Handle .cargo-ok being truncated

src/cargo/sources/registry/mod.rs

@@ -162,12 +162,12 @@ use std::borrow::Cow;
 use std::collections::BTreeMap;
 use std::collections::HashSet;
 use std::fs::{File, OpenOptions};
-use std::io::Write;
+use std::io::{self, Write};
 use std::path::{Path, PathBuf};
 use std::task::Poll;
 
 use anyhow::Context as _;
-use cargo_util::paths::exclude_from_backups_and_indexing;
+use cargo_util::paths::{self, exclude_from_backups_and_indexing};
 use flate2::read::GzDecoder;
 use log::debug;
 use semver::Version;
@@ -619,15 +619,22 @@ impl<'cfg> RegistrySource<'cfg> {
  // unpacked.
  let package_dir = format!("{}-{}", pkg.name(), pkg.version());
  let dst = self.src_path.join(&package_dir);
- dst.create_dir()?;
  let path = dst.join(PACKAGE_SOURCE_LOCK);
  let path = self.config.assert_package_cache_locked(&path);
  let unpack_dir = path.parent().unwrap();
- if let Ok(meta) = path.metadata() {
- if meta.len() > 0 {
- return Ok(unpack_dir.to_path_buf());
+ match path.metadata() {
+ Ok(meta) if meta.len() > 0 => return Ok(unpack_dir.to_path_buf()),
+ Ok(_meta) => {
+ // The file appears to be corrupted. Perhaps it failed to flush,
+ // or the filesystem was corrupted in some way. To be safe, let's
+ // assume something is wrong and clear it and start over.
+ log::warn!("unexpected length of {path:?}, clearing cache");
+ paths::remove_dir_all(dst.as_path_unlocked())?;
  }
+ Err(e) if e.kind() == io::ErrorKind::NotFound => {}
+ Err(e) => anyhow::bail!("failed to access package completion {path:?}: {e}"),
  }
+ dst.create_dir()?;
  let mut tar = {
  let size_limit = max_unpack_size(tarball.metadata()?.len());
  let gz = GzDecoder::new(tarball);

tests/testsuite/registry.rs

@@ -2866,3 +2866,48 @@ required by package `foo v0.1.0 ([ROOT]/foo)`
  .with_status(101)
  .run();
 }
+
+#[cargo_test]
+fn corrupted_ok_overwritten() {
+ // Checks what happens if .cargo-ok gets truncated, such as if the file is
+ // created, but the flush/close is interrupted.
+ Package::new("bar", "1.0.0").publish();
+ let p = project()
+ .file(
+ "Cargo.toml",
+ r#"
+ [package]
+ name = "foo"
+ version = "0.1.0"
+
+ [dependencies]
+ bar = "1"
+ "#,
+ )
+ .file("src/lib.rs", "")
+ .build();
+ p.cargo("fetch")
+ .with_stderr(
+ "\
+[UPDATING] `dummy-registry` index
+[DOWNLOADING] crates ...
+[DOWNLOADED] bar v1.0.0 (registry `dummy-registry`)
+",
+ )
+ .run();
+ let ok = glob::glob(
+ paths::home()
+ .join(".cargo/registry/src/*/bar-1.0.0/.cargo-ok")
+ .to_str()
+ .unwrap(),
+ )
+ .unwrap()
+ .next()
+ .unwrap()
+ .unwrap();
+ // Simulate cargo being interrupted, or filesystem corruption.
+ fs::write(&ok, "").unwrap();
+ assert_eq!(fs::read_to_string(&ok).unwrap(), "");
+ p.cargo("fetch").with_stderr("").run();
+ assert_eq!(fs::read_to_string(&ok).unwrap(), "ok");
+}