[package]] -name = "clap_derive" -version = "4.5.49" -source = "registry+https://github.com/rust-lang/crates.io-index" -checksum = "2a0b5487afeab2deb2ff4e03a807ad1a03ac532ff5a2cee5d86884440c7f7671" -dependencies = [ - "heck", - "proc-macro2", - "quote", - "syn", -] - -[[package]] -name = "clap_lex" -version = "0.7.6" -source = "registry+https://github.com/rust-lang/crates.io-index" -checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d" +checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801" [[package]] name = "colorchoice" @@ -263,12 +235,6 @@ dependencies = [ "slab", ] -[[package]] -name = "heck" -version = "0.5.0" -source = "registry+https://github.com/rust-lang/crates.io-index" -checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea" - [[package]] name = "is_terminal_polyfill" version = "1.70.2" @@ -299,12 +265,33 @@ dependencies = [ "syn", ] +[[package]] +name = "js-sys" +version = "0.3.83" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "464a3709c7f55f1f721e5389aa6ea4e3bc6aba669353300af094b29ffbdde1d8" +dependencies = [ + "once_cell", + "wasm-bindgen", +] + [[package]] name = "libc" version = "0.2.177" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "2874a2af47a2325c2001a6e6fad9b16a53b802102b528163885171cf92b15976" +[[package]] +name = "listenfd" +version = "1.0.2" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "b87bc54a4629b4294d0b3ef041b64c40c611097a677d9dc07b2c67739fe39dba" +dependencies = [ + "libc", + "uuid", + "winapi", +] + [[package]] name = "log" version = "0.4.28" @@ -328,6 +315,12 @@ dependencies = [ "windows-sys 0.61.2", ] +[[package]] +name = "once_cell" +version = "1.21.3" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d" + [[package]] name = "once_cell_polyfill" version = "1.70.2" @@ -420,6 +413,12 @@ version = "0.8.8" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "7a2d987857b319362043e95f5353c0535c1f58eec5336fdfcf626430af7def58" +[[package]] +name = "rustversion" +version = "1.0.22" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "b39cdef0fa800fc44525c84ccb54a029961a8215f9619753635a9c0d2538d46d" + [[package]] name = "serde_core" version = "1.0.228" @@ -462,9 +461,9 @@ version = "0.1.0" dependencies = [ "anyhow", "arrayvec", - "clap", "env_logger", "futures-util", + "listenfd", "log", "tokio", "tokio-stream", @@ -474,12 +473,6 @@ dependencies = [ "zerocopy", ] -[[package]] -name = "strsim" -version = "0.11.1" -source = "registry+https://github.com/rust-lang/crates.io-index" -checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f" - [[package]] name = "syn" version = "2.0.111" @@ -608,6 +601,16 @@ version = "0.2.2" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821" +[[package]] +name = "uuid" +version = "1.19.0" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "e2e054861b4bd027cd373e18e8d8d8e6548085000e41290d95ce0c373a654b4a" +dependencies = [ + "js-sys", + "wasm-bindgen", +] + [[package]] name = "vhost-device-net" version = "0.1.1" @@ -666,6 +669,51 @@ version = "0.11.1+wasi-snapshot-preview1" source = "registry+https://github.com/rust-lang/crates.io-index" checksum = "ccf3ec651a847eb01de73ccad15eb7d99f80485de043efb2f370cd654f4ea44b" +[[package]] +name = "wasm-bindgen" +version = "0.2.106" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "0d759f433fa64a2d763d1340820e46e111a7a5ab75f993d1852d70b03dbb80fd" +dependencies = [ + "cfg-if", + "once_cell", + "rustversion", + "wasm-bindgen-macro", + "wasm-bindgen-shared", +] + +[[package]] +name = "wasm-bindgen-macro" +version = "0.2.106" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "48cb0d2638f8baedbc542ed444afc0644a29166f1595371af4fecf8ce1e7eeb3" +dependencies = [ + "quote", + "wasm-bindgen-macro-support", +] + +[[package]] +name = "wasm-bindgen-macro-support" +version = "0.2.106" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "cefb59d5cd5f92d9dcf80e4683949f15ca4b511f4ac0a6e14d4e1ac60c6ecd40" +dependencies = [ + "bumpalo", + "proc-macro2", + "quote", + "syn", + "wasm-bindgen-shared", +] + +[[package]] +name = "wasm-bindgen-shared" +version = "0.2.106" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "cbc538057e648b67f72a982e708d485b2efa771e1ac05fec311f9f63e5800db4" +dependencies = [ + "unicode-ident", +] + [[package]] name = "winapi" version = "0.3.9" diff --git a/tools/router/Cargo.toml b/tools/router/Cargo.toml index 0b969113..cfdf3527 100644 --- a/tools/router/Cargo.toml +++ b/tools/router/Cargo.toml @@ -8,7 +8,6 @@ edition = "2024" [dependencies] anyhow = "1.0.100" -clap = { version = "4.5.45", features = ["derive"] } env_logger = "0.11.8" log = { version = "0.4.27", features = ["release_max_level_debug"] } vhost-device-net = "0.1.0" @@ -19,3 +18,4 @@ tokio-stream = "0.1.17" arrayvec = "0.7.6" vm-memory = "0.16" tokio-util = "0.7.17" +listenfd = "1.0.2" diff --git a/tools/router/src/main.rs b/tools/router/src/main.rs index e3aca65a..a96d5114 100644 --- a/tools/router/src/main.rs +++ b/tools/router/src/main.rs @@ -1,47 +1,42 @@ // SPDX-License-Identifier: EUPL-1.2+ // SPDX-FileCopyrightText: 2025 Yureka Lilian <yureka(a)cyberchaos.dev> +// SPDX-FileCopyrightText: 2025 Alyssa Ross <hi(a)alyssa.is> pub(crate) mod packet; pub(crate) mod protocol; mod router; mod upstream; -use std::path::PathBuf; - use packet::*; use router::{InterfaceId, Router}; use upstream::Upstream; -use clap::Parser; +use anyhow::anyhow; use futures_util::{SinkExt, TryStreamExt}; +use listenfd::ListenFd; use log::{error, info}; use tokio::net::UnixListener; use vhost_device_net::{IncomingPacket, VhostDeviceNet}; use vm_memory::GuestMemoryMmap; -#[derive(Parser, Debug)] -#[command()] //version = None, about = None, long_about = None)] -struct Args { - #[arg(long)] - driver_listen_path: PathBuf, - #[arg(long)] - app_listen_path: PathBuf, -} - fn main() -> anyhow::Result<()> { env_logger::init(); - let args = Args::parse(); - for path in [&args.driver_listen_path, &args.app_listen_path] { - let _ = std::fs::remove_file(path); - } - - run_router(args) + run_router() } #[tokio::main(flavor = "current_thread")] -async fn run_router(args: Args) -> anyhow::Result<()> { - let app_listener = UnixListener::bind(&args.app_listen_path)?; - let driver_listener = UnixListener::bind(&args.driver_listen_path)?; +async fn run_router() -> anyhow::Result<()> { + let mut listenfd = ListenFd::from_env(); + + let Some(driver_listener) = listenfd.take_unix_listener(0)? else { + return Err(anyhow!("not activated with driver socket")); + }; + let Some(app_listener) = listenfd.take_unix_listener(1)? else { + return Err(anyhow!("not activated with app socket")); + }; + + let driver_listener = UnixListener::from_std(driver_listener)?; + let app_listener = UnixListener::from_std(app_listener)?; let mut router = Router::<GuestMemoryMmap>::new(InterfaceId::Upstream); -- 2.51.0

2 3

[PATCH 1/5] host/rootfs: make passwd and group links into /run
by Alyssa Ross 09 Dec '25

09 Dec '25

This will allow us to give shadow's useradd /run as a prefix, and have it be able to add users at runtime. Signed-off-by: Alyssa Ross <hi(a)alyssa.is> --- host/rootfs/file-list.mk | 6 ++++-- host/rootfs/image/etc/group | 16 +--------------- host/rootfs/image/etc/passwd | 2 +- .../etc/{ => s6-linux-init/run-image/etc}/group | 0 .../run-image/etc}/group.license | 0 .../etc/{ => s6-linux-init/run-image/etc}/passwd | 0 .../run-image/etc}/passwd.license | 0 7 files changed, 6 insertions(+), 18 deletions(-) mode change 100644 => 120000 host/rootfs/image/etc/group mode change 100644 => 120000 host/rootfs/image/etc/passwd copy host/rootfs/image/etc/{ => s6-linux-init/run-image/etc}/group (100%) rename host/rootfs/image/etc/{ => s6-linux-init/run-image/etc}/group.license (100%) copy host/rootfs/image/etc/{ => s6-linux-init/run-image/etc}/passwd (100%) rename host/rootfs/image/etc/{ => s6-linux-init/run-image/etc}/passwd.license (100%) diff --git a/host/rootfs/file-list.mk b/host/rootfs/file-list.mk index df22bce..6ab78e6 100644 --- a/host/rootfs/file-list.mk +++ b/host/rootfs/file-list.mk @@ -4,13 +4,13 @@ FILES = \ image/etc/fonts/fonts.conf \ image/etc/fstab \ - image/etc/group \ image/etc/init \ image/etc/login \ image/etc/parse-devname \ - image/etc/passwd \ image/etc/s6-linux-init/env/WAYLAND_DISPLAY \ image/etc/s6-linux-init/env/XDG_RUNTIME_DIR \ + image/etc/s6-linux-init/run-image/etc/group \ + image/etc/s6-linux-init/run-image/etc/passwd \ image/etc/s6-linux-init/run-image/service/getty-tty1/run \ image/etc/s6-linux-init/run-image/service/getty-tty2/run \ image/etc/s6-linux-init/run-image/service/getty-tty3/run \ @@ -68,6 +68,8 @@ FILES = \ LINKS = \ image/bin \ + image/etc/group \ + image/etc/passwd \ image/etc/s6-linux-init/run-image/opengl-driver \ image/etc/s6-linux-init/run-image/service/vmm/template/run \ image/lib \ diff --git a/host/rootfs/image/etc/group b/host/rootfs/image/etc/group deleted file mode 100644 index e3ade46..0000000 --- a/host/rootfs/image/etc/group +++ /dev/null @@ -1,15 +0,0 @@ -root:x:0:root -clock:x:1: -dialout:x:2: -kmem:x:3: -input:x:4: -tty:x:5: -video:x:6: -render:x:7: -sgx:x:8: -audio:x:9: -lp:x:10: -disk:x:11: -cdrom:x:12: -tape:x:13: -kvm:x:14: diff --git a/host/rootfs/image/etc/group b/host/rootfs/image/etc/group new file mode 120000 index 0000000..a9b248e --- /dev/null +++ b/host/rootfs/image/etc/group @@ -0,0 +1 @@ +/run/etc/group \ No newline at end of file diff --git a/host/rootfs/image/etc/passwd b/host/rootfs/image/etc/passwd deleted file mode 100644 index 29f3b25..0000000 --- a/host/rootfs/image/etc/passwd +++ /dev/null @@ -1 +0,0 @@ -root:x:0:0:System administrator:/:/bin/sh diff --git a/host/rootfs/image/etc/passwd b/host/rootfs/image/etc/passwd new file mode 120000 index 0000000..889bb76 --- /dev/null +++ b/host/rootfs/image/etc/passwd @@ -0,0 +1 @@ +/run/etc/passwd \ No newline at end of file diff --git a/host/rootfs/image/etc/group b/host/rootfs/image/etc/s6-linux-init/run-image/etc/group similarity index 100% copy from host/rootfs/image/etc/group copy to host/rootfs/image/etc/s6-linux-init/run-image/etc/group diff --git a/host/rootfs/image/etc/group.license b/host/rootfs/image/etc/s6-linux-init/run-image/etc/group.license similarity index 100% rename from host/rootfs/image/etc/group.license rename to host/rootfs/image/etc/s6-linux-init/run-image/etc/group.license diff --git a/host/rootfs/image/etc/passwd b/host/rootfs/image/etc/s6-linux-init/run-image/etc/passwd similarity index 100% copy from host/rootfs/image/etc/passwd copy to host/rootfs/image/etc/s6-linux-init/run-image/etc/passwd diff --git a/host/rootfs/image/etc/passwd.license b/host/rootfs/image/etc/s6-linux-init/run-image/etc/passwd.license similarity index 100% rename from host/rootfs/image/etc/passwd.license rename to host/rootfs/image/etc/s6-linux-init/run-image/etc/passwd.license base-commit: d0efa283216ebc503b4b715c051518ae7dbd8409 -- 2.51.0

2 14

[PATCH] host/rootfs: Sandbox Cloud Hypervisor
by Demi Marie Obenour 09 Dec '25

09 Dec '25

It only needs access to a small number of resources. Unfortunately, it needs access to /dev/vfio right now. This should be fixed by using file descriptor passing instead. Also, Cloud Hypervisor should not run as root. Cloud Hypervisor needs to be able to lock memory. Running in a user namespace prevents it from using CAP_IPC_LOCK. Therefore, it is necessary to increase RLIMIT_MLOCK before running Cloud Hypervisor. Signed-off-by: Demi Marie Obenour <demiobenour(a)gmail.com> --- host/rootfs/image/usr/bin/run-vmm | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) diff --git a/host/rootfs/image/usr/bin/run-vmm b/host/rootfs/image/usr/bin/run-vmm index ba8b59c2677408acdd01c2eda3cf2dd60992d881..24c3d607bfcf6fea6196b61d2941141486d33fd6 100755 --- a/host/rootfs/image/usr/bin/run-vmm +++ b/host/rootfs/image/usr/bin/run-vmm @@ -52,5 +52,36 @@ unexport ! fdmove -c 3 0 redirfd -r 0 /dev/null +s6-softlimit -H -l 18446744073709551615 if { udevadm wait /dev/kvm } -cloud-hypervisor --api-socket fd=3 +bwrap + --unshare-all + --unshare-user + --dev /dev + --dev-bind /dev/kvm /dev/kvm + --dev-bind /dev/vfio /dev/vfio + --tmpfs /dev/shm + --tmpfs /tmp + --tmpfs /var/tmp + --ro-bind /etc /etc + --ro-bind /lib /lib + --ro-bind /nix /nix + --ro-bind /usr /usr + --ro-bind /sys /sys + --bind /run /run + --proc /proc + --ro-bind /proc/sys /proc/sys + --tmpfs /proc/scsi + --remount-ro /proc/scsi + --tmpfs /proc/acpi + --remount-ro /proc/acpi + --tmpfs /proc/fs + --remount-ro /proc/fs + --tmpfs /proc/irq + --remount-ro /proc/irq + --ro-bind /dev/null /proc/timer_list + --ro-bind /dev/null /proc/kcore + --ro-bind /dev/null /proc/kallsyms + --ro-bind /dev/null /proc/sysrq-trigger + -- + cloud-hypervisor --api-socket fd=3 --- base-commit: 92e219e7c08c479d216a46d2736ea9d229ff034d change-id: 20251206-b4-sandbox-9be7e5ed9926 -- Sincerely, Demi Marie Obenour (she/her/hers)

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[PATCH v2 1/2] vm/app/systemd-sysupdate: fix mounting overlay
by Alyssa Ross 09 Dec '25

09 Dec '25

This assumed it would be run as root, so has been broken since we stopped running application scripts as root inside img/app VMs. Reported-by: Johannes Süllner <johannes.suellner(a)mailbox.org> Link: https://matrix.to/#/!xSysqhzbOZImdvGpix:fairydust.space/$9psDI3BIP00EIzW-qO… Fixes: 8bfcbf9 ("img/app: run applications as non-root") Signed-off-by: Alyssa Ross <hi(a)alyssa.is> --- v2: remove redundant -U flag v1: https://spectrum-os.org/lists/archives/spectrum-devel/20251208154738.300709… vm/app/systemd-sysupdate/download-update | 1 + 1 file changed, 1 insertion(+) diff --git a/vm/app/systemd-sysupdate/download-update b/vm/app/systemd-sysupdate/download-update index eada41c..f8f5aed 100755 --- a/vm/app/systemd-sysupdate/download-update +++ b/vm/app/systemd-sysupdate/download-update @@ -3,6 +3,7 @@ # SPDX-FileCopyrightText: 2025 Demi Marie Obenour <demiobenour(a)gmail.com> export LC_ALL C export LANGUAGE C +unshare -mr if { mount -toverlay -olowerdir=/run/virtiofs/virtiofs0/etc:/etc -- overlay /etc } backtick tmpdir { mktemp -d /tmp/sysupdate-XXXXXX } # Not a useless use of cat: if there are NUL bytes in the URL base-commit: 5104fa720ce8b00612c5487fc47124fbf99e58c6 -- 2.51.0

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[PATCH] img/app: fix running AppImages
by Alyssa Ross 09 Dec '25

09 Dec '25

The non-root user that applications run as can't mount FUSE filesystems. I don't want to introduce setuid or an IPC service just for running AppImages, although we could revisit if we find that applications themselves rely on being able to mount FUSE filesystems. For now, it'll be more efficient to use the in-kernel squashfs implementation anyway. We do need to set a few environment variables normally set by the AppImage runtime, but as far as I can tell it doesn't do much more than this that applications could rely on. This only works for type 2 AppImages, but I expect that's just about every AppImage nowadays, and if turns out not to be it shouldn't be too hard to support type 1. Fixes: 8bfcbf9 ("img/app: run applications as non-root") Signed-off-by: Alyssa Ross <hi(a)alyssa.is> --- img/app/Makefile | 2 +- img/app/image/etc/s6-rc/app/run | 11 +++++++++-- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/img/app/Makefile b/img/app/Makefile index ddfc8ef..7354f89 100644 --- a/img/app/Makefile +++ b/img/app/Makefile @@ -30,7 +30,7 @@ $(imgdir)/appvm/blk/root.img: ../../scripts/make-gpt.sh ../../scripts/sfdisk-fie build/rootfs.erofs:root:5460386f-2203-4911-8694-91400125c604:root mv $@.tmp $@ -DIRS = dev home/user run proc sys tmp \ +DIRS = dev home/user run mnt proc sys tmp \ etc/s6-linux-init/run-image/pipewire \ etc/s6-linux-init/run-image/service \ etc/s6-linux-init/run-image/user \ diff --git a/img/app/image/etc/s6-rc/app/run b/img/app/image/etc/s6-rc/app/run index e05d4fe..e691a63 100755 --- a/img/app/image/etc/s6-rc/app/run +++ b/img/app/image/etc/s6-rc/app/run @@ -14,10 +14,17 @@ foreground { withstdinas -E type case $type { appimage { - if { modprobe fuse } + if { modprobe loop } + if { + backtick -E offset { /run/virtiofs/virtiofs0/config/run --appimage-offset } + mount -o offset=${offset} /run/virtiofs/virtiofs0/config/run /mnt + } s6-setuidgid user + export APPIMAGE /run/virtiofs/virtiofs0/config/run + export APPDIR /mnt + export ARGV0 /mnt/AppRun export LD_LIBRARY_PATH /lib64 - /run/virtiofs/virtiofs0/config/run + /mnt/AppRun } flatpak { s6-envdir -fnL /run/virtiofs/virtiofs0/config/params base-commit: 5104fa720ce8b00612c5487fc47124fbf99e58c6 -- 2.51.0

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[PATCH] img/app: fix X11
by Alyssa Ross 09 Dec '25

09 Dec '25

Xwayland only accepts connections from the user it's running as. It is started by wayland-proxy-virtwl, which does not allow passing extra options, so we can't change its authentication method. Therefore, the only way for X11 to work with the current software is to run wayland-proxy-virtwl as the same user as the application. I expect that in the near future, we will use xwayland-satellite instead of the built-in Xwayland translation in wayland-proxy-virtwl. When that happens, we can run the stub compositor as its own user again. Fixes: cb27e3a ("img/app: wayland-proxy-virtwl: run as non-root") Signed-off-by: Alyssa Ross <hi(a)alyssa.is> --- img/app/image/etc/group | 1 - img/app/image/etc/mdev.conf | 2 +- img/app/image/etc/passwd | 1 - img/app/image/etc/s6-rc/wayland-proxy-virtwl/run | 2 +- 4 files changed, 2 insertions(+), 4 deletions(-) diff --git a/img/app/image/etc/group b/img/app/image/etc/group index b2c3a2e..e84da60 100644 --- a/img/app/image/etc/group +++ b/img/app/image/etc/group @@ -1,4 +1,3 @@ -wayland:x:1:wayland wireplumber:x:2:wireplumber pipewire:x:3:pipewire user:x:1000:user diff --git a/img/app/image/etc/mdev.conf b/img/app/image/etc/mdev.conf index d4cd825..33a07d6 100644 --- a/img/app/image/etc/mdev.conf +++ b/img/app/image/etc/mdev.conf @@ -4,7 +4,7 @@ -$MODALIAS=.* 0:0 0 ! +importas -Siu MODALIAS modprobe -q $MODALIAS $INTERFACE=.* 0:0 0 ! +/etc/mdev/iface $MODALIAS=virtio:d0000001Av.* 0:0 0 ! +/etc/mdev/virtiofs -dri/card0 wayland:wayland 660 +background { /etc/mdev/listen card0 } +dri/card0 user:user 660 +background { /etc/mdev/listen card0 } -SUBSYSTEM=sound;.* pipewire:pipewire 660 snd/controlC0 pipewire:pipewire 660 +background { /etc/mdev/listen controlC0 } diff --git a/img/app/image/etc/passwd b/img/app/image/etc/passwd index 08324b0..425908e 100644 --- a/img/app/image/etc/passwd +++ b/img/app/image/etc/passwd @@ -1,5 +1,4 @@ root:x:0:0:System administrator:/run/root:/bin/sh -wayland:x:1:1:wayland-proxy-virtwl service user:/:/usr/bin/nologin wireplumber:x:2:2:WirePlumber service user:/:/usr/bin/nologin pipewire:x:3:3:PipeWire service user:/:/usr/bin/nologin user:x:1000:1000:Spectrum application user:/home/user:/bin/sh diff --git a/img/app/image/etc/s6-rc/wayland-proxy-virtwl/run b/img/app/image/etc/s6-rc/wayland-proxy-virtwl/run index 86d7f63..5d06b7a 100755 --- a/img/app/image/etc/s6-rc/wayland-proxy-virtwl/run +++ b/img/app/image/etc/s6-rc/wayland-proxy-virtwl/run @@ -26,6 +26,6 @@ export LISTEN_FDS 2 export LISTEN_FDNAMES wayland:x11 getpid LISTEN_PID -s6-setuidgid wayland +s6-setuidgid user wayland-proxy-virtwl --virtio-gpu --x-display=0 base-commit: 5104fa720ce8b00612c5487fc47124fbf99e58c6 -- 2.51.0

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[REGRESSION] Networking for Firefox broken on second VM run
by Alyssa Ross 09 Dec '25

09 Dec '25

Since we introduced the userspace router, if I start the Firefox VM, quit Firefox, wait for the VM to shut down, and then start it again, networking no longer works, and I see repeating log lines like this: 2025-12-09 09:13:29.147240893 [2025-12-09T09:13:29Z WARN spectrum_router::router] interface App(0) has been blocked for 1 sec, dropping packet Full reproduction steps: 1. cd host/rootfs 2. nix-shell --run 'make clean && make run' 3. Start Firefox VM with vm-start 4. See that networking works 5. Quit Firefox and wait a few seconds for VM to stop 6. Start Firefox VM with vm-start again 7. No more networking, and log lines like the above

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[PATCH] img/app: Delete dependency on nonexistent nftables service
by Demi Marie Obenour 09 Dec '25

09 Dec '25

This file was not included in the application image. Fixes: dcee941 ("vm/sys/net: integrate xdp-forwarder") Signed-off-by: Demi Marie Obenour <demiobenour(a)gmail.com> --- img/app/image/etc/s6-rc/mdevd/dependencies.d/nftables | 0 1 file changed, 0 insertions(+), 0 deletions(-) diff --git a/img/app/image/etc/s6-rc/mdevd/dependencies.d/nftables b/img/app/image/etc/s6-rc/mdevd/dependencies.d/nftables deleted file mode 100644 index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..0000000000000000000000000000000000000000 --- base-commit: 44f32b7a4b3cfbb4046447318e6753dd0eb71add change-id: 20251201-fix-file-list-3fdfd53bd150 -- Sincerely, Demi Marie Obenour (she/her/hers)

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[PATCH] vm/sys/net: start nftables service
by Yureka Lilian 09 Dec '25

09 Dec '25

This was supposed to be here all along to ensure the net-vm does not create any traffic on any interfaces except for the xdp-forwarder setup. Fixes: dcee941 ("vm/sys/net: integrate xdp-forwarder") Signed-off-by: Yureka Lilian <yureka(a)cyberchaos.dev> --- vm/sys/net/file-list.mk | 1 + vm/sys/net/image/etc/s6-rc/mdevd/dependencies.d/nftables | 0 2 files changed, 1 insertion(+) create mode 100644 vm/sys/net/image/etc/s6-rc/mdevd/dependencies.d/nftables diff --git a/vm/sys/net/file-list.mk b/vm/sys/net/file-list.mk index 7cc3520..dfea2a8 100644 --- a/vm/sys/net/file-list.mk +++ b/vm/sys/net/file-list.mk @@ -26,6 +26,7 @@ S6_RC_FILES = \ image/etc/s6-rc/mdevd-coldplug/dependencies.d/mdevd \ image/etc/s6-rc/mdevd-coldplug/type \ image/etc/s6-rc/mdevd-coldplug/up \ + image/etc/s6-rc/mdevd/dependencies.d/nftables \ image/etc/s6-rc/mdevd/notification-fd \ image/etc/s6-rc/mdevd/run \ image/etc/s6-rc/mdevd/type \ diff --git a/vm/sys/net/image/etc/s6-rc/mdevd/dependencies.d/nftables b/vm/sys/net/image/etc/s6-rc/mdevd/dependencies.d/nftables new file mode 100644 index 0000000..e69de29 -- 2.51.2

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