diff options
| -rw-r--r-- | CHANGELOG.md | 4 | ||||
| -rw-r--r-- | src/sys/socket/sockopt.rs | 79 |
2 files changed, 46 insertions, 37 deletions
diff --git a/CHANGELOG.md b/CHANGELOG.md index 3d565a9a..1498c0ca 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -25,6 +25,10 @@ This project adheres to [Semantic Versioning](http://semver.org/). ### Fixed +- Fixed `getsockopt`. The old code produced UB which triggers a panic with + Rust 1.44.0. + (#[1214](https://github.com/nix-rust/nix/pull/1214)) + - Fixed a bug in nix::unistd that would result in an infinite loop when a group or user lookup required a buffer larger than 16KB. (#[1198](https://github.com/nix-rust/nix/pull/1198)) diff --git a/src/sys/socket/sockopt.rs b/src/sys/socket/sockopt.rs index 691f66dd..6b8180b3 100644 --- a/src/sys/socket/sockopt.rs +++ b/src/sys/socket/sockopt.rs @@ -3,7 +3,10 @@ use Result; use errno::Errno; use sys::time::TimeVal; use libc::{self, c_int, c_void, socklen_t}; -use std::mem; +use std::mem::{ + self, + MaybeUninit +}; use std::os::unix::io::RawFd; use std::ffi::{OsStr, OsString}; #[cfg(target_family = "unix")] @@ -84,14 +87,14 @@ macro_rules! getsockopt_impl { fn get(&self, fd: RawFd) -> Result<$ty> { unsafe { - let mut getter: $getter = Get::blank(); + let mut getter: $getter = Get::uninit(); let res = libc::getsockopt(fd, $level, $flag, getter.ffi_ptr(), getter.ffi_len()); Errno::result(res)?; - Ok(getter.unwrap()) + Ok(getter.assume_init()) } } } @@ -364,16 +367,16 @@ impl<T> SetSockOpt for AlgSetKey<T> where T: AsRef<[u8]> + Clone { /// Helper trait that describes what is expected from a `GetSockOpt` getter. unsafe trait Get<T> { - /// Returns an empty value. - unsafe fn blank() -> Self; + /// Returns an uninitialized value. + unsafe fn uninit() -> Self; /// Returns a pointer to the stored value. This pointer will be passed to the system's /// `getsockopt` call (`man 3p getsockopt`, argument `option_value`). fn ffi_ptr(&mut self) -> *mut c_void; /// Returns length of the stored value. This pointer will be passed to the system's /// `getsockopt` call (`man 3p getsockopt`, argument `option_len`). fn ffi_len(&mut self) -> *mut socklen_t; - /// Returns the stored value. - unsafe fn unwrap(self) -> T; + /// Returns the hopefully initialized inner value. + unsafe fn assume_init(self) -> T; } /// Helper trait that describes what is expected from a `SetSockOpt` setter. @@ -391,28 +394,28 @@ unsafe trait Set<'a, T> { /// Getter for an arbitrary `struct`. struct GetStruct<T> { len: socklen_t, - val: T, + val: MaybeUninit<T>, } unsafe impl<T> Get<T> for GetStruct<T> { - unsafe fn blank() -> Self { + unsafe fn uninit() -> Self { GetStruct { len: mem::size_of::<T>() as socklen_t, - val: mem::zeroed(), + val: MaybeUninit::uninit(), } } fn ffi_ptr(&mut self) -> *mut c_void { - &mut self.val as *mut T as *mut c_void + self.val.as_mut_ptr() as *mut c_void } fn ffi_len(&mut self) -> *mut socklen_t { &mut self.len } - unsafe fn unwrap(self) -> T { + unsafe fn assume_init(self) -> T { assert_eq!(self.len as usize, mem::size_of::<T>(), "invalid getsockopt implementation"); - self.val + self.val.assume_init() } } @@ -438,28 +441,28 @@ unsafe impl<'a, T> Set<'a, T> for SetStruct<'a, T> { /// Getter for a boolean value. struct GetBool { len: socklen_t, - val: c_int, + val: MaybeUninit<c_int>, } unsafe impl Get<bool> for GetBool { - unsafe fn blank() -> Self { + unsafe fn uninit() -> Self { GetBool { len: mem::size_of::<c_int>() as socklen_t, - val: mem::zeroed(), + val: MaybeUninit::uninit(), } } fn ffi_ptr(&mut self) -> *mut c_void { - &mut self.val as *mut c_int as *mut c_void + self.val.as_mut_ptr() as *mut c_void } fn ffi_len(&mut self) -> *mut socklen_t { &mut self.len } - unsafe fn unwrap(self) -> bool { + unsafe fn assume_init(self) -> bool { assert_eq!(self.len as usize, mem::size_of::<c_int>(), "invalid getsockopt implementation"); - self.val != 0 + self.val.assume_init() != 0 } } @@ -485,28 +488,28 @@ unsafe impl<'a> Set<'a, bool> for SetBool { /// Getter for an `u8` value. struct GetU8 { len: socklen_t, - val: u8, + val: MaybeUninit<u8>, } unsafe impl Get<u8> for GetU8 { - unsafe fn blank() -> Self { + unsafe fn uninit() -> Self { GetU8 { len: mem::size_of::<u8>() as socklen_t, - val: mem::zeroed(), + val: MaybeUninit::uninit(), } } fn ffi_ptr(&mut self) -> *mut c_void { - &mut self.val as *mut u8 as *mut c_void + self.val.as_mut_ptr() as *mut c_void } fn ffi_len(&mut self) -> *mut socklen_t { &mut self.len } - unsafe fn unwrap(self) -> u8 { + unsafe fn assume_init(self) -> u8 { assert_eq!(self.len as usize, mem::size_of::<u8>(), "invalid getsockopt implementation"); - self.val as u8 + self.val.assume_init() } } @@ -532,28 +535,28 @@ unsafe impl<'a> Set<'a, u8> for SetU8 { /// Getter for an `usize` value. struct GetUsize { len: socklen_t, - val: c_int, + val: MaybeUninit<c_int>, } unsafe impl Get<usize> for GetUsize { - unsafe fn blank() -> Self { + unsafe fn uninit() -> Self { GetUsize { len: mem::size_of::<c_int>() as socklen_t, - val: mem::zeroed(), + val: MaybeUninit::uninit(), } } fn ffi_ptr(&mut self) -> *mut c_void { - &mut self.val as *mut c_int as *mut c_void + self.val.as_mut_ptr() as *mut c_void } fn ffi_len(&mut self) -> *mut socklen_t { &mut self.len } - unsafe fn unwrap(self) -> usize { + unsafe fn assume_init(self) -> usize { assert_eq!(self.len as usize, mem::size_of::<c_int>(), "invalid getsockopt implementation"); - self.val as usize + self.val.assume_init() as usize } } @@ -579,27 +582,29 @@ unsafe impl<'a> Set<'a, usize> for SetUsize { /// Getter for a `OsString` value. struct GetOsString<T: AsMut<[u8]>> { len: socklen_t, - val: T, + val: MaybeUninit<T>, } unsafe impl<T: AsMut<[u8]>> Get<OsString> for GetOsString<T> { - unsafe fn blank() -> Self { + unsafe fn uninit() -> Self { GetOsString { len: mem::size_of::<T>() as socklen_t, - val: mem::zeroed(), + val: MaybeUninit::uninit(), } } fn ffi_ptr(&mut self) -> *mut c_void { - &mut self.val as *mut T as *mut c_void + self.val.as_mut_ptr() as *mut c_void } fn ffi_len(&mut self) -> *mut socklen_t { &mut self.len } - unsafe fn unwrap(mut self) -> OsString { - OsStr::from_bytes(self.val.as_mut()).to_owned() + unsafe fn assume_init(self) -> OsString { + let len = self.len as usize; + let mut v = self.val.assume_init(); + OsStr::from_bytes(&v.as_mut()[0..len]).to_owned() } } |