FFI mode does not support accessing C-allocated memory from Rust #4647
Description
error: Undefined Behavior: pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got 0x7f9b3e6b5fd0[noalloc] which is a dangling pointer (it has no provenance)
--> /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/sqlite_value.rs:98:25
|
98 | let bytes = slice::from_raw_parts(
| _________________________^
99 | | ptr,
100 | | len.try_into()
101 | | .expect("Diesel expects to run at least on a 32 bit platform"),
102 | | );
| |_____________^ Undefined Behavior occurred here
|
= help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
= help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
= note: BACKTRACE on thread `deserialization`:
= note: inside `diesel::sqlite::SqliteValue::<'_, '_, '_>::parse_string::<'_, &str, {closure@diesel::sqlite::SqliteValue<'_, '_, '_>::read_text::{closure#0}}>` at /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/sqlite_value.rs:98:25: 102:14
note: inside `diesel::sqlite::SqliteValue::<'_, '_, '_>::read_text`
Relevant diesel code:
I believe this code is sound as these pointer is returned by libsqlite3 and that's just a common way to return a string (as ptr + lenght)
Now the problem might be that the ptr is allocated and returned from the C code, so miri doesn't know much about it and assumes that it is not aligned because of that?
Full Error
test deserialization::check_deserialize_composite_ptr_types ... warning: sharing memory with a native function called via FFI
--> /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/raw.rs:53:13
|
53 | ffi::sqlite3_open_v2(database_url.as_ptr(), &mut conn_pointer, flags, ptr::null())
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ sharing memory with a native function
|
= help: when memory is shared with a native function call, Miri stops tracking initialization and provenance for that memory
= help: in particular, Miri assumes that the native call initializes all memory it has access to
= help: Miri also assumes that any part of this memory may be a pointer that is permitted to point to arbitrary exposed memory
= help: what this means is that Miri will easily miss Undefined Behavior related to incorrect usage of this shared memory, so you should not take a clean Miri run as a signal that your FFI code is UB-free
= note: BACKTRACE on thread `deserialization`:
= note: inside `diesel::sqlite::connection::raw::RawConnection::establish` at /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/raw.rs:53:13: 53:95
note: inside `diesel::SqliteConnection::establish_inner`
--> /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/mod.rs:602:30
|
602 | let raw_connection = RawConnection::establish(database_url)?;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `<diesel::SqliteConnection as diesel::Connection>::establish`
--> /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/mod.rs:225:32
|
225 | let establish_result = Self::establish_inner(database_url);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `schema::backend_specific_connection`
--> diesel_tests/tests/schema/mod.rs:284:20
|
284 | let mut conn = SqliteConnection::establish(":memory:").unwrap();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `schema::connection_without_transaction`
--> diesel_tests/tests/schema/mod.rs:253:22
|
253 | let mut result = backend_specific_connection();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `schema::connection`
--> diesel_tests/tests/schema/mod.rs:243:22
|
243 | let mut result = connection_without_transaction();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `deserialization::check_deserialize_composite_ptr_types`
--> diesel_tests/tests/deserialization.rs:70:21
|
70 | let conn = &mut connection();
| ^^^^^^^^^^^^
note: inside closure
--> diesel_tests/tests/deserialization.rs:69:43
|
68 | #[diesel_test_helper::test]
| --------------------------- in this attribute macro expansion
69 | fn check_deserialize_composite_ptr_types() {
| ^
= note: this warning originates in the attribute macro `test` which comes from the expansion of the attribute macro `diesel_test_helper::test` (in Nightly builds, run with -Z macro-backtrace for more info)
error: Undefined Behavior: pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got 0x7f9b3e6b5fd0[noalloc] which is a dangling pointer (it has no provenance)
--> /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/sqlite_value.rs:98:25
|
98 | let bytes = slice::from_raw_parts(
| _________________________^
99 | | ptr,
100 | | len.try_into()
101 | | .expect("Diesel expects to run at least on a 32 bit platform"),
102 | | );
| |_____________^ Undefined Behavior occurred here
|
= help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
= help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
= note: BACKTRACE on thread `deserialization`:
= note: inside `diesel::sqlite::SqliteValue::<'_, '_, '_>::parse_string::<'_, &str, {closure@diesel::sqlite::SqliteValue<'_, '_, '_>::read_text::{closure#0}}>` at /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/sqlite_value.rs:98:25: 102:14
note: inside `diesel::sqlite::SqliteValue::<'_, '_, '_>::read_text`
--> /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/connection/sqlite_value.rs:120:9
|
120 | self.parse_string(|s| s)
| ^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `diesel::sqlite::types::<impl diesel::deserialize::FromSql<diesel::sql_types::Text, diesel::sqlite::Sqlite> for *const str>::from_sql`
--> /home/weiznich/Documents/rust/diesel/diesel/src/sqlite/types/mod.rs:22:20
|
22 | let text = value.read_text();
| ^^^^^^^^^^^^^^^^^
note: inside `<*const str as diesel::deserialize::FromSql<diesel::sql_types::Text, diesel::sqlite::Sqlite>>::from_nullable_sql`
--> /home/weiznich/Documents/rust/diesel/diesel/src/deserialize.rs:471:28
|
471 | Some(bytes) => Self::from_sql(bytes),
| ^^^^^^^^^^^^^^^^^^^^^
note: inside `<*const str as diesel::deserialize::FromStaticSqlRow<diesel::sql_types::Text, diesel::sqlite::Sqlite>>::build_from_row::<'_, diesel::row::private::PartialRow<'_, diesel::sqlite::connection::row::SqliteRow<'_, '_>>>`
--> /home/weiznich/Documents/rust/diesel/diesel/src/deserialize.rs:574:9
|
574 | T::from_nullable_sql(field.value()).map_err(|e| {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `<*const str as diesel::deserialize::FromSqlRow<diesel::sql_types::Text, diesel::sqlite::Sqlite>>::build_from_row::<'_, diesel::row::private::PartialRow<'_, diesel::sqlite::connection::row::SqliteRow<'_, '_>>>`
--> /home/weiznich/Documents/rust/diesel/diesel/src/deserialize.rs:559:19
|
559 | let row = <T::Row as FromStaticSqlRow<ST, DB>>::build_from_row(row)?;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `diesel::type_impls::tuples::<impl diesel::deserialize::FromStaticSqlRow<(diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite> for (i32, *const str, *const [u8])>::build_from_row::<'_, diesel::sqlite::connection::row::SqliteRow<'_, '_>>`
--> /home/weiznich/Documents/rust/diesel/diesel/src/type_impls/tuples.rs:603:1
|
603 | diesel_derives::__diesel_for_each_tuple!(tuple_impls);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `<deserialization::User as diesel::deserialize::FromSqlRow<(diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>>::build_from_row::<'_, diesel::sqlite::connection::row::SqliteRow<'_, '_>>`
--> /home/weiznich/Documents/rust/diesel/diesel/src/deserialize.rs:559:19
|
559 | let row = <T::Row as FromStaticSqlRow<ST, DB>>::build_from_row(row)?;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `diesel::query_dsl::load_dsl::private::LoadIter::<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>::map_row`
--> /home/weiznich/Documents/rust/diesel/diesel/src/query_dsl/load_dsl.rs:131:21
|
131 | U::build_from_row(&row).map_err(crate::result::Error::DeserializationError),
| ^^^^^^^^^^^^^^^^^^^^^^^
note: inside `<diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite> as std::iter::Iterator>::next`
--> /home/weiznich/Documents/rust/diesel/diesel/src/query_dsl/load_dsl.rs:148:13
|
148 | Self::map_row(self.cursor.next())
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
= note: inside `<diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite> as std::iter::Iterator>::try_fold::<(), {closure@<std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>> as std::iter::Iterator>::try_fold<(), {closure@std::iter::Iterator::try_for_each::call<deserialization::User, std::ops::ControlFlow<deserialization::User>, fn(deserialization::User) -> std::ops::ControlFlow<deserialization::User> {std::ops::ControlFlow::<deserialization::User>::Break}>::{closure#0}}, std::ops::ControlFlow<deserialization::User>>::{closure#0}}, std::ops::ControlFlow<std::ops::ControlFlow<deserialization::User>>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/traits/iterator.rs:2426:29: 2426:40
= note: inside `<std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>> as std::iter::Iterator>::try_fold::<(), {closure@std::iter::Iterator::try_for_each::call<deserialization::User, std::ops::ControlFlow<deserialization::User>, fn(deserialization::User) -> std::ops::ControlFlow<deserialization::User> {std::ops::ControlFlow::<deserialization::User>::Break}>::{closure#0}}, std::ops::ControlFlow<deserialization::User>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/adapters/mod.rs:191:9: 198:15
= note: inside `<std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>> as std::iter::Iterator>::try_for_each::<fn(deserialization::User) -> std::ops::ControlFlow<deserialization::User> {std::ops::ControlFlow::<deserialization::User>::Break}, std::ops::ControlFlow<deserialization::User>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/traits/iterator.rs:2488:9: 2488:35
= note: inside `<std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>> as std::iter::Iterator>::next` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/adapters/mod.rs:174:9: 174:46
= note: inside `<std::vec::Vec<deserialization::User> as std::vec::spec_from_iter_nested::SpecFromIterNested<deserialization::User, std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>>>>::from_iter` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/vec/spec_from_iter_nested.rs:24:32: 24:47
= note: inside `<std::vec::Vec<deserialization::User> as std::vec::spec_from_iter::SpecFromIter<deserialization::User, std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>>>>::from_iter` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/vec/spec_from_iter.rs:33:9: 33:48
= note: inside `<std::vec::Vec<deserialization::User> as std::iter::FromIterator<deserialization::User>>::from_iter::<std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/alloc/src/vec/mod.rs:3689:9: 3689:76
= note: inside `<std::iter::adapters::GenericShunt<'_, diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, std::result::Result<std::convert::Infallible, diesel::result::Error>> as std::iter::Iterator>::collect::<std::vec::Vec<deserialization::User>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/traits/iterator.rs:2028:9: 2028:38
= note: inside closure at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/result.rs:2151:49: 2151:60
= note: inside `std::iter::adapters::try_process::<diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>, deserialization::User, std::result::Result<std::convert::Infallible, diesel::result::Error>, {closure@<std::result::Result<std::vec::Vec<deserialization::User>, diesel::result::Error> as std::iter::FromIterator<std::result::Result<deserialization::User, diesel::result::Error>>>::from_iter<diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>>::{closure#0}}, std::vec::Vec<deserialization::User>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/adapters/mod.rs:160:17: 160:25
= note: inside `<std::result::Result<std::vec::Vec<deserialization::User>, diesel::result::Error> as std::iter::FromIterator<std::result::Result<deserialization::User, diesel::result::Error>>>::from_iter::<diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/result.rs:2151:9: 2151:61
= note: inside `<diesel::query_dsl::load_dsl::private::LoadIter<deserialization::User, diesel::sqlite::connection::statement_iterator::StatementIterator<'_, '_>, (diesel::sql_types::Integer, diesel::sql_types::Text, diesel::sql_types::Binary), diesel::sqlite::Sqlite> as std::iter::Iterator>::collect::<std::result::Result<std::vec::Vec<deserialization::User>, diesel::result::Error>>` at /home/weiznich/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/iter/traits/iterator.rs:2028:9: 2028:38
note: inside `<diesel::query_builder::select_statement::SelectStatement<diesel::query_builder::from_clause::FromClause<deserialization::my_users::table>, diesel::query_builder::select_clause::SelectClause<diesel::expression::select_by::SelectBy<deserialization::User, diesel::sqlite::Sqlite>>> as diesel::RunQueryDsl<diesel::SqliteConnection>>::load::<'_, deserialization::User>`
--> /home/weiznich/Documents/rust/diesel/diesel/src/query_dsl/mod.rs:1594:9
|
1594 | self.internal_load(conn)?.collect()
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: inside `deserialization::check_deserialize_composite_ptr_types`
--> diesel_tests/tests/deserialization.rs:101:13
|
101 | let r = my_users::table
| _____________^
102 | | .select(User::as_select())
103 | | .load(conn)
| |___________________^
note: inside closure
--> diesel_tests/tests/deserialization.rs:69:43
|
68 | #[diesel_test_helper::test]
| --------------------------- in this attribute macro expansion
69 | fn check_deserialize_composite_ptr_types() {
| ^
= note: this error originates in the macro `impl_from_sql_row` which comes from the expansion of the attribute macro `diesel_test_helper::test` (in Nightly builds, run with -Z macro-backtrace for more info)