mirror of
https://github.com/RGBCube/serenity
synced 2025-07-26 06:47:34 +00:00
Kernel: Make ProcessGroup a ListedRefCounted and fix two races
This closes two race windows: - ProcessGroup removed itself from the "all process groups" list in its destructor. It was possible to walk the list between the last unref() and the destructor invocation, and grab a pointer to a ProcessGroup that was about to get deleted. - sys$setsid() could end up creating a process group that already existed, as there was a race window between checking if the PGID is used, and actually creating a ProcessGroup with that PGID.
This commit is contained in:
parent
37bfc36601
commit
3e30d9bc99
3 changed files with 29 additions and 36 deletions
|
@ -1,15 +1,15 @@
|
|||
/*
|
||||
* Copyright (c) 2020, the SerenityOS developers.
|
||||
* Copyright (c) 2020-2023, the SerenityOS developers.
|
||||
*
|
||||
* SPDX-License-Identifier: BSD-2-Clause
|
||||
*/
|
||||
|
||||
#pragma once
|
||||
|
||||
#include <AK/AtomicRefCounted.h>
|
||||
#include <AK/IntrusiveList.h>
|
||||
#include <AK/RefPtr.h>
|
||||
#include <Kernel/Forward.h>
|
||||
#include <Kernel/Library/ListedRefCounted.h>
|
||||
#include <Kernel/Library/LockWeakable.h>
|
||||
#include <Kernel/Locking/SpinlockProtected.h>
|
||||
#include <Kernel/UnixTypes.h>
|
||||
|
@ -17,7 +17,7 @@
|
|||
namespace Kernel {
|
||||
|
||||
class ProcessGroup
|
||||
: public AtomicRefCounted<ProcessGroup>
|
||||
: public ListedRefCounted<ProcessGroup, LockType::Spinlock>
|
||||
, public LockWeakable<ProcessGroup> {
|
||||
|
||||
AK_MAKE_NONMOVABLE(ProcessGroup);
|
||||
|
@ -26,7 +26,7 @@ class ProcessGroup
|
|||
public:
|
||||
~ProcessGroup();
|
||||
|
||||
static ErrorOr<NonnullRefPtr<ProcessGroup>> create(ProcessGroupID);
|
||||
static ErrorOr<NonnullRefPtr<ProcessGroup>> create_if_unused_pgid(ProcessGroupID);
|
||||
static ErrorOr<NonnullRefPtr<ProcessGroup>> find_or_create(ProcessGroupID);
|
||||
static RefPtr<ProcessGroup> from_pgid(ProcessGroupID);
|
||||
|
||||
|
@ -38,13 +38,13 @@ private:
|
|||
{
|
||||
}
|
||||
|
||||
IntrusiveListNode<ProcessGroup> m_list_node;
|
||||
ProcessGroupID m_pgid;
|
||||
|
||||
mutable IntrusiveListNode<ProcessGroup> m_list_node;
|
||||
|
||||
public:
|
||||
using List = IntrusiveList<&ProcessGroup::m_list_node>;
|
||||
using AllInstancesList = IntrusiveList<&ProcessGroup::m_list_node>;
|
||||
static SpinlockProtected<AllInstancesList, LockRank::None>& all_instances();
|
||||
};
|
||||
|
||||
SpinlockProtected<ProcessGroup::List, LockRank::None>& process_groups();
|
||||
|
||||
}
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue