diff options
| -rw-r--r-- | CHANGELOG.md | 2 | ||||
| -rw-r--r-- | src/sys/socket/addr.rs | 53 | ||||
| -rw-r--r-- | src/sys/socket/mod.rs | 11 | ||||
| -rw-r--r-- | test/sys/test_socket.rs | 43 |
4 files changed, 104 insertions, 5 deletions
diff --git a/CHANGELOG.md b/CHANGELOG.md index 94927bd6..56b9b7d9 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -41,6 +41,8 @@ This project adheres to [Semantic Versioning](https://semver.org/). ### Fixed - Fix: send `ETH_P_ALL` in htons format ([#1925](https://github.com/nix-rust/nix/pull/1925)) +- Fix: `recvmsg` now sets the length of the received `sockaddr_un` field + correctly on Linux platforms. ([#2041](https://github.com/nix-rust/nix/pull/2041)) - Fix potentially invalid conversions in `SockaddrIn::from<std::net::SocketAddrV4>`, `SockaddrIn6::from<std::net::SockaddrV6>`, `IpMembershipRequest::new`, and diff --git a/src/sys/socket/addr.rs b/src/sys/socket/addr.rs index ff222b5e..1d86e756 100644 --- a/src/sys/socket/addr.rs +++ b/src/sys/socket/addr.rs @@ -765,6 +765,22 @@ impl SockaddrLike for UnixAddr { { mem::size_of::<libc::sockaddr_un>() as libc::socklen_t } + + unsafe fn set_length(&mut self, new_length: usize) -> std::result::Result<(), SocketAddressLengthNotDynamic> { + // `new_length` is only used on some platforms, so it must be provided even when not used + #![allow(unused_variables)] + cfg_if! { + if #[cfg(any(target_os = "android", + target_os = "fuchsia", + target_os = "illumos", + target_os = "linux", + target_os = "redox", + ))] { + self.sun_len = new_length as u8; + } + }; + Ok(()) + } } impl AsRef<libc::sockaddr_un> for UnixAddr { @@ -914,7 +930,32 @@ pub trait SockaddrLike: private::SockaddrLikePriv { { mem::size_of::<Self>() as libc::socklen_t } + + /// Set the length of this socket address + /// + /// This method may only be called on socket addresses whose lengths are dynamic, and it + /// returns an error if called on a type whose length is static. + /// + /// # Safety + /// + /// `new_length` must be a valid length for this type of address. Specifically, reads of that + /// length from `self` must be valid. + #[doc(hidden)] + unsafe fn set_length(&mut self, _new_length: usize) -> std::result::Result<(), SocketAddressLengthNotDynamic> { + Err(SocketAddressLengthNotDynamic) + } +} + +/// The error returned by [`SockaddrLike::set_length`] on an address whose length is statically +/// fixed. +#[derive(Copy, Clone, Debug)] +pub struct SocketAddressLengthNotDynamic; +impl fmt::Display for SocketAddressLengthNotDynamic { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.write_str("Attempted to set length on socket whose length is statically fixed") + } } +impl std::error::Error for SocketAddressLengthNotDynamic {} impl private::SockaddrLikePriv for () { fn as_mut_ptr(&mut self) -> *mut libc::sockaddr { @@ -1360,6 +1401,15 @@ impl SockaddrLike for SockaddrStorage { None => mem::size_of_val(self) as libc::socklen_t, } } + + unsafe fn set_length(&mut self, new_length: usize) -> std::result::Result<(), SocketAddressLengthNotDynamic> { + match self.as_unix_addr_mut() { + Some(addr) => { + addr.set_length(new_length) + }, + None => Err(SocketAddressLengthNotDynamic), + } + } } macro_rules! accessors { @@ -1678,7 +1728,7 @@ impl PartialEq for SockaddrStorage { } } -mod private { +pub(super) mod private { pub trait SockaddrLikePriv { /// Returns a mutable raw pointer to the inner structure. /// @@ -2215,7 +2265,6 @@ mod datalink { &self.0 } } - } } diff --git a/src/sys/socket/mod.rs b/src/sys/socket/mod.rs index 06b93c6f..c304f6e3 100644 --- a/src/sys/socket/mod.rs +++ b/src/sys/socket/mod.rs @@ -1613,7 +1613,7 @@ impl<S> MultiHeaders<S> { { // we will be storing pointers to addresses inside mhdr - convert it into boxed // slice so it can'be changed later by pushing anything into self.addresses - let mut addresses = vec![std::mem::MaybeUninit::uninit(); num_slices].into_boxed_slice(); + let mut addresses = vec![std::mem::MaybeUninit::<S>::uninit(); num_slices].into_boxed_slice(); let msg_controllen = cmsg_buffer.as_ref().map_or(0, |v| v.capacity()); @@ -1918,7 +1918,7 @@ unsafe fn read_mhdr<'a, 'i, S>( mhdr: msghdr, r: isize, msg_controllen: usize, - address: S, + mut address: S, ) -> RecvMsg<'a, 'i, S> where S: SockaddrLike { @@ -1934,6 +1934,11 @@ unsafe fn read_mhdr<'a, 'i, S>( }.as_ref() }; + // Ignore errors if this socket address has statically-known length + // + // This is to ensure that unix socket addresses have their length set appropriately. + let _ = address.set_length(mhdr.msg_namelen as usize); + RecvMsg { bytes: r as usize, cmsghdr, @@ -1969,7 +1974,7 @@ unsafe fn pack_mhdr_to_receive<S>( // initialize it. let mut mhdr = mem::MaybeUninit::<msghdr>::zeroed(); let p = mhdr.as_mut_ptr(); - (*p).msg_name = (*address).as_mut_ptr() as *mut c_void; + (*p).msg_name = address as *mut c_void; (*p).msg_namelen = S::size(); (*p).msg_iov = iov_buffer as *mut iovec; (*p).msg_iovlen = iov_buffer_len as _; diff --git a/test/sys/test_socket.rs b/test/sys/test_socket.rs index 9fb7e89a..ad7b457e 100644 --- a/test/sys/test_socket.rs +++ b/test/sys/test_socket.rs @@ -203,6 +203,49 @@ pub fn test_socketpair() { } #[test] +pub fn test_recvmsg_sockaddr_un() { + use nix::sys::socket::{ + self, bind, socket, AddressFamily, MsgFlags, SockFlag, SockType, + }; + + let tempdir = tempfile::tempdir().unwrap(); + let sockname = tempdir.path().join("sock"); + let sock = socket( + AddressFamily::Unix, + SockType::Datagram, + SockFlag::empty(), + None, + ) + .expect("socket failed"); + let sockaddr = UnixAddr::new(&sockname).unwrap(); + bind(sock, &sockaddr).expect("bind failed"); + + // Send a message + let send_buffer = "hello".as_bytes(); + if let Err(e) = socket::sendmsg( + sock, + &[std::io::IoSlice::new(send_buffer)], + &[], + MsgFlags::empty(), + Some(&sockaddr), + ) { + crate::skip!("Couldn't send ({e:?}), so skipping test"); + } + + // Receive the message + let mut recv_buffer = [0u8; 32]; + let received = socket::recvmsg( + sock, + &mut [std::io::IoSliceMut::new(&mut recv_buffer)], + None, + MsgFlags::empty(), + ) + .unwrap(); + // Check the address in the received message + assert_eq!(sockaddr, received.address.unwrap()); +} + +#[test] pub fn test_std_conversions() { use nix::sys::socket::*; |