diff --git a/src/libstd/process.rs b/src/libstd/process.rs index 52f5965db80..90eabaee77b 100644 --- a/src/libstd/process.rs +++ b/src/libstd/process.rs @@ -19,13 +19,13 @@ use io::prelude::*; use ffi::OsStr; use fmt; use io::{self, Error, ErrorKind}; -use libc; use path; use sync::mpsc::{channel, Receiver}; use sys::pipe2::{self, AnonPipe}; use sys::process2::Command as CommandImp; use sys::process2::Process as ProcessImp; use sys::process2::ExitStatus as ExitStatusImp; +use sys::process2::Stdio as StdioImp2; use sys_common::{AsInner, AsInnerMut}; use thread; @@ -229,13 +229,13 @@ impl Command { fn spawn_inner(&self, default_io: StdioImp) -> io::Result { let (their_stdin, our_stdin) = try!( - setup_io(self.stdin.as_ref().unwrap_or(&default_io), 0, true) + setup_io(self.stdin.as_ref().unwrap_or(&default_io), true) ); let (their_stdout, our_stdout) = try!( - setup_io(self.stdout.as_ref().unwrap_or(&default_io), 1, false) + setup_io(self.stdout.as_ref().unwrap_or(&default_io), false) ); let (their_stderr, our_stderr) = try!( - setup_io(self.stderr.as_ref().unwrap_or(&default_io), 2, false) + setup_io(self.stderr.as_ref().unwrap_or(&default_io), false) ); match ProcessImp::spawn(&self.inner, their_stdin, their_stdout, their_stderr) { @@ -328,23 +328,19 @@ impl AsInnerMut for Command { fn as_inner_mut(&mut self) -> &mut CommandImp { &mut self.inner } } -fn setup_io(io: &StdioImp, fd: libc::c_int, readable: bool) - -> io::Result<(Option, Option)> +fn setup_io(io: &StdioImp, readable: bool) + -> io::Result<(StdioImp2, Option)> { use self::StdioImp::*; Ok(match *io { - Null => { - (None, None) - } - Inherit => { - (Some(AnonPipe::from_fd(fd)), None) - } + Null => (StdioImp2::None, None), + Inherit => (StdioImp2::Inherit, None), Piped => { - let (reader, writer) = try!(unsafe { pipe2::anon_pipe() }); + let (reader, writer) = try!(pipe2::anon_pipe()); if readable { - (Some(reader), Some(writer)) + (StdioImp2::Piped(reader), Some(writer)) } else { - (Some(writer), Some(reader)) + (StdioImp2::Piped(writer), Some(reader)) } } }) diff --git a/src/libstd/sys/unix/c.rs b/src/libstd/sys/unix/c.rs index 5ae508e4610..aa4bf821207 100644 --- a/src/libstd/sys/unix/c.rs +++ b/src/libstd/sys/unix/c.rs @@ -26,39 +26,35 @@ use libc; target_os = "dragonfly", target_os = "bitrig", target_os = "openbsd"))] -pub const FIONBIO: libc::c_ulong = 0x8004667e; +mod consts { + use libc; + pub const FIONBIO: libc::c_ulong = 0x8004667e; + pub const FIOCLEX: libc::c_ulong = 0x20006601; + pub const FIONCLEX: libc::c_ulong = 0x20006602; +} #[cfg(any(all(target_os = "linux", any(target_arch = "x86", target_arch = "x86_64", target_arch = "arm", target_arch = "aarch64")), target_os = "android"))] -pub const FIONBIO: libc::c_ulong = 0x5421; +mod consts { + use libc; + pub const FIONBIO: libc::c_ulong = 0x5421; + pub const FIOCLEX: libc::c_ulong = 0x5451; + pub const FIONCLEX: libc::c_ulong = 0x5450; +} #[cfg(all(target_os = "linux", any(target_arch = "mips", target_arch = "mipsel", target_arch = "powerpc")))] -pub const FIONBIO: libc::c_ulong = 0x667e; - -#[cfg(any(target_os = "macos", - target_os = "ios", - target_os = "freebsd", - target_os = "dragonfly", - target_os = "bitrig", - target_os = "openbsd"))] -pub const FIOCLEX: libc::c_ulong = 0x20006601; -#[cfg(any(all(target_os = "linux", - any(target_arch = "x86", - target_arch = "x86_64", - target_arch = "arm", - target_arch = "aarch64")), - target_os = "android"))] -pub const FIOCLEX: libc::c_ulong = 0x5451; -#[cfg(all(target_os = "linux", - any(target_arch = "mips", - target_arch = "mipsel", - target_arch = "powerpc")))] -pub const FIOCLEX: libc::c_ulong = 0x6601; +mod consts { + use libc; + pub const FIONBIO: libc::c_ulong = 0x667e; + pub const FIOCLEX: libc::c_ulong = 0x6601; + pub const FIONCLEX: libc::c_ulong = 0x6600; +} +pub use self::consts::*; #[cfg(any(target_os = "macos", target_os = "ios", @@ -163,6 +159,8 @@ extern { pub fn utimes(filename: *const libc::c_char, times: *const libc::timeval) -> libc::c_int; pub fn gai_strerror(errcode: libc::c_int) -> *const libc::c_char; + pub fn setgroups(ngroups: libc::c_int, + ptr: *const libc::c_void) -> libc::c_int; } #[cfg(any(target_os = "macos", target_os = "ios"))] diff --git a/src/libstd/sys/unix/fd.rs b/src/libstd/sys/unix/fd.rs index f7c57c3f5e5..d86c77624e8 100644 --- a/src/libstd/sys/unix/fd.rs +++ b/src/libstd/sys/unix/fd.rs @@ -13,6 +13,7 @@ use core::prelude::*; use io; use libc::{self, c_int, size_t, c_void}; use mem; +use sys::c; use sys::cvt; use sys_common::AsInner; @@ -51,6 +52,13 @@ impl FileDesc { })); Ok(ret as usize) } + + pub fn set_cloexec(&self) { + unsafe { + let ret = c::ioctl(self.fd, c::FIOCLEX); + debug_assert_eq!(ret, 0); + } + } } impl AsInner for FileDesc { @@ -59,14 +67,11 @@ impl AsInner for FileDesc { impl Drop for FileDesc { fn drop(&mut self) { - // closing stdio file handles makes no sense, so never do it. Also, note - // that errors are ignored when closing a file descriptor. The reason - // for this is that if an error occurs we don't actually know if the - // file descriptor was closed or not, and if we retried (for something - // like EINTR), we might close another valid file descriptor (opened - // after we closed ours. - if self.fd > libc::STDERR_FILENO { - let _ = unsafe { libc::close(self.fd) }; - } + // Note that errors are ignored when closing a file descriptor. The + // reason for this is that if an error occurs we don't actually know if + // the file descriptor was closed or not, and if we retried (for + // something like EINTR), we might close another valid file descriptor + // (opened after we closed ours. + let _ = unsafe { libc::close(self.fd) }; } } diff --git a/src/libstd/sys/unix/fs2.rs b/src/libstd/sys/unix/fs2.rs index c0426af051b..ac121f1c82e 100644 --- a/src/libstd/sys/unix/fs2.rs +++ b/src/libstd/sys/unix/fs2.rs @@ -205,19 +205,27 @@ impl OpenOptions { impl File { pub fn open(path: &Path, opts: &OpenOptions) -> io::Result { + let path = try!(cstr(path)); + File::open_c(&path, opts) + } + + pub fn open_c(path: &CStr, opts: &OpenOptions) -> io::Result { let flags = opts.flags | match (opts.read, opts.write) { (true, true) => libc::O_RDWR, (false, true) => libc::O_WRONLY, (true, false) | (false, false) => libc::O_RDONLY, }; - let path = try!(cstr(path)); let fd = try!(cvt_r(|| unsafe { libc::open(path.as_ptr(), flags, opts.mode) })); - Ok(File(FileDesc::new(fd))) + let fd = FileDesc::new(fd); + fd.set_cloexec(); + Ok(File(fd)) } + pub fn into_fd(self) -> FileDesc { self.0 } + pub fn file_attr(&self) -> io::Result { let mut stat: libc::stat = unsafe { mem::zeroed() }; try!(cvt(unsafe { libc::fstat(self.0.raw(), &mut stat) })); diff --git a/src/libstd/sys/unix/net.rs b/src/libstd/sys/unix/net.rs index 908136a42ab..2e1cbb2a1e1 100644 --- a/src/libstd/sys/unix/net.rs +++ b/src/libstd/sys/unix/net.rs @@ -47,7 +47,9 @@ impl Socket { }; unsafe { let fd = try!(cvt(libc::socket(fam, ty, 0))); - Ok(Socket(FileDesc::new(fd))) + let fd = FileDesc::new(fd); + fd.set_cloexec(); + Ok(Socket(fd)) } } @@ -56,13 +58,16 @@ impl Socket { let fd = try!(cvt_r(|| unsafe { libc::accept(self.0.raw(), storage, len) })); - Ok(Socket(FileDesc::new(fd))) + let fd = FileDesc::new(fd); + fd.set_cloexec(); + Ok(Socket(fd)) } pub fn duplicate(&self) -> io::Result { - cvt(unsafe { libc::dup(self.0.raw()) }).map(|fd| { - Socket(FileDesc::new(fd)) - }) + let fd = try!(cvt(unsafe { libc::dup(self.0.raw()) })); + let fd = FileDesc::new(fd); + fd.set_cloexec(); + Ok(Socket(fd)) } pub fn read(&self, buf: &mut [u8]) -> io::Result { diff --git a/src/libstd/sys/unix/pipe2.rs b/src/libstd/sys/unix/pipe2.rs index 7af2c0f0b2a..e9d8c69fefb 100644 --- a/src/libstd/sys/unix/pipe2.rs +++ b/src/libstd/sys/unix/pipe2.rs @@ -20,11 +20,10 @@ use libc; pub struct AnonPipe(FileDesc); -pub unsafe fn anon_pipe() -> io::Result<(AnonPipe, AnonPipe)> { +pub fn anon_pipe() -> io::Result<(AnonPipe, AnonPipe)> { let mut fds = [0; 2]; - if libc::pipe(fds.as_mut_ptr()) == 0 { - Ok((AnonPipe::from_fd(fds[0]), - AnonPipe::from_fd(fds[1]))) + if unsafe { libc::pipe(fds.as_mut_ptr()) == 0 } { + Ok((AnonPipe::from_fd(fds[0]), AnonPipe::from_fd(fds[1]))) } else { Err(io::Error::last_os_error()) } @@ -32,7 +31,9 @@ pub unsafe fn anon_pipe() -> io::Result<(AnonPipe, AnonPipe)> { impl AnonPipe { pub fn from_fd(fd: libc::c_int) -> AnonPipe { - AnonPipe(FileDesc::new(fd)) + let fd = FileDesc::new(fd); + fd.set_cloexec(); + AnonPipe(fd) } pub fn read(&self, buf: &mut [u8]) -> io::Result { @@ -43,7 +44,7 @@ impl AnonPipe { self.0.write(buf) } - pub fn raw(&self) -> libc::c_int { - self.0.raw() + pub fn into_fd(self) -> FileDesc { + self.0 } } diff --git a/src/libstd/sys/unix/process2.rs b/src/libstd/sys/unix/process2.rs index 60f00c80b4a..0b4e871454d 100644 --- a/src/libstd/sys/unix/process2.rs +++ b/src/libstd/sys/unix/process2.rs @@ -13,14 +13,14 @@ use os::unix::prelude::*; use collections::HashMap; use env; -use ffi::{OsString, OsStr, CString}; +use ffi::{OsString, OsStr, CString, CStr}; use fmt; use io::{self, Error, ErrorKind}; use libc::{self, pid_t, c_void, c_int, gid_t, uid_t}; -use mem; use ptr; use sys::pipe2::AnonPipe; use sys::{self, retry, c, cvt}; +use sys::fs2::{File, OpenOptions}; //////////////////////////////////////////////////////////////////////////////// // Command @@ -119,6 +119,12 @@ pub struct Process { pid: pid_t } +pub enum Stdio { + Inherit, + Piped(AnonPipe), + None, +} + const CLOEXEC_MSG_FOOTER: &'static [u8] = b"NOEX"; impl Process { @@ -128,221 +134,185 @@ impl Process { } pub fn spawn(cfg: &Command, - in_fd: Option, out_fd: Option, err_fd: Option) - -> io::Result - { - use libc::funcs::posix88::unistd::{fork, dup2, close, chdir, execvp}; + in_fd: Stdio, + out_fd: Stdio, + err_fd: Stdio) -> io::Result { + let dirp = cfg.cwd.as_ref().map(|c| c.as_ptr()).unwrap_or(ptr::null()); - mod rustrt { - extern { - pub fn rust_unset_sigprocmask(); + let (envp, _a, _b) = make_envp(cfg.env.as_ref()); + let (argv, _a) = make_argv(&cfg.program, &cfg.args); + let (input, output) = try!(sys::pipe2::anon_pipe()); + + let pid = unsafe { + match libc::fork() { + 0 => { + drop(input); + Process::child_after_fork(cfg, output, argv, envp, dirp, + in_fd, out_fd, err_fd) + } + n if n < 0 => return Err(Error::last_os_error()), + n => n, + } + }; + + let p = Process{ pid: pid }; + drop(output); + let mut bytes = [0; 8]; + + // loop to handle EINTR + loop { + match input.read(&mut bytes) { + Ok(0) => return Ok(p), + Ok(8) => { + assert!(combine(CLOEXEC_MSG_FOOTER) == combine(&bytes[4.. 8]), + "Validation on the CLOEXEC pipe failed: {:?}", bytes); + let errno = combine(&bytes[0.. 4]); + assert!(p.wait().is_ok(), + "wait() should either return Ok or panic"); + return Err(Error::from_raw_os_error(errno)) + } + Err(ref e) if e.kind() == ErrorKind::Interrupted => {} + Err(e) => { + assert!(p.wait().is_ok(), + "wait() should either return Ok or panic"); + panic!("the CLOEXEC pipe failed: {:?}", e) + }, + Ok(..) => { // pipe I/O up to PIPE_BUF bytes should be atomic + assert!(p.wait().is_ok(), + "wait() should either return Ok or panic"); + panic!("short read on the CLOEXEC pipe") + } } } - unsafe fn set_cloexec(fd: c_int) { - let ret = c::ioctl(fd, c::FIOCLEX); - assert_eq!(ret, 0); + fn combine(arr: &[u8]) -> i32 { + let a = arr[0] as u32; + let b = arr[1] as u32; + let c = arr[2] as u32; + let d = arr[3] as u32; + + ((a << 24) | (b << 16) | (c << 8) | (d << 0)) as i32 + } + } + + // And at this point we've reached a special time in the life of the + // child. The child must now be considered hamstrung and unable to + // do anything other than syscalls really. Consider the following + // scenario: + // + // 1. Thread A of process 1 grabs the malloc() mutex + // 2. Thread B of process 1 forks(), creating thread C + // 3. Thread C of process 2 then attempts to malloc() + // 4. The memory of process 2 is the same as the memory of + // process 1, so the mutex is locked. + // + // This situation looks a lot like deadlock, right? It turns out + // that this is what pthread_atfork() takes care of, which is + // presumably implemented across platforms. The first thing that + // threads to *before* forking is to do things like grab the malloc + // mutex, and then after the fork they unlock it. + // + // Despite this information, libnative's spawn has been witnessed to + // deadlock on both OSX and FreeBSD. I'm not entirely sure why, but + // all collected backtraces point at malloc/free traffic in the + // child spawned process. + // + // For this reason, the block of code below should contain 0 + // invocations of either malloc of free (or their related friends). + // + // As an example of not having malloc/free traffic, we don't close + // this file descriptor by dropping the FileDesc (which contains an + // allocation). Instead we just close it manually. This will never + // have the drop glue anyway because this code never returns (the + // child will either exec() or invoke libc::exit) + unsafe fn child_after_fork(cfg: &Command, + mut output: AnonPipe, + argv: *const *const libc::c_char, + envp: *const libc::c_void, + dirp: *const libc::c_char, + in_fd: Stdio, + out_fd: Stdio, + err_fd: Stdio) -> ! { + fn fail(output: &mut AnonPipe) -> ! { + let errno = sys::os::errno() as u32; + let bytes = [ + (errno >> 24) as u8, + (errno >> 16) as u8, + (errno >> 8) as u8, + (errno >> 0) as u8, + CLOEXEC_MSG_FOOTER[0], CLOEXEC_MSG_FOOTER[1], + CLOEXEC_MSG_FOOTER[2], CLOEXEC_MSG_FOOTER[3] + ]; + // pipe I/O up to PIPE_BUF bytes should be atomic, and then we want + // to be sure we *don't* run at_exit destructors as we're being torn + // down regardless + assert!(output.write(&bytes).is_ok()); + unsafe { libc::_exit(1) } } - #[cfg(all(target_os = "android", target_arch = "aarch64"))] - unsafe fn getdtablesize() -> c_int { - libc::sysconf(libc::consts::os::sysconf::_SC_OPEN_MAX) as c_int - } + let setup = |src: Stdio, dst: c_int| { + let fd = match src { + Stdio::Inherit => return true, + Stdio::Piped(pipe) => pipe.into_fd(), - #[cfg(not(all(target_os = "android", target_arch = "aarch64")))] - unsafe fn getdtablesize() -> c_int { - libc::funcs::bsd44::getdtablesize() - } - - let dirp = cfg.cwd.as_ref().map(|c| c.as_ptr()).unwrap_or(ptr::null()); - - with_envp(cfg.env.as_ref(), |envp: *const c_void| { - with_argv(&cfg.program, &cfg.args, |argv: *const *const libc::c_char| unsafe { - let (input, mut output) = try!(sys::pipe2::anon_pipe()); - - // We may use this in the child, so perform allocations before the - // fork - let devnull = b"/dev/null\0"; - - set_cloexec(output.raw()); - - let pid = fork(); - if pid < 0 { - return Err(Error::last_os_error()) - } else if pid > 0 { - #[inline] - fn combine(arr: &[u8]) -> i32 { - let a = arr[0] as u32; - let b = arr[1] as u32; - let c = arr[2] as u32; - let d = arr[3] as u32; - - ((a << 24) | (b << 16) | (c << 8) | (d << 0)) as i32 - } - - let p = Process{ pid: pid }; - drop(output); - let mut bytes = [0; 8]; - - // loop to handle EINTER - loop { - match input.read(&mut bytes) { - Ok(8) => { - assert!(combine(CLOEXEC_MSG_FOOTER) == combine(&bytes[4.. 8]), - "Validation on the CLOEXEC pipe failed: {:?}", bytes); - let errno = combine(&bytes[0.. 4]); - assert!(p.wait().is_ok(), - "wait() should either return Ok or panic"); - return Err(Error::from_raw_os_error(errno)) - } - Ok(0) => return Ok(p), - Err(ref e) if e.kind() == ErrorKind::Interrupted => {} - Err(e) => { - assert!(p.wait().is_ok(), - "wait() should either return Ok or panic"); - panic!("the CLOEXEC pipe failed: {:?}", e) - }, - Ok(..) => { // pipe I/O up to PIPE_BUF bytes should be atomic - assert!(p.wait().is_ok(), - "wait() should either return Ok or panic"); - panic!("short read on the CLOEXEC pipe") - } - } + // If a stdio file descriptor is set to be ignored, we open up + // /dev/null into that file descriptor. Otherwise, the first + // file descriptor opened up in the child would be numbered as + // one of the stdio file descriptors, which is likely to wreak + // havoc. + Stdio::None => { + let mut opts = OpenOptions::new(); + opts.read(dst == libc::STDIN_FILENO); + opts.write(dst != libc::STDIN_FILENO); + let devnull = CStr::from_ptr(b"/dev/null\0".as_ptr() + as *const _); + if let Ok(f) = File::open_c(devnull, &opts) { + f.into_fd() + } else { + return false } } + }; + retry(|| libc::dup2(fd.raw(), dst)) != -1 + }; - // And at this point we've reached a special time in the life of the - // child. The child must now be considered hamstrung and unable to - // do anything other than syscalls really. Consider the following - // scenario: - // - // 1. Thread A of process 1 grabs the malloc() mutex - // 2. Thread B of process 1 forks(), creating thread C - // 3. Thread C of process 2 then attempts to malloc() - // 4. The memory of process 2 is the same as the memory of - // process 1, so the mutex is locked. - // - // This situation looks a lot like deadlock, right? It turns out - // that this is what pthread_atfork() takes care of, which is - // presumably implemented across platforms. The first thing that - // threads to *before* forking is to do things like grab the malloc - // mutex, and then after the fork they unlock it. - // - // Despite this information, libnative's spawn has been witnessed to - // deadlock on both OSX and FreeBSD. I'm not entirely sure why, but - // all collected backtraces point at malloc/free traffic in the - // child spawned process. - // - // For this reason, the block of code below should contain 0 - // invocations of either malloc of free (or their related friends). - // - // As an example of not having malloc/free traffic, we don't close - // this file descriptor by dropping the FileDesc (which contains an - // allocation). Instead we just close it manually. This will never - // have the drop glue anyway because this code never returns (the - // child will either exec() or invoke libc::exit) - let _ = libc::close(input.raw()); + if !setup(in_fd, libc::STDIN_FILENO) { fail(&mut output) } + if !setup(out_fd, libc::STDOUT_FILENO) { fail(&mut output) } + if !setup(err_fd, libc::STDERR_FILENO) { fail(&mut output) } - fn fail(output: &mut AnonPipe) -> ! { - let errno = sys::os::errno() as u32; - let bytes = [ - (errno >> 24) as u8, - (errno >> 16) as u8, - (errno >> 8) as u8, - (errno >> 0) as u8, - CLOEXEC_MSG_FOOTER[0], CLOEXEC_MSG_FOOTER[1], - CLOEXEC_MSG_FOOTER[2], CLOEXEC_MSG_FOOTER[3] - ]; - // pipe I/O up to PIPE_BUF bytes should be atomic - assert!(output.write(&bytes).is_ok()); - unsafe { libc::_exit(1) } - } - - rustrt::rust_unset_sigprocmask(); - - // If a stdio file descriptor is set to be ignored, we don't - // actually close it, but rather open up /dev/null into that - // file descriptor. Otherwise, the first file descriptor opened - // up in the child would be numbered as one of the stdio file - // descriptors, which is likely to wreak havoc. - let setup = |src: Option, dst: c_int| { - let src = match src { - None => { - let flags = if dst == libc::STDIN_FILENO { - libc::O_RDONLY - } else { - libc::O_RDWR - }; - libc::open(devnull.as_ptr() as *const _, flags, 0) - } - Some(obj) => { - let fd = obj.raw(); - // Leak the memory and the file descriptor. We're in the - // child now an all our resources are going to be - // cleaned up very soon - mem::forget(obj); - fd - } - }; - src != -1 && retry(|| dup2(src, dst)) != -1 - }; - - if !setup(in_fd, libc::STDIN_FILENO) { fail(&mut output) } - if !setup(out_fd, libc::STDOUT_FILENO) { fail(&mut output) } - if !setup(err_fd, libc::STDERR_FILENO) { fail(&mut output) } - - // close all other fds - for fd in (3..getdtablesize()).rev() { - if fd != output.raw() { - let _ = close(fd as c_int); - } - } - - match cfg.gid { - Some(u) => { - if libc::setgid(u as libc::gid_t) != 0 { - fail(&mut output); - } - } - None => {} - } - match cfg.uid { - Some(u) => { - // When dropping privileges from root, the `setgroups` call - // will remove any extraneous groups. If we don't call this, - // then even though our uid has dropped, we may still have - // groups that enable us to do super-user things. This will - // fail if we aren't root, so don't bother checking the - // return value, this is just done as an optimistic - // privilege dropping function. - extern { - fn setgroups(ngroups: libc::c_int, - ptr: *const libc::c_void) -> libc::c_int; - } - let _ = setgroups(0, ptr::null()); - - if libc::setuid(u as libc::uid_t) != 0 { - fail(&mut output); - } - } - None => {} - } - if cfg.detach { - // Don't check the error of setsid because it fails if we're the - // process leader already. We just forked so it shouldn't return - // error, but ignore it anyway. - let _ = libc::setsid(); - } - if !dirp.is_null() && chdir(dirp) == -1 { - fail(&mut output); - } - if !envp.is_null() { - *sys::os::environ() = envp as *const _; - } - let _ = execvp(*argv, argv as *mut _); + if let Some(u) = cfg.gid { + if libc::setgid(u as libc::gid_t) != 0 { fail(&mut output); - }) - }) + } + } + if let Some(u) = cfg.uid { + // When dropping privileges from root, the `setgroups` call + // will remove any extraneous groups. If we don't call this, + // then even though our uid has dropped, we may still have + // groups that enable us to do super-user things. This will + // fail if we aren't root, so don't bother checking the + // return value, this is just done as an optimistic + // privilege dropping function. + let _ = c::setgroups(0, ptr::null()); + + if libc::setuid(u as libc::uid_t) != 0 { + fail(&mut output); + } + } + if cfg.detach { + // Don't check the error of setsid because it fails if we're the + // process leader already. We just forked so it shouldn't return + // error, but ignore it anyway. + let _ = libc::setsid(); + } + if !dirp.is_null() && libc::chdir(dirp) == -1 { + fail(&mut output); + } + if !envp.is_null() { + *sys::os::environ() = envp as *const _; + } + let _ = libc::execvp(*argv, argv as *mut _); + fail(&mut output) } pub fn wait(&self) -> io::Result { @@ -364,8 +334,8 @@ impl Process { } } -fn with_argv(prog: &CString, args: &[CString], cb: F) -> T - where F : FnOnce(*const *const libc::c_char) -> T +fn make_argv(prog: &CString, args: &[CString]) + -> (*const *const libc::c_char, Vec<*const libc::c_char>) { let mut ptrs: Vec<*const libc::c_char> = Vec::with_capacity(args.len()+1); @@ -380,40 +350,38 @@ fn with_argv(prog: &CString, args: &[CString], cb: F) -> T // Add a terminating null pointer (required by libc). ptrs.push(ptr::null()); - cb(ptrs.as_ptr()) + (ptrs.as_ptr(), ptrs) } -fn with_envp(env: Option<&HashMap>, cb: F) -> T - where F : FnOnce(*const c_void) -> T +fn make_envp(env: Option<&HashMap>) + -> (*const c_void, Vec>, Vec<*const libc::c_char>) { // On posixy systems we can pass a char** for envp, which is a // null-terminated array of "k=v\0" strings. Since we must create // these strings locally, yet expose a raw pointer to them, we // create a temporary vector to own the CStrings that outlives the // call to cb. - match env { - Some(env) => { - let mut tmps = Vec::with_capacity(env.len()); + if let Some(env) = env { + let mut tmps = Vec::with_capacity(env.len()); - for pair in env { - let mut kv = Vec::new(); - kv.push_all(pair.0.as_bytes()); - kv.push('=' as u8); - kv.push_all(pair.1.as_bytes()); - kv.push(0); // terminating null - tmps.push(kv); - } - - // As with `with_argv`, this is unsafe, since cb could leak the pointers. - let mut ptrs: Vec<*const libc::c_char> = - tmps.iter() - .map(|tmp| tmp.as_ptr() as *const libc::c_char) - .collect(); - ptrs.push(ptr::null()); - - cb(ptrs.as_ptr() as *const c_void) + for pair in env { + let mut kv = Vec::new(); + kv.push_all(pair.0.as_bytes()); + kv.push('=' as u8); + kv.push_all(pair.1.as_bytes()); + kv.push(0); // terminating null + tmps.push(kv); } - _ => cb(ptr::null()) + + let mut ptrs: Vec<*const libc::c_char> = + tmps.iter() + .map(|tmp| tmp.as_ptr() as *const libc::c_char) + .collect(); + ptrs.push(ptr::null()); + + (ptrs.as_ptr() as *const _, tmps, ptrs) + } else { + (0 as *const _, Vec::new(), Vec::new()) } } diff --git a/src/libstd/sys/windows/pipe2.rs b/src/libstd/sys/windows/pipe2.rs index 229481e3d57..ed41c959782 100644 --- a/src/libstd/sys/windows/pipe2.rs +++ b/src/libstd/sys/windows/pipe2.rs @@ -22,22 +22,24 @@ pub struct AnonPipe { fd: c_int } -pub unsafe fn anon_pipe() -> io::Result<(AnonPipe, AnonPipe)> { +pub fn anon_pipe() -> io::Result<(AnonPipe, AnonPipe)> { // Windows pipes work subtly differently than unix pipes, and their // inheritance has to be handled in a different way that I do not // fully understand. Here we explicitly make the pipe non-inheritable, // which means to pass it to a subprocess they need to be duplicated // first, as in std::run. let mut fds = [0; 2]; - match libc::pipe(fds.as_mut_ptr(), 1024 as ::libc::c_uint, - (libc::O_BINARY | libc::O_NOINHERIT) as c_int) { - 0 => { - assert!(fds[0] != -1 && fds[0] != 0); - assert!(fds[1] != -1 && fds[1] != 0); + unsafe { + match libc::pipe(fds.as_mut_ptr(), 1024 as ::libc::c_uint, + (libc::O_BINARY | libc::O_NOINHERIT) as c_int) { + 0 => { + assert!(fds[0] != -1 && fds[0] != 0); + assert!(fds[1] != -1 && fds[1] != 0); - Ok((AnonPipe::from_fd(fds[0]), AnonPipe::from_fd(fds[1]))) + Ok((AnonPipe::from_fd(fds[0]), AnonPipe::from_fd(fds[1]))) + } + _ => Err(io::Error::last_os_error()), } - _ => Err(io::Error::last_os_error()), } } diff --git a/src/libstd/sys/windows/process2.rs b/src/libstd/sys/windows/process2.rs index 7e832b6384d..74953921921 100644 --- a/src/libstd/sys/windows/process2.rs +++ b/src/libstd/sys/windows/process2.rs @@ -105,11 +105,18 @@ pub struct Process { handle: Handle, } +pub enum Stdio { + Inherit, + Piped(AnonPipe), + None, +} + impl Process { #[allow(deprecated)] pub fn spawn(cfg: &Command, - in_fd: Option, out_fd: Option, err_fd: Option) - -> io::Result + in_fd: Stdio, + out_fd: Stdio, + err_fd: Stdio) -> io::Result { use libc::types::os::arch::extra::{DWORD, HANDLE, STARTUPINFO}; use libc::consts::os::extra::{ @@ -156,13 +163,16 @@ impl Process { let cur_proc = GetCurrentProcess(); - // Similarly to unix, we don't actually leave holes for the stdio file - // descriptors, but rather open up /dev/null equivalents. These - // equivalents are drawn from libuv's windows process spawning. - let set_fd = |fd: &Option, slot: &mut HANDLE, + let set_fd = |fd: &Stdio, slot: &mut HANDLE, is_stdin: bool| { match *fd { - None => { + Stdio::Inherit => {} + + // Similarly to unix, we don't actually leave holes for the + // stdio file descriptors, but rather open up /dev/null + // equivalents. These equivalents are drawn from libuv's + // windows process spawning. + Stdio::None => { let access = if is_stdin { libc::FILE_GENERIC_READ } else { @@ -188,11 +198,8 @@ impl Process { return Err(Error::last_os_error()) } } - Some(ref pipe) => { + Stdio::Piped(ref pipe) => { let orig = pipe.raw(); - if orig == INVALID_HANDLE_VALUE { - return Err(Error::last_os_error()) - } if DuplicateHandle(cur_proc, orig, cur_proc, slot, 0, TRUE, DUPLICATE_SAME_ACCESS) == FALSE { return Err(Error::last_os_error()) @@ -235,9 +242,15 @@ impl Process { }) }); - assert!(CloseHandle(si.hStdInput) != 0); - assert!(CloseHandle(si.hStdOutput) != 0); - assert!(CloseHandle(si.hStdError) != 0); + if !in_fd.inherited() { + assert!(CloseHandle(si.hStdInput) != 0); + } + if !out_fd.inherited() { + assert!(CloseHandle(si.hStdOutput) != 0); + } + if !err_fd.inherited() { + assert!(CloseHandle(si.hStdError) != 0); + } match create_err { Some(err) => return Err(err), @@ -296,6 +309,12 @@ impl Process { } } +impl Stdio { + fn inherited(&self) -> bool { + match *self { Stdio::Inherit => true, _ => false } + } +} + #[derive(PartialEq, Eq, Clone, Copy, Debug)] pub struct ExitStatus(i32); diff --git a/src/test/run-pass/fds-are-cloexec.rs b/src/test/run-pass/fds-are-cloexec.rs new file mode 100644 index 00000000000..cbf7830513a --- /dev/null +++ b/src/test/run-pass/fds-are-cloexec.rs @@ -0,0 +1,76 @@ +// Copyright 2015 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +// ignore-windows +// ignore-android + +#![feature(libc)] + +extern crate libc; + +use std::env; +use std::fs::{self, File}; +use std::io; +use std::net::{TcpListener, TcpStream, UdpSocket}; +use std::os::unix::prelude::*; +use std::process::Command; +use std::thread; + +fn main() { + let args = env::args().collect::>(); + if args.len() == 1 { + parent() + } else { + child(&args) + } +} + +fn parent() { + let file = File::open("Makefile").unwrap(); + let _dir = fs::read_dir("/").unwrap(); + let tcp1 = TcpListener::bind("127.0.0.1:0").unwrap(); + assert_eq!(tcp1.as_raw_fd(), file.as_raw_fd() + 2); + let tcp2 = tcp1.try_clone().unwrap(); + let addr = tcp1.local_addr().unwrap(); + let t = thread::scoped(|| TcpStream::connect(addr).unwrap()); + let tcp3 = tcp1.accept().unwrap().0; + let tcp4 = t.join(); + let tcp5 = tcp3.try_clone().unwrap(); + let tcp6 = tcp4.try_clone().unwrap(); + let udp1 = UdpSocket::bind("127.0.0.1:0").unwrap(); + let udp2 = udp1.try_clone().unwrap(); + + let status = Command::new(env::args().next().unwrap()) + .arg(file.as_raw_fd().to_string()) + .arg((file.as_raw_fd() + 1).to_string()) + .arg(tcp1.as_raw_fd().to_string()) + .arg(tcp2.as_raw_fd().to_string()) + .arg(tcp3.as_raw_fd().to_string()) + .arg(tcp4.as_raw_fd().to_string()) + .arg(tcp5.as_raw_fd().to_string()) + .arg(tcp6.as_raw_fd().to_string()) + .arg(udp1.as_raw_fd().to_string()) + .arg(udp2.as_raw_fd().to_string()) + .status() + .unwrap(); + assert!(status.success()); +} + +fn child(args: &[String]) { + let mut b = [0u8; 2]; + for arg in &args[1..] { + let fd: libc::c_int = arg.parse().unwrap(); + unsafe { + assert_eq!(libc::read(fd, b.as_mut_ptr() as *mut _, 2), -1); + assert_eq!(io::Error::last_os_error().raw_os_error(), + Some(libc::EBADF)); + } + } +}