std: Properly handle interior NULs in std::process

src/libstd/process.rs

@@ -343,11 +343,7 @@ impl fmt::Debug for Command {
  /// non-utf8 data is lossily converted using the utf8 replacement
  /// character.
  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- try!(write!(f, "{:?}", self.inner.program));
- for arg in &self.inner.args {
- try!(write!(f, " {:?}", arg));
- }
- Ok(())
+ self.inner.fmt(f)
  }
 }
 
@@ -877,4 +873,54 @@ mod tests {
  assert!(output.contains("RUN_TEST_NEW_ENV=123"),
  "didn't find RUN_TEST_NEW_ENV inside of:\n\n{}", output);
  }
+
+ // Regression tests for #30858.
+ #[test]
+ fn test_interior_nul_in_progname_is_error() {
+ match Command::new("has-some-\0\0s-inside").spawn() {
+ Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),
+ Ok(_) => panic!(),
+ }
+ }
+
+ #[test]
+ fn test_interior_nul_in_arg_is_error() {
+ match Command::new("echo").arg("has-some-\0\0s-inside").spawn() {
+ Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),
+ Ok(_) => panic!(),
+ }
+ }
+
+ #[test]
+ fn test_interior_nul_in_args_is_error() {
+ match Command::new("echo").args(&["has-some-\0\0s-inside"]).spawn() {
+ Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),
+ Ok(_) => panic!(),
+ }
+ }
+
+ #[test]
+ fn test_interior_nul_in_current_dir_is_error() {
+ match Command::new("echo").current_dir("has-some-\0\0s-inside").spawn() {
+ Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),
+ Ok(_) => panic!(),
+ }
+ }
+
+ // Regression tests for #30862.
+ #[test]
+ fn test_interior_nul_in_env_key_is_error() {
+ match env_cmd().env("has-some-\0\0s-inside", "value").spawn() {
+ Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),
+ Ok(_) => panic!(),
+ }
+ }
+
+ #[test]
+ fn test_interior_nul_in_env_value_is_error() {
+ match env_cmd().env("key", "has-some-\0\0s-inside").spawn() {
+ Err(e) => assert_eq!(e.kind(), ErrorKind::InvalidInput),
+ Ok(_) => panic!(),
+ }
+ }
 }

src/libstd/sys/unix/ext/process.rs

@@ -49,17 +49,17 @@ pub trait CommandExt {
 #[stable(feature = "rust1", since = "1.0.0")]
 impl CommandExt for process::Command {
  fn uid(&mut self, id: uid_t) -> &mut process::Command {
- self.as_inner_mut().uid = Some(id);
+ self.as_inner_mut().uid(id);
  self
  }
 
  fn gid(&mut self, id: gid_t) -> &mut process::Command {
- self.as_inner_mut().gid = Some(id);
+ self.as_inner_mut().gid(id);
  self
  }
 
  fn session_leader(&mut self, on: bool) -> &mut process::Command {
- self.as_inner_mut().session_leader = on;
+ self.as_inner_mut().session_leader(on);
  self
  }
 }

src/libstd/sys/unix/process.rs

@@ -31,57 +31,95 @@ use sys::{self, cvt, cvt_r};
 
 #[derive(Clone)]
 pub struct Command {
- pub program: CString,
- pub args: Vec<CString>,
- pub env: Option<HashMap<OsString, OsString>>,
- pub cwd: Option<CString>,
- pub uid: Option<uid_t>,
- pub gid: Option<gid_t>,
- pub session_leader: bool,
+ program: CString,
+ args: Vec<CString>,
+ env: Option<HashMap<OsString, OsString>>, // Guaranteed to have no NULs.
+ cwd: Option<CString>,
+ uid: Option<uid_t>,
+ gid: Option<gid_t>,
+ session_leader: bool,
+ saw_nul: bool,
 }
 
 impl Command {
  pub fn new(program: &OsStr) -> Command {
+ let mut saw_nul = false;
  Command {
- program: os2c(program),
+ program: os2c(program, &mut saw_nul),
  args: Vec::new(),
  env: None,
  cwd: None,
  uid: None,
  gid: None,
  session_leader: false,
+ saw_nul: saw_nul,
  }
  }
 
  pub fn arg(&mut self, arg: &OsStr) {
- self.args.push(os2c(arg));
+ self.args.push(os2c(arg, &mut self.saw_nul));
  }
  pub fn args<'a, I: Iterator<Item = &'a OsStr>>(&mut self, args: I) {
- self.args.extend(args.map(os2c));
+ let mut saw_nul = self.saw_nul;
+ self.args.extend(args.map(|arg| os2c(arg, &mut saw_nul)));
+ self.saw_nul = saw_nul;
  }
  fn init_env_map(&mut self) {
  if self.env.is_none() {
+ // Will not add NULs to env: preexisting environment will not contain any.
  self.env = Some(env::vars_os().collect());
  }
  }
  pub fn env(&mut self, key: &OsStr, val: &OsStr) {
+ let k = OsString::from_vec(os2c(key, &mut self.saw_nul).into_bytes());
+ let v = OsString::from_vec(os2c(val, &mut self.saw_nul).into_bytes());
+
+ // Will not add NULs to env: return without inserting if any were seen.
+ if self.saw_nul {
+ return;
+ }
+
  self.init_env_map();
- self.env.as_mut().unwrap().insert(key.to_os_string(), val.to_os_string());
+ self.env.as_mut()
+ .unwrap()
+ .insert(k, v);
  }
  pub fn env_remove(&mut self, key: &OsStr) {
  self.init_env_map();
- self.env.as_mut().unwrap().remove(&key.to_os_string());
+ self.env.as_mut().unwrap().remove(key);
  }
  pub fn env_clear(&mut self) {
  self.env = Some(HashMap::new())
  }
  pub fn cwd(&mut self, dir: &OsStr) {
- self.cwd = Some(os2c(dir));
+ self.cwd = Some(os2c(dir, &mut self.saw_nul));
+ }
+ pub fn uid(&mut self, id: uid_t) {
+ self.uid = Some(id);
  }
+ pub fn gid(&mut self, id: gid_t) {
+ self.gid = Some(id);
+ }
+ pub fn session_leader(&mut self, session_leader: bool) {
+ self.session_leader = session_leader;
+ }
+}
+
+fn os2c(s: &OsStr, saw_nul: &mut bool) -> CString {
+ CString::new(s.as_bytes()).unwrap_or_else(|_e| {
+ *saw_nul = true;
+ CString::new("<string-with-nul>").unwrap()
+ })
 }
 
-fn os2c(s: &OsStr) -> CString {
- CString::new(s.as_bytes()).unwrap()
+impl fmt::Debug for Command {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ try!(write!(f, "{:?}", self.program));
+ for arg in &self.args {
+ try!(write!(f, " {:?}", arg));
+ }
+ Ok(())
+ }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -175,6 +213,10 @@ impl Process {
  in_fd: Stdio,
  out_fd: Stdio,
  err_fd: Stdio) -> io::Result<Process> {
+ if cfg.saw_nul {
+ return Err(io::Error::new(ErrorKind::InvalidInput, "nul byte found in provided data"));
+ }
+
  let dirp = cfg.cwd.as_ref().map(|c| c.as_ptr()).unwrap_or(ptr::null());
 
  let (envp, _a, _b) = make_envp(cfg.env.as_ref());

src/libstd/sys/windows/process.rs

@@ -18,7 +18,7 @@ use env;
 use ffi::{OsString, OsStr};
 use fmt;
 use fs;
-use io::{self, Error};
+use io::{self, Error, ErrorKind};
 use libc::c_void;
 use mem;
 use os::windows::ffi::OsStrExt;
@@ -43,13 +43,21 @@ fn mk_key(s: &OsStr) -> OsString {
  })
 }
 
+fn ensure_no_nuls<T: AsRef<OsStr>>(str: T) -> io::Result<T> {
+ if str.as_ref().encode_wide().any(|b| b == 0) {
+ Err(io::Error::new(ErrorKind::InvalidInput, "nul byte found in provided data"))
+ } else {
+ Ok(str)
+ }
+}
+
 #[derive(Clone)]
 pub struct Command {
- pub program: OsString,
- pub args: Vec<OsString>,
- pub env: Option<HashMap<OsString, OsString>>,
- pub cwd: Option<OsString>,
- pub detach: bool, // not currently exposed in std::process
+ program: OsString,
+ args: Vec<OsString>,
+ env: Option<HashMap<OsString, OsString>>,
+ cwd: Option<OsString>,
+ detach: bool, // not currently exposed in std::process
 }
 
 impl Command {
@@ -92,6 +100,16 @@ impl Command {
  }
 }
 
+impl fmt::Debug for Command {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ try!(write!(f, "{:?}", self.program));
+ for arg in &self.args {
+ try!(write!(f, " {:?}", arg));
+ }
+ Ok(())
+ }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Processes
 ////////////////////////////////////////////////////////////////////////////////
@@ -153,7 +171,7 @@ impl Process {
  si.hStdError = stderr.raw();
 
  let program = program.as_ref().unwrap_or(&cfg.program);
- let mut cmd_str = make_command_line(program, &cfg.args);
+ let mut cmd_str = try!(make_command_line(program, &cfg.args));
  cmd_str.push(0); // add null terminator
 
  // stolen from the libuv code.
@@ -162,8 +180,8 @@ impl Process {
  flags |= c::DETACHED_PROCESS | c::CREATE_NEW_PROCESS_GROUP;
  }
 
- let (envp, _data) = make_envp(cfg.env.as_ref());
- let (dirp, _data) = make_dirp(cfg.cwd.as_ref());
+ let (envp, _data) = try!(make_envp(cfg.env.as_ref()));
+ let (dirp, _data) = try!(make_dirp(cfg.cwd.as_ref()));
  let mut pi = zeroed_process_information();
  try!(unsafe {
  // `CreateProcess` is racy!
@@ -265,22 +283,24 @@ fn zeroed_process_information() -> c::PROCESS_INFORMATION {
  }
 }
 
-// Produces a wide string *without terminating null*
-fn make_command_line(prog: &OsStr, args: &[OsString]) -> Vec<u16> {
+// Produces a wide string *without terminating null*; returns an error if
+// `prog` or any of the `args` contain a nul.
+fn make_command_line(prog: &OsStr, args: &[OsString]) -> io::Result<Vec<u16>> {
  // Encode the command and arguments in a command line string such
  // that the spawned process may recover them using CommandLineToArgvW.
  let mut cmd: Vec<u16> = Vec::new();
- append_arg(&mut cmd, prog);
+ try!(append_arg(&mut cmd, prog));
  for arg in args {
  cmd.push(' ' as u16);
- append_arg(&mut cmd, arg);
+ try!(append_arg(&mut cmd, arg));
  }
- return cmd;
+ return Ok(cmd);
 
- fn append_arg(cmd: &mut Vec<u16>, arg: &OsStr) {
+ fn append_arg(cmd: &mut Vec<u16>, arg: &OsStr) -> io::Result<()> {
  // If an argument has 0 characters then we need to quote it to ensure
  // that it actually gets passed through on the command line or otherwise
  // it will be dropped entirely when parsed on the other end.
+ try!(ensure_no_nuls(arg));
  let arg_bytes = &arg.as_inner().inner.as_inner();
  let quote = arg_bytes.iter().any(|c| *c == b' ' || *c == b'\t')
  || arg_bytes.is_empty();
@@ -312,11 +332,12 @@ fn make_command_line(prog: &OsStr, args: &[OsString]) -> Vec<u16> {
  }
  cmd.push('"' as u16);
  }
+ Ok(())
  }
 }
 
 fn make_envp(env: Option<&collections::HashMap<OsString, OsString>>)
- -> (*mut c_void, Vec<u16>) {
+ -> io::Result<(*mut c_void, Vec<u16>)> {
  // On Windows we pass an "environment block" which is not a char**, but
  // rather a concatenation of null-terminated k=v\0 sequences, with a final
  // \0 to terminate.
@@ -325,26 +346,27 @@ fn make_envp(env: Option<&collections::HashMap<OsString, OsString>>)
  let mut blk = Vec::new();
 
  for pair in env {
- blk.extend(pair.0.encode_wide());
+ blk.extend(try!(ensure_no_nuls(pair.0)).encode_wide());
  blk.push('=' as u16);
- blk.extend(pair.1.encode_wide());
+ blk.extend(try!(ensure_no_nuls(pair.1)).encode_wide());
  blk.push(0);
  }
  blk.push(0);
- (blk.as_mut_ptr() as *mut c_void, blk)
+ Ok((blk.as_mut_ptr() as *mut c_void, blk))
  }
- _ => (ptr::null_mut(), Vec::new())
+ _ => Ok((ptr::null_mut(), Vec::new()))
  }
 }
 
-fn make_dirp(d: Option<&OsString>) -> (*const u16, Vec<u16>) {
+fn make_dirp(d: Option<&OsString>) -> io::Result<(*const u16, Vec<u16>)> {
+
  match d {
  Some(dir) => {
- let mut dir_str: Vec<u16> = dir.encode_wide().collect();
+ let mut dir_str: Vec<u16> = try!(ensure_no_nuls(dir)).encode_wide().collect();
  dir_str.push(0);
- (dir_str.as_ptr(), dir_str)
+ Ok((dir_str.as_ptr(), dir_str))
  },
- None => (ptr::null(), Vec::new())
+ None => Ok((ptr::null(), Vec::new()))
  }
 }
 
@@ -397,11 +419,12 @@ mod tests {
  #[test]
  fn test_make_command_line() {
  fn test_wrapper(prog: &str, args: &[&str]) -> String {
- String::from_utf16(
- &make_command_line(OsStr::new(prog),
- &args.iter()
- .map(|a| OsString::from(a))
- .collect::<Vec<OsString>>())).unwrap()
+ let command_line = &make_command_line(OsStr::new(prog),
+ &args.iter()
+ .map(|a| OsString::from(a))
+ .collect::<Vec<OsString>>())
+ .unwrap();
+ String::from_utf16(command_line).unwrap()
  }
 
  assert_eq!(