From f42daea4c358f8d67934981f31b44bac34e20df2 Mon Sep 17 00:00:00 2001 From: Alex Crichton Date: Tue, 13 Nov 2018 14:50:50 -0800 Subject: [PATCH] Revert "Fixes #46775 -- don't mutate the process's environment in Command::exec" This reverts commit 36fe3b605a7a7143a14565272140ba1b43c1b041. --- src/libstd/sys/unix/process/process_common.rs | 8 -- src/libstd/sys/unix/process/process_unix.rs | 99 ++----------------- src/test/run-pass/command-exec.rs | 12 --- 3 files changed, 8 insertions(+), 111 deletions(-) diff --git a/src/libstd/sys/unix/process/process_common.rs b/src/libstd/sys/unix/process/process_common.rs index 3d5920dfb69ac..77f125f3c5b56 100644 --- a/src/libstd/sys/unix/process/process_common.rs +++ b/src/libstd/sys/unix/process/process_common.rs @@ -141,10 +141,6 @@ impl Command { pub fn get_argv(&self) -> &Vec<*const c_char> { &self.argv.0 } - #[cfg(not(target_os = "fuchsia"))] - pub fn get_program(&self) -> &CString { - return &self.program; - } #[allow(dead_code)] pub fn get_cwd(&self) -> &Option { @@ -248,10 +244,6 @@ impl CStringArray { pub fn as_ptr(&self) -> *const *const c_char { self.ptrs.as_ptr() } - #[cfg(not(target_os = "fuchsia"))] - pub fn get_items(&self) -> &[CString] { - return &self.items; - } } fn construct_envp(env: BTreeMap, saw_nul: &mut bool) -> CStringArray { diff --git a/src/libstd/sys/unix/process/process_unix.rs b/src/libstd/sys/unix/process/process_unix.rs index f41bd2c20720a..7f1f9353c6d09 100644 --- a/src/libstd/sys/unix/process/process_unix.rs +++ b/src/libstd/sys/unix/process/process_unix.rs @@ -8,8 +8,6 @@ // option. This file may not be copied, modified, or distributed // except according to those terms. -use env; -use ffi::CString; use io::{self, Error, ErrorKind}; use libc::{self, c_int, gid_t, pid_t, uid_t}; use ptr; @@ -41,15 +39,13 @@ impl Command { return Ok((ret, ours)) } - let possible_paths = self.compute_possible_paths(envp.as_ref()); - let (input, output) = sys::pipe::anon_pipe()?; let pid = unsafe { match cvt(libc::fork())? { 0 => { drop(input); - let err = self.do_exec(theirs, envp.as_ref(), possible_paths); + let err = self.do_exec(theirs, envp.as_ref()); let errno = err.raw_os_error().unwrap_or(libc::EINVAL) as u32; let bytes = [ (errno >> 24) as u8, @@ -117,48 +113,12 @@ impl Command { "nul byte found in provided data") } - let possible_paths = self.compute_possible_paths(envp.as_ref()); match self.setup_io(default, true) { - Ok((_, theirs)) => unsafe { self.do_exec(theirs, envp.as_ref(), possible_paths) }, + Ok((_, theirs)) => unsafe { self.do_exec(theirs, envp.as_ref()) }, Err(e) => e, } } - fn compute_possible_paths(&self, maybe_envp: Option<&CStringArray>) -> Option> { - let program = self.get_program().as_bytes(); - if program.contains(&b'/') { - return None; - } - // Outside the match so we can borrow it for the lifetime of the function. - let parent_path = env::var("PATH").ok(); - let paths = match maybe_envp { - Some(envp) => { - match envp.get_items().iter().find(|var| var.as_bytes().starts_with(b"PATH=")) { - Some(p) => &p.as_bytes()[5..], - None => return None, - } - }, - // maybe_envp is None if the process isn't changing the parent's env at all. - None => { - match parent_path.as_ref() { - Some(p) => p.as_bytes(), - None => return None, - } - }, - }; - - let mut possible_paths = vec![]; - for path in paths.split(|p| *p == b':') { - let mut binary_path = Vec::with_capacity(program.len() + path.len() + 1); - binary_path.extend_from_slice(path); - binary_path.push(b'/'); - binary_path.extend_from_slice(program); - let c_binary_path = CString::new(binary_path).unwrap(); - possible_paths.push(c_binary_path); - } - return Some(possible_paths); - } - // 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 @@ -192,8 +152,7 @@ impl Command { unsafe fn do_exec( &mut self, stdio: ChildPipes, - maybe_envp: Option<&CStringArray>, - maybe_possible_paths: Option>, + maybe_envp: Option<&CStringArray> ) -> io::Error { use sys::{self, cvt_r}; @@ -234,6 +193,9 @@ impl Command { if let Some(ref cwd) = *self.get_cwd() { t!(cvt(libc::chdir(cwd.as_ptr()))); } + if let Some(envp) = maybe_envp { + *sys::os::environ() = envp.as_ptr(); + } // emscripten has no signal support. #[cfg(not(any(target_os = "emscripten")))] @@ -269,53 +231,8 @@ impl Command { t!(callback()); } - // If the program isn't an absolute path, and our environment contains a PATH var, then we - // implement the PATH traversal ourselves so that it honors the child's PATH instead of the - // parent's. This mirrors the logic that exists in glibc's execvpe, except using the - // child's env to fetch PATH. - match maybe_possible_paths { - Some(possible_paths) => { - let mut pending_error = None; - for path in possible_paths { - libc::execve( - path.as_ptr(), - self.get_argv().as_ptr(), - maybe_envp.map(|envp| envp.as_ptr()).unwrap_or_else(|| *sys::os::environ()) - ); - let err = io::Error::last_os_error(); - match err.kind() { - io::ErrorKind::PermissionDenied => { - // If we saw a PermissionDenied, and none of the other entries in - // $PATH are successful, then we'll return the first EACCESS we see. - if pending_error.is_none() { - pending_error = Some(err); - } - }, - // Errors which indicate we failed to find a file are ignored and we try - // the next entry in the path. - io::ErrorKind::NotFound | io::ErrorKind::TimedOut => { - continue - }, - // Any other error means we found a file and couldn't execute it. - _ => { - return err; - } - } - } - if let Some(err) = pending_error { - return err; - } - return io::Error::from_raw_os_error(libc::ENOENT); - }, - _ => { - libc::execve( - self.get_argv()[0], - self.get_argv().as_ptr(), - maybe_envp.map(|envp| envp.as_ptr()).unwrap_or_else(|| *sys::os::environ()) - ); - return io::Error::last_os_error() - } - } + libc::execvp(self.get_argv()[0], self.get_argv().as_ptr()); + io::Error::last_os_error() } #[cfg(not(any(target_os = "macos", target_os = "freebsd", diff --git a/src/test/run-pass/command-exec.rs b/src/test/run-pass/command-exec.rs index 96f9da67790fc..46b409fb13a84 100644 --- a/src/test/run-pass/command-exec.rs +++ b/src/test/run-pass/command-exec.rs @@ -48,13 +48,6 @@ fn main() { println!("passed"); } - "exec-test5" => { - env::set_var("VARIABLE", "ABC"); - Command::new("definitely-not-a-real-binary").env("VARIABLE", "XYZ").exec(); - assert_eq!(env::var("VARIABLE").unwrap(), "ABC"); - println!("passed"); - } - _ => panic!("unknown argument: {}", arg), } return @@ -79,9 +72,4 @@ fn main() { assert!(output.status.success()); assert!(output.stderr.is_empty()); assert_eq!(output.stdout, b"passed\n"); - - let output = Command::new(&me).arg("exec-test5").output().unwrap(); - assert!(output.status.success()); - assert!(output.stderr.is_empty()); - assert_eq!(output.stdout, b"passed\n"); }