fix(git): prevent core.fsmonitor from executing external commands (#3981)

This commit is contained in:
David Knaack 2023-07-31 21:44:31 +02:00 committed by GitHub
parent 53a8808e7a
commit 03278e4de4
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3 changed files with 116 additions and 40 deletions

View File

@ -313,6 +313,12 @@ impl<'a> Context<'a> {
let branch = get_current_branch(&repository);
let remote = get_remote_repository_info(&repository, branch.as_deref());
let path = repository.path().to_path_buf();
let fs_monitor_value_is_true = repository
.config_snapshot()
.boolean("core.fs_monitor")
.unwrap_or(false);
Ok(Repo {
repo: shared_repo,
branch,
@ -320,6 +326,7 @@ impl<'a> Context<'a> {
path,
state: repository.state(),
remote,
fs_monitor_value_is_true,
})
})
}
@ -589,6 +596,10 @@ pub struct Repo {
/// Remote repository
pub remote: Option<Remote>,
/// Contains `true` if the value of `core.fsmonitor` is set to `true`.
/// If not `true`, `fsmonitor` is explicitly disabled in git commands.
fs_monitor_value_is_true: bool,
}
impl Repo {
@ -596,6 +607,47 @@ impl Repo {
pub fn open(&self) -> Repository {
self.repo.to_thread_local()
}
/// Wrapper to execute external git commands.
/// Handles adding the appropriate `--git-dir` and `--work-tree` flags to the command.
/// Also handles additional features required for security, such as disabling `fsmonitor`.
/// At this time, mocking is not supported.
pub fn exec_git<T: AsRef<OsStr> + Debug>(
&self,
context: &Context,
git_args: &[T],
) -> Option<CommandOutput> {
let mut command = create_command("git").ok()?;
// A value of `true` should not execute external commands.
let fsm_config_value = if self.fs_monitor_value_is_true {
"core.fsmonitor=true"
} else {
"core.fsmonitor="
};
command.env("GIT_OPTIONAL_LOCKS", "0").args([
OsStr::new("-C"),
context.current_dir.as_os_str(),
OsStr::new("--git-dir"),
self.path.as_os_str(),
OsStr::new("-c"),
OsStr::new(fsm_config_value),
]);
// Bare repositories might not have a workdir, so we need to check for that.
if let Some(wt) = self.workdir.as_ref() {
command.args([OsStr::new("--work-tree"), wt.as_os_str()]);
}
command.args(git_args);
log::trace!("Executing git command: {:?}", command);
exec_timeout(
&mut command,
Duration::from_millis(context.root_config.command_timeout),
)
}
}
/// Remote repository

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@ -1,5 +1,4 @@
use regex::Regex;
use std::ffi::OsStr;
use crate::{
config::ModuleConfig, configs::git_metrics::GitMetricsConfig,
@ -21,23 +20,12 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
};
let repo = context.get_repo().ok()?;
let repo_root = repo.workdir.as_ref()?;
let mut args = vec![
OsStr::new("--git-dir"),
repo.path.as_os_str(),
OsStr::new("--work-tree"),
repo_root.as_os_str(),
OsStr::new("--no-optional-locks"),
OsStr::new("diff"),
OsStr::new("--shortstat"),
];
let mut git_args = vec!["diff", "--shortstat"];
if config.ignore_submodules {
args.push(OsStr::new("--ignore-submodules"));
git_args.push("--ignore-submodules");
}
let diff = context.exec_cmd("git", &args)?.stdout;
let diff = repo.exec_git(context, &git_args)?.stdout;
let stats = GitDiff::parse(&diff);

View File

@ -4,9 +4,9 @@ use regex::Regex;
use super::{Context, Module, ModuleConfig};
use crate::configs::git_status::GitStatusConfig;
use crate::context;
use crate::formatter::StringFormatter;
use crate::segment::Segment;
use std::ffi::OsStr;
use std::sync::Arc;
const ALL_STATUS_FORMAT: &str =
@ -31,10 +31,8 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
let mut module = context.new_module("git_status");
let config: GitStatusConfig = GitStatusConfig::try_load(module.config);
let info = Arc::new(GitStatusInfo::load(context, config.clone()));
//Return None if not in git repository
context.get_repo().ok()?;
// Return None if not in git repository
let repo = context.get_repo().ok()?;
if let Some(git_status) = git_status_wsl(context, &config) {
if git_status.is_empty() {
@ -44,6 +42,8 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
return Some(module);
}
let info = Arc::new(GitStatusInfo::load(context, repo, config.clone()));
let parsed = StringFormatter::new(config.format).and_then(|formatter| {
formatter
.map_meta(|variable, _| match variable {
@ -128,15 +128,21 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
struct GitStatusInfo<'a> {
context: &'a Context<'a>,
repo: &'a context::Repo,
config: GitStatusConfig<'a>,
repo_status: OnceCell<Option<RepoStatus>>,
stashed_count: OnceCell<Option<usize>>,
}
impl<'a> GitStatusInfo<'a> {
pub fn load(context: &'a Context, config: GitStatusConfig<'a>) -> Self {
pub fn load(
context: &'a Context,
repo: &'a context::Repo,
config: GitStatusConfig<'a>,
) -> Self {
Self {
context,
repo,
config,
repo_status: OnceCell::new(),
stashed_count: OnceCell::new(),
@ -148,19 +154,20 @@ impl<'a> GitStatusInfo<'a> {
}
pub fn get_repo_status(&self) -> &Option<RepoStatus> {
self.repo_status
.get_or_init(|| match get_repo_status(self.context, &self.config) {
self.repo_status.get_or_init(|| {
match get_repo_status(self.context, self.repo, &self.config) {
Some(repo_status) => Some(repo_status),
None => {
log::debug!("get_repo_status: git status execution failed");
None
}
})
}
})
}
pub fn get_stashed(&self) -> &Option<usize> {
self.stashed_count
.get_or_init(|| match get_stashed_count(self.context) {
.get_or_init(|| match get_stashed_count(self.repo) {
Some(stashed_count) => Some(stashed_count),
None => {
log::debug!("get_stashed_count: git stash execution failed");
@ -199,37 +206,35 @@ impl<'a> GitStatusInfo<'a> {
}
/// Gets the number of files in various git states (staged, modified, deleted, etc...)
fn get_repo_status(context: &Context, config: &GitStatusConfig) -> Option<RepoStatus> {
fn get_repo_status(
context: &Context,
repo: &context::Repo,
config: &GitStatusConfig,
) -> Option<RepoStatus> {
log::debug!("New repo status created");
let mut repo_status = RepoStatus::default();
let mut args = vec![
OsStr::new("-C"),
context.current_dir.as_os_str(),
OsStr::new("--no-optional-locks"),
OsStr::new("status"),
OsStr::new("--porcelain=2"),
];
let mut args = vec!["status", "--porcelain=2"];
// for performance reasons, only pass flags if necessary...
let has_ahead_behind = !config.ahead.is_empty() || !config.behind.is_empty();
let has_up_to_date_diverged = !config.up_to_date.is_empty() || !config.diverged.is_empty();
if has_ahead_behind || has_up_to_date_diverged {
args.push(OsStr::new("--branch"));
args.push("--branch");
}
// ... and add flags that omit information the user doesn't want
let has_untracked = !config.untracked.is_empty();
if !has_untracked {
args.push(OsStr::new("--untracked-files=no"));
args.push("--untracked-files=no");
}
if config.ignore_submodules {
args.push(OsStr::new("--ignore-submodules=dirty"));
args.push("--ignore-submodules=dirty");
} else if !has_untracked {
args.push(OsStr::new("--ignore-submodules=untracked"));
args.push("--ignore-submodules=untracked");
}
let status_output = context.exec_cmd("git", &args)?;
let status_output = repo.exec_git(context, &args)?;
let statuses = status_output.stdout.lines();
statuses.for_each(|status| {
@ -243,8 +248,8 @@ fn get_repo_status(context: &Context, config: &GitStatusConfig) -> Option<RepoSt
Some(repo_status)
}
fn get_stashed_count(context: &Context) -> Option<usize> {
let repo = context.get_repo().ok()?.open();
fn get_stashed_count(repo: &context::Repo) -> Option<usize> {
let repo = repo.open();
let reference = match repo.try_find_reference("refs/stash") {
Ok(Some(reference)) => reference,
// No stash reference found
@ -742,6 +747,37 @@ mod tests {
repo_dir.close()
}
#[test]
#[cfg(unix)]
fn doesnt_run_fsmonitor() -> io::Result<()> {
use std::os::unix::fs::PermissionsExt;
let repo_dir = fixture_repo(FixtureProvider::Git)?;
let mut f = File::create(repo_dir.path().join("do_not_execute"))?;
write!(f, "#!/bin/sh\necho executed > executed\nsync executed")?;
let metadata = f.metadata()?;
let mut permissions = metadata.permissions();
permissions.set_mode(0o700);
f.set_permissions(permissions)?;
f.sync_all()?;
create_command("git")?
.args(["config", "core.fsmonitor"])
.arg(repo_dir.path().join("do_not_execute"))
.current_dir(repo_dir.path())
.output()?;
ModuleRenderer::new("git_status")
.path(repo_dir.path())
.collect();
let created_file = repo_dir.path().join("executed").exists();
assert!(!created_file);
repo_dir.close()
}
#[test]
fn shows_stashed() -> io::Result<()> {
let repo_dir = fixture_repo(FixtureProvider::Git)?;