vasilito/RedBear-OS
1
0
Fork 0
Code Issues Pull Requests Actions 16 Packages Projects Releases Wiki Activity

Fix thread cleanup during active file ops.

Browse Source 
This fixes a bug where the window of `viewer` does not exit, due to a
leaked file descriptor.
This commit is contained in:
4lDO2
2024-07-20 22:14:54 +02:00
parent 29170ccbc7
commit 005635083d
5 changed files with 93 additions and 74 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/context/process.rs
+1
View File
@@ -73,6 +73,7 @@ impl DerefMut for Process {
pub enum ProcessStatus {
PossiblyRunnable,
Stopped(usize),
Exiting,
Exited(usize),
}
src/context/signal.rs
+7 -3
View File
@@ -7,10 +7,14 @@ use crate::{
pub fn signal_handler() {
let context_lock = context::current();
let mut context = context_lock.write();
let context = &mut *context;
let mut context_guard = context_lock.write();
let context = &mut *context_guard;
if context.being_sigkilled {
let being_sigkilled = context.being_sigkilled;
if being_sigkilled {
drop(context_guard);
drop(context_lock);
crate::syscall::process::exit(SIGKILL << 8);
}
src/scheme/pipe.rs
-1
View File
@@ -217,7 +217,6 @@ impl KernelScheme for PipeScheme {
return Err(Error::new(EPIPE));
}
let bytes_left = MAX_QUEUE_SIZE.saturating_sub(vec.len());
let bytes_to_write = core::cmp::min(bytes_left, user_buf.len());
let src_buf = user_buf
src/scheme/proc.rs
+3 -3
View File
@@ -1441,10 +1441,10 @@ impl ContextHandle {
}
}
crate::syscall::exit_context(context);
if is_current {
context::switch();
crate::syscall::exit_this_context();
} else {
crate::syscall::wait_for_exit(context);
}
Ok(mem::size_of::<usize>())
src/syscall/process.rs
+82 -67
View File
@@ -29,17 +29,11 @@ use crate::{
use super::usercopy::UserSliceWo;
pub fn exit_context(context_lock: Arc<RwSpinlock<Context>>) {
if !context::is_current(&context_lock) {
context_lock.write().status = context::Status::Dead;
while context_lock.read().running {
context::switch();
}
}
pub fn exit_this_context() -> ! {
let close_files;
let addrspace_opt;
let context_lock = context::current();
{
let mut context = context_lock.write();
close_files = Arc::try_unwrap(mem::take(&mut context.files))
@@ -61,81 +55,103 @@ pub fn exit_context(context_lock: Arc<RwSpinlock<Context>>) {
// TODO: Should status == Status::HardBlocked be handled differently?
context_lock.write().status = context::Status::Dead;
let _ = context::contexts_mut().remove(&ContextRef(context_lock));
context::switch();
unreachable!();
}
pub fn wait_for_exit(context_lock: Arc<RwSpinlock<Context>>) {
{
let mut ctxt = context_lock.write();
ctxt.status = context::Status::Runnable;
ctxt.being_sigkilled = true;
}
while !matches!(context_lock.read().status, context::Status::Dead) {
context::switch();
}
}
pub fn exit(status: usize) -> ! {
if matches!(
mem::replace(
&mut process::current().unwrap().write().status,
ProcessStatus::Exiting
),
ProcessStatus::Exiting
) {
// already exiting the current process, so just set our status to Dead and context switch.
exit_this_context();
}
ptrace::breakpoint_callback(
PTRACE_STOP_EXIT,
Some(ptrace_event!(PTRACE_STOP_EXIT, status)),
);
let current_context = context::current();
let current_process = process::current().expect("no active process during exit syscall");
let current_pid = current_process.read().pid;
let threads = core::mem::take(&mut current_process.write().threads);
for context_lock in threads.into_iter().filter_map(|t| t.upgrade()) {
// Current context must be closed last, as it would otherwise be impossible to context
// switch back, if closing file descriptors require scheme calls.
if Arc::ptr_eq(&context_lock, &current_context) {
continue;
}
exit_context(context_lock);
}
exit_context(current_context);
{
// PGID and PPID must be grabbed after close, as context switches could change PGID or PPID if parent exits
let (pgid, ppid) = {
let process = current_process.read();
(process.pgid, process.ppid)
};
if let Some(parent) = process::PROCESSES.read().get(&ppid).map(Arc::clone) {
let _ = send_signal(KillTarget::Process(parent), SIGCHLD, true, &mut false);
}
let current_context = context::current();
let current_process = process::current().expect("no active process during exit syscall");
let current_pid = current_process.read().pid;
// Transfer child processes to parent (TODO: to init)
{
let processes = context::process::PROCESSES.read();
for (_child_pid, child_process_lock) in processes.iter() {
let mut process = child_process_lock.write();
if process.ppid == current_pid {
process.ppid = ppid;
}
let threads = core::mem::take(&mut current_process.write().threads);
for context_lock in threads.into_iter().filter_map(|t| t.upgrade()) {
// Current context must be closed last, as it would otherwise be impossible to context
// switch back, if closing file descriptors require scheme calls.
if Arc::ptr_eq(&context_lock, &current_context) {
continue;
}
wait_for_exit(context_lock);
}
current_process.write().status = ProcessStatus::Exited(status);
let children = current_process.write().waitpid.receive_all();
{
let processes = process::PROCESSES.read();
if let Some(parent_lock) = processes.get(&ppid) {
let waitpid = Arc::clone(&parent_lock.write().waitpid);
for (c_pid, c_status) in children {
waitpid.send(c_pid, c_status);
}
waitpid.send(
WaitpidKey {
pid: Some(current_pid),
pgid: Some(pgid),
},
(current_pid, status),
);
// PGID and PPID must be grabbed after close, as context switches could change PGID or PPID if parent exits
let (pgid, ppid) = {
let process = current_process.read();
(process.pgid, process.ppid)
};
if let Some(parent) = process::PROCESSES.read().get(&ppid).map(Arc::clone) {
let _ = send_signal(KillTarget::Process(parent), SIGCHLD, true, &mut false);
}
}
// Alert any tracers waiting of this process
ptrace::close_tracee(current_pid);
// Transfer child processes to parent (TODO: to init)
{
let processes = context::process::PROCESSES.read();
for (_child_pid, child_process_lock) in processes.iter() {
let mut process = child_process_lock.write();
if process.ppid == current_pid {
process.ppid = ppid;
}
}
}
current_process.write().status = ProcessStatus::Exited(status);
let children = current_process.write().waitpid.receive_all();
{
let processes = process::PROCESSES.read();
if let Some(parent_lock) = processes.get(&ppid) {
let waitpid = Arc::clone(&parent_lock.write().waitpid);
for (c_pid, c_status) in children {
waitpid.send(c_pid, c_status);
}
waitpid.send(
WaitpidKey {
pid: Some(current_pid),
pgid: Some(pgid),
},
(current_pid, status),
);
}
}
// Alert any tracers waiting of this process
ptrace::close_tracee(current_pid);
}
}
let _ = context::switch();
unreachable!();
exit_this_context();
}
pub fn getpid() -> Result<ProcessId> {
@@ -298,7 +314,6 @@ pub fn send_signal(
context_guard.being_sigkilled = true;
context_guard.unblock();
drop(context_guard);
process_lock.write().status = ProcessStatus::Exited(SIGKILL);
*killed_self |= is_self;
// exit() will signal the parent, rather than immediately in kill()