Skip to content

Introduce PyUtf8Str and fix(sqlite): validate surrogates in SQL statements #5969

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
youknowone merged 5 commits into from
Jul 14, 2025
Merged

Introduce PyUtf8Str and fix(sqlite): validate surrogates in SQL statements #5969

Show file tree
Hide file tree
Changes from 4 commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
b78f4db
fix(sqlite): validate surrogates in SQL statements
ever0de Jul 14, 2025
716efc4
Add `PyUtf8Str` wrapper for safe conversion
ever0de Jul 14, 2025
62b8a56
discord review,
ever0de Jul 14, 2025
a50a7bc
cargo check
ever0de Jul 14, 2025
3899fbe
fix review
ever0de Jul 14, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 0 additions & 2 deletions Lib/test/test_sqlite3/test_regression.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -343,8 +343,6 @@ def test_null_character(self):
self.assertRaisesRegex(sqlite.ProgrammingError, "null char",
cur.execute, query)

# TODO: RUSTPYTHON
@unittest.expectedFailure
def test_surrogates(self):
con = sqlite.connect(":memory:")
self.assertRaises(UnicodeEncodeError, con, "select '\ud8ff'")
Expand Down
9 changes: 5 additions & 4 deletions stdlib/src/sqlite.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -844,7 +844,7 @@ mod _sqlite {
type Args = (PyStrRef,);

fn call(zelf: &Py<Self>, args: Self::Args, vm: &VirtualMachine) -> PyResult {
if let Some(stmt) = Statement::new(zelf, &args.0, vm)? {
if let Some(stmt) = Statement::new(zelf, args.0, vm)? {
Ok(stmt.into_ref(&vm.ctx).into())
} else {
Ok(vm.ctx.none())
Expand Down Expand Up @@ -1480,7 +1480,7 @@ mod _sqlite {
stmt.lock().reset();
}

let Some(stmt) = Statement::new(&zelf.connection, &sql, vm)? else {
let Some(stmt) = Statement::new(&zelf.connection, sql, vm)? else {
drop(inner);
return Ok(zelf);
};
Expand Down Expand Up @@ -1552,7 +1552,7 @@ mod _sqlite {
stmt.lock().reset();
}

let Some(stmt) = Statement::new(&zelf.connection, &sql, vm)? else {
let Some(stmt) = Statement::new(&zelf.connection, sql, vm)? else {
drop(inner);
return Ok(zelf);
};
Expand Down Expand Up @@ -2291,9 +2291,10 @@ mod _sqlite {
impl Statement {
fn new(
connection: &Connection,
sql: &PyStr,
sql: PyStrRef,
vm: &VirtualMachine,
) -> PyResult<Option<Self>> {
let sql = sql.try_into_utf8(vm)?;
let sql_cstr = sql.to_cstring(vm)?;
let sql_len = sql.byte_len() + 1;

Expand Down
48 changes: 42 additions & 6 deletions vm/src/builtins/str.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -37,8 +37,8 @@ use rustpython_common::{
str::DeduceStrKind,
wtf8::{CodePoint, Wtf8, Wtf8Buf, Wtf8Chunk},
};
use std::sync::LazyLock;
use std::{borrow::Cow, char, fmt, ops::Range};
use std::{mem, sync::LazyLock};
use unic_ucd_bidi::BidiClass;
use unic_ucd_category::GeneralCategory;
use unic_ucd_ident::{is_xid_continue, is_xid_start};
Expand Down Expand Up @@ -80,6 +80,29 @@ impl fmt::Debug for PyStr {
}
}

#[repr(transparent)]
#[derive(Debug)]
pub struct PyUtf8Str(PyStr);

impl std::ops::Deref for PyUtf8Str {
Copy link
Copy Markdown
Member

@youknowone youknowone Jul 14, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Suggested change
impl std::ops::Deref for PyUtf8Str {
// TODO: Remove this Deref which may hide missing optimized methods of PyUtf8Str
impl std::ops::Deref for PyUtf8Str {

type Target = PyStr;
fn deref(&self) -> &Self::Target {
&self.0
}
}

impl PyUtf8Str {
/// Returns the underlying string slice. This is safe because the
/// type invariant guarantees UTF-8 validity.
pub fn as_str(&self) -> &str {
debug_assert!(
self.0.is_utf8(),
"PyUtf8Str invariant violated: inner string is not valid UTF-8"
);
unsafe { self.0.to_str().unwrap_unchecked() }
}
Copy link
Copy Markdown
Member

@youknowone youknowone Jul 14, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The safety is trivial for users, but not for devs

Suggested change
/// Returns the underlying string slice. This is safe because the
/// type invariant guarantees UTF-8 validity.
pub fn as_str(&self) -> &str {
debug_assert!(
self.0.is_utf8(),
"PyUtf8Str invariant violated: inner string is not valid UTF-8"
);
unsafe { self.0.to_str().unwrap_unchecked() }
}
/// Returns the underlying string slice.
pub fn as_str(&self) -> &str {
debug_assert!(
self.0.is_utf8(),
"PyUtf8Str invariant violated: inner string is not valid UTF-8"
);
// Safety: This is safe because the type invariant guarantees UTF-8 validity.
unsafe { self.0.to_str().unwrap_unchecked() }
}

}

impl AsRef<str> for PyStr {
#[track_caller] // <- can remove this once it doesn't panic
fn as_ref(&self) -> &str {
Expand Down Expand Up @@ -433,21 +456,29 @@ impl PyStr {
self.data.as_str()
}

pub fn try_to_str(&self, vm: &VirtualMachine) -> PyResult<&str> {
self.to_str().ok_or_else(|| {
fn ensure_valid_utf8(&self, vm: &VirtualMachine) -> PyResult<()> {
if self.is_utf8() {
Ok(())
} else {
let start = self
.as_wtf8()
.code_points()
.position(|c| c.to_char().is_none())
.unwrap();
vm.new_unicode_encode_error_real(
Err(vm.new_unicode_encode_error_real(
identifier!(vm, utf_8).to_owned(),
vm.ctx.new_str(self.data.clone()),
start,
start + 1,
vm.ctx.new_str("surrogates not allowed"),
)
})
))
}
}

pub fn try_to_str(&self, vm: &VirtualMachine) -> PyResult<&str> {
self.ensure_valid_utf8(vm)?;
// SAFETY: ensure_valid_utf8 passed, so unwrap is safe.
Ok(unsafe { self.to_str().unwrap_unchecked() })
}

pub fn to_string_lossy(&self) -> Cow<'_, str> {
Expand Down Expand Up @@ -1486,6 +1517,11 @@ impl PyStrRef {
s.push_wtf8(other);
*self = PyStr::from(s).into_ref(&vm.ctx);
}

pub fn try_into_utf8(self, vm: &VirtualMachine) -> PyResult<PyRef<PyUtf8Str>> {
self.ensure_valid_utf8(vm)?;
Ok(unsafe { mem::transmute::<PyRef<PyStr>, PyRef<PyUtf8Str>>(self) })
}
}

impl Representable for PyStr {
Expand Down
Loading