Reported

August 5, 2025

Issued

August 22, 2025

Package

xcb (crates.io)

Type

INFO Unsound

References

• https://github.com/rust-x-bindings/rust-xcb/issues/282
• https://github.com/rust-x-bindings/rust-xcb/issues/167
• https://github.com/rust-x-bindings/rust-xcb/pull/283

Patched

• >=1.6.0

Affected Functions

Version

xcb::Connection::connect_to_fd

• >=1.0.0-beta.0

xcb::Connection::connect_to_fd_with_extensions

• >=1.0.0-beta.0

Description

The API of xcb::Connection has constructors which allow an arbitrary RawFd to be used as a socket connection. On either failure of these constructors or on the drop of Connection, it closes the associated file descriptor. Thus, a program which uses an OwnedFd (such as a UnixStream) as the file descriptor can close the file descriptor and continue to attempt using it or close an already-closed file descriptor, violating I/O safety.

Starting in version 1.6.0, xcb provides Connection::connect_with_fd and Connection::connect_with_fd_and_extensions as safe alternatives and deprecates the problematic functions.

Advisory available under CC0-1.0 license.