[arrow-buffer] Integer overflow in BitChunks::new leads to undefined behavior

[ksj1230]

Description

This issue was previously reported privately and is now being disclosed following coordination with maintainers.

BitChunks::new() computes offset + length without overflow checking.
When the sum wraps, bounds validation may be bypassed, leading to an inconsistent internal state.

This can result in a potential out-of-bounds read via safe Rust APIs.

Fix

See PR #9818

Reported by Sungjin Kim (@ksj1230)

[alamb]

Thank you @ksj1230

This was fixed in

• Prevent BitChunks length overflow #9818

It was released in 58.2.0 (last week)

[alamb]

label_issue.py automatically added labels {'arrow'} from #9896