diff options
Diffstat (limited to 'library/std/src/sys/unix/process/process_unix.rs')
| -rw-r--r-- | library/std/src/sys/unix/process/process_unix.rs | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/library/std/src/sys/unix/process/process_unix.rs b/library/std/src/sys/unix/process/process_unix.rs index 99013efb495..326382d9038 100644 --- a/library/std/src/sys/unix/process/process_unix.rs +++ b/library/std/src/sys/unix/process/process_unix.rs @@ -166,6 +166,12 @@ impl Command { fn clone3(cl_args: *mut clone_args, len: libc::size_t) -> libc::c_long } + // Bypassing libc for `clone3` can make further libc calls unsafe, + // so we use it sparingly for now. See #89522 for details. + // Some tools (e.g. sandboxing tools) may also expect `fork` + // rather than `clone3`. + let want_clone3_pidfd = self.get_create_pidfd(); + // If we fail to create a pidfd for any reason, this will // stay as -1, which indicates an error. let mut pidfd: pid_t = -1; @@ -173,14 +179,9 @@ impl Command { // Attempt to use the `clone3` syscall, which supports more arguments // (in particular, the ability to create a pidfd). If this fails, // we will fall through this block to a call to `fork()` - if HAS_CLONE3.load(Ordering::Relaxed) { - let mut flags = 0; - if self.get_create_pidfd() { - flags |= CLONE_PIDFD; - } - + if want_clone3_pidfd && HAS_CLONE3.load(Ordering::Relaxed) { let mut args = clone_args { - flags, + flags: CLONE_PIDFD, pidfd: &mut pidfd as *mut pid_t as u64, child_tid: 0, parent_tid: 0, @@ -212,8 +213,8 @@ impl Command { } } - // If we get here, the 'clone3' syscall does not exist - // or we do not have permission to call it + // Generally, we just call `fork`. If we get here after wanting `clone3`, + // then the syscall does not exist or we do not have permission to call it. cvt(libc::fork()).map(|res| (res, pidfd)) } |