From 1339344a7fd3d0b578a2ee86185a582383a37cc8 Mon Sep 17 00:00:00 2001
From: Yaokun Zhang - nju <76199015+yaokunzhang@users.noreply.github.com>
Date: Tue, 12 May 2026 22:28:59 +0800
Subject: [PATCH] Add advisory for potato: RefStr::from_slice() allows invalid
 UTF-8 from safe code

---
 crates/potato/RUSTSEC-0000-0000.md | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 crates/potato/RUSTSEC-0000-0000.md

diff --git a/crates/potato/RUSTSEC-0000-0000.md b/crates/potato/RUSTSEC-0000-0000.md
new file mode 100644
index 0000000000..12723083d8
--- /dev/null
+++ b/crates/potato/RUSTSEC-0000-0000.md
@@ -0,0 +1,27 @@
+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "potato"
+date = "2026-05-02"
+url = "https://github.com/fawdlstty/potato/issues/1"
+informational = "unsound"
+categories = ["memory-corruption"]
+keywords = ["undefined-behavior", "utf-8"]
+
+[versions]
+patched = []
+```
+
+# `RefStr::from_slice()` allows constructing invalid UTF-8 from safe code
+
+`RefStr::from_slice(data, start, len)` is declared safe but uses
+`unsafe { data.get_unchecked(start) }` internally without validating `start`
+and `len`. Callers can construct a `RefStr` pointing to arbitrary bytes.
+
+Combined with `to_str()`, which calls `std::str::from_utf8_unchecked()` on
+the underlying bytes, a caller can produce an invalid `&str` that violates
+Rust's safety requirements. For example, slicing a multi-byte UTF-8 character
+in the middle produces an invalid `&str`.
+
+Both `from_slice()` and `to_str()` are public safe APIs, so this undefined
+behavior can be triggered without writing any `unsafe` code.
\ No newline at end of file