Files
asterinas/kernel/src/syscall/clone.rs
Carlos López 0a36760f7a Respect user-defined exit signal in clone() and clone3()
When calling clone() and clone3(), the user is allowed to specify a
signal to be sent to the parent process on exit. Respect this value by
storing it in the Process struct and sending the signal on exit.

Add a test as well to verify that the signal is properly delivered to
the parent.
2024-09-26 20:07:43 +08:00

114 lines
3.4 KiB
Rust

// SPDX-License-Identifier: MPL-2.0
use core::num::NonZeroU64;
use ostd::cpu::UserContext;
use super::SyscallReturn;
use crate::{
prelude::*,
process::{clone_child, signal::sig_num::SigNum, CloneArgs, CloneFlags},
};
// The order of arguments for clone differs in different architecture.
// This order we use here is the order for x86_64. See https://man7.org/linux/man-pages/man2/clone.2.html.
pub fn sys_clone(
clone_flags: u64,
new_sp: u64,
parent_tidptr: Vaddr,
child_tidptr: Vaddr,
tls: u64,
ctx: &Context,
parent_context: &UserContext,
) -> Result<SyscallReturn> {
let args = CloneArgs::for_clone(clone_flags, parent_tidptr, child_tidptr, tls, new_sp)?;
debug!("flags = {:?}, child_stack_ptr = 0x{:x}, parent_tid_ptr = 0x{:x?}, child tid ptr = 0x{:x}, tls = 0x{:x}", args.flags, args.stack, args.parent_tid, args.child_tid, args.tls);
let child_pid = clone_child(ctx, parent_context, args).unwrap();
Ok(SyscallReturn::Return(child_pid as _))
}
pub fn sys_clone3(
clong_args_addr: Vaddr,
size: usize,
ctx: &Context,
parent_context: &UserContext,
) -> Result<SyscallReturn> {
trace!(
"clone args addr = 0x{:x}, size = 0x{:x}",
clong_args_addr,
size
);
if size != core::mem::size_of::<Clone3Args>() {
return_errno_with_message!(Errno::EINVAL, "invalid size");
}
let clone_args = {
let args: Clone3Args = ctx.get_user_space().read_val(clong_args_addr)?;
trace!("clone3 args = {:x?}", args);
CloneArgs::from(args)
};
debug!("clone args = {:x?}", clone_args);
let child_pid = clone_child(ctx, parent_context, clone_args)?;
trace!("child pid = {}", child_pid);
Ok(SyscallReturn::Return(child_pid as _))
}
#[repr(C)]
#[derive(Debug, Clone, Copy, Pod)]
struct Clone3Args {
/// Flags bit mask
flags: u64,
/// Where to store PID file descriptor
pidfd: u64,
/// Where to store child TID in child's memory
child_tid: u64,
/// Where to store child TID in parent's memory
parent_tid: u64,
/// Signal to deliver to parent on child termination
exit_signal: u64,
/// Pointer to lowest byte of stack
stack: u64,
/// Size of stack
stack_size: u64,
/// Location of new TLS
tls: u64,
/// Pointer to a pid_t array
set_tid: u64,
/// Number of elements in set_tid
set_tid_size: u64,
/// File descriptor for target cgroup of child
cgroup: u64,
}
impl From<Clone3Args> for CloneArgs {
fn from(value: Clone3Args) -> Self {
// TODO: deal with pidfd, set_tid, set_tid_size, cgroup
if value.pidfd != 0 {
warn!("pidfd is not supported");
}
if value.set_tid != 0 || value.set_tid_size != 0 {
warn!("set_tid is not supported");
}
if value.cgroup != 0 {
warn!("cgroup is not supported");
}
Self {
flags: CloneFlags::from_bits_truncate(value.flags as u32),
_pidfd: Some(value.pidfd),
child_tid: value.child_tid as _,
parent_tid: Some(value.parent_tid as _),
exit_signal: (value.exit_signal != 0).then(|| SigNum::from_u8(value.exit_signal as u8)),
stack: value.stack,
stack_size: NonZeroU64::new(value.stack_size),
tls: value.tls,
_set_tid: Some(value.set_tid),
_set_tid_size: Some(value.set_tid_size),
_cgroup: Some(value.cgroup),
}
}
}