Soundness: Creating`BinaryArray` from `ArrayData` does not perform bound checks on reading offsets

[jorgecarleitao]

When an ArrayData reports a length inconsistent with the length of the offsets buffer, value_offsets reads out of bounds.

use arrow::array::*;
use arrow::buffer::*;
use arrow::datatypes::*;

fn main() {
    let data = ArrayData::new(
        DataType::Binary,
        1000,
        None,
        None,
        0,
        vec![
            Buffer::from_slice_ref(&[0i32, 1]),
            Buffer::from_slice_ref(&[0u8, 1, 1]),
        ],
        vec![],
    );
    let a = BinaryArray::from(data);
    let b = a.value(10);
}

cargo miri run --example unsafe

error: Undefined Behavior: memory access failed: pointer must be in-bounds at offset 4004, but is outside bounds of alloc1459 which has size 64
  --> /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/slice/raw.rs:95:14
   |
95 |     unsafe { &*ptr::slice_from_raw_parts(data, len) }
   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: pointer must be in-bounds at offset 4004, but is outside bounds of alloc1459 which has size 64
   |
   = 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: inside `std::slice::from_raw_parts::<i32>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/slice/raw.rs:95:14
   = note: inside `arrow::array::GenericBinaryArray::<i32>::value_offsets` at /home/azureuser/projects/arrow-rs/arrow/src/array/array_binary.rs:71:13
   = note: inside `arrow::array::GenericBinaryArray::<i32>::value` at /home/azureuser/projects/arrow-rs/arrow/src/array/array_binary.rs:104:28
note: inside `main` at arrow/examples/unsafe.rs:19:13
  --> arrow/examples/unsafe.rs:19:13
   |
19 |     let b = a.value(10);
   |             ^^^^^^^^^^^
   = note: inside `<fn() as std::ops::FnOnce<()>>::call_once - shim(fn())` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ops/function.rs:227:5
   = note: inside `std::sys_common::backtrace::__rust_begin_short_backtrace::<fn(), ()>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sys_common/backtrace.rs:125:18
   = note: inside closure at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/rt.rs:63:18
   = note: inside `std::ops::function::impls::<impl std::ops::FnOnce<()> for &dyn std::ops::Fn() -> i32 + std::marker::Sync + std::panic::RefUnwindSafe>::call_once` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ops/function.rs:259:13
   = note: inside `std::panicking::r#try::do_call::<&dyn std::ops::Fn() -> i32 + std::marker::Sync + std::panic::RefUnwindSafe, i32>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:401:40
   = note: inside `std::panicking::r#try::<i32, &dyn std::ops::Fn() -> i32 + std::marker::Sync + std::panic::RefUnwindSafe>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:365:19
   = note: inside `std::panic::catch_unwind::<&dyn std::ops::Fn() -> i32 + std::marker::Sync + std::panic::RefUnwindSafe, i32>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panic.rs:434:14
   = note: inside closure at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/rt.rs:45:48
   = note: inside `std::panicking::r#try::do_call::<[closure@std::rt::lang_start_internal::{closure#2}], isize>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:401:40
   = note: inside `std::panicking::r#try::<isize, [closure@std::rt::lang_start_internal::{closure#2}]>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panicking.rs:365:19
   = note: inside `std::panic::catch_unwind::<[closure@std::rt::lang_start_internal::{closure#2}], isize>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/panic.rs:434:14
   = note: inside `std::rt::lang_start_internal` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/rt.rs:45:20
   = note: inside `std::rt::lang_start::<()>` at /home/azureuser/.rustup/toolchains/nightly-2021-07-04-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/rt.rs:62:5

error: aborting due to previous error; 1 warning emitted

Affects all versions up to today.

[alamb]

Updating title of the ticket to make it clear this affects misusing the lower level APIs, as described in https://github.com/apache/arrow-rs/tree/master/arrow#safety

[alamb]

This is a specific case of the general issue described in #817, so closing this one as a duplicate in favor of the more general ticket.