// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/kernel/ptrace.c
*
* (C) Copyright 1999 Linus Torvalds
*
* Common interfaces for "ptrace()" which we do not want
* to continually duplicate across every architecture.
*/
#include <linux/capability.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/sched/coredump.h>
#include <linux/sched/task.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/ptrace.h>
#include <linux/security.h>
#include <linux/signal.h>
#include <linux/uio.h>
#include <linux/audit.h>
#include <linux/pid_namespace.h>
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/regset.h>
#include <linux/hw_breakpoint.h>
#include <linux/cn_proc.h>
#include <linux/compat.h>
#include <linux/sched/signal.h>
/*
* Access another process' address space via ptrace.
* Source/target buffer must be kernel space,
* Do not walk the page table directly, use get_user_pages
*/
int ptrace_access_vm(struct task_struct *tsk, unsigned long addr,
void *buf, int len, unsigned int gup_flags)
{
struct mm_struct *mm;
int ret;
mm = get_task_mm(tsk);
if (!mm)
return 0;
if (!tsk->ptrace ||
(current != tsk->parent) ||
((get_dumpable(mm) != SUID_DUMP_USER) &&
!ptracer_capable(tsk, mm->user_ns))) {
mmput(mm);
return 0;
}
ret = __access_remote_vm(tsk, mm, addr, buf, len, gup_flags);
mmput(mm);
return ret;
}
void __ptrace_link(struct task_struct *child, struct task_struct *new_parent,
const struct cred *ptracer_cred)
{
BUG_ON(!list_empty(&child->ptrace_entry));
list_add(&child->ptrace_entry, &new_parent->ptraced);
child->parent = new_parent;
child->ptracer_cred = get_cred(ptracer_cred);
}
/*
* ptrace a task: make the debugger its new parent and
* move it to the ptrace list.
*
* Must be called with the tasklist lock write-held.
*/
static void ptrace_link(struct task_struct *child, struct task_struct *new_parent)
{
__ptrace_link(child, new_parent, current_cred());
}
/**
* __ptrace_unlink - unlink ptracee and restore its execution stat