From 1826f079d38ac7d4f74155677a8f66300780b8b0 Mon Sep 17 00:00:00 2001
From: kellito <kellito@redbearos.org>
Date: Sun, 5 Jul 2026 19:14:30 +0300
Subject: [PATCH] =?UTF-8?q?tlc:=20Sprint=203=20C15=20=E2=80=94=20TarVfs::o?=
 =?UTF-8?q?pen=20rejects=20empty/garbage=20archives?=
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The tar crate returns an empty iterator (without erroring) for
both zero-byte files and files that aren't valid tar archives.
TarVfs::open() previously succeeded in both cases, producing an
'unbrowsable' archive the user couldn't navigate.

Fix:
  TarVfs::open() now checks entries.is_empty() after list() and
  returns VfsError::Other('empty tar archive') when empty. This
  covers both truly empty files (corrupt/truncated) and garbage
  bytes (e.g., text mistakenly saved with .tar extension).

Tests (2 new in vfs::tar::tests):
  - tar_vfs_open_empty_file_errors
  - tar_vfs_open_garbage_bytes_errors

Total: 1281 passing (was 1279; +2 new).
---
 local/recipes/tui/tlc/source/src/vfs/tar.rs | 30 +++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/local/recipes/tui/tlc/source/src/vfs/tar.rs b/local/recipes/tui/tlc/source/src/vfs/tar.rs
index 849a2c51f5..54bffd5324 100644
--- a/local/recipes/tui/tlc/source/src/vfs/tar.rs
+++ b/local/recipes/tui/tlc/source/src/vfs/tar.rs
@@ -119,6 +119,13 @@ impl TarVfs {
             kinds: HashMap::new(),
         };
         me.list()?;
+        // An empty tar (zero entries) usually indicates a corrupt or
+        // truncated archive; the tar crate returns an empty
+        // iterator without erroring. Surface this as a real error
+        // so the caller doesn't present an unbrowsable archive.
+        if me.entries.is_empty() {
+            return Err(VfsError::Other("empty tar archive".to_string()));
+        }
         Ok(me)
     }
 
@@ -449,6 +456,29 @@ mod tests {
         assert!(r.is_err());
     }
 
+    #[test]
+    fn tar_vfs_open_empty_file_errors() {
+        // An empty file is not a valid tar archive; opening must
+        // return an error rather than silently producing an empty
+        // (unbrowsable) archive.
+        let p = std::env::temp_dir().join("tlc-tar-empty.tar");
+        std::fs::write(&p, b"").unwrap();
+        let r = TarVfs::open(p.clone());
+        assert!(r.is_err(), "empty file must error on TarVfs::open");
+        let _ = std::fs::remove_file(&p);
+    }
+
+    #[test]
+    fn tar_vfs_open_garbage_bytes_errors() {
+        // Random bytes that aren't a valid tar header must error
+        // rather than be silently accepted.
+        let p = std::env::temp_dir().join("tlc-tar-garbage.tar");
+        std::fs::write(&p, b"not a tar archive at all, just text").unwrap();
+        let r = TarVfs::open(p.clone());
+        assert!(r.is_err(), "garbage bytes must error on TarVfs::open");
+        let _ = std::fs::remove_file(&p);
+    }
+
     #[test]
     fn tar_vfs_extract_gz_round_trip() {
         let dir = std::env::temp_dir().join("tlc-tar-gz-test");