linux/arch/um/kernel/exec.c
Eric W. Biederman c200e4bb44 ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP
User mode linux is the last user of the PT_DTRACE flag.  Using the flag to indicate
single stepping is a little confusing and worse changing tsk->ptrace without locking
could potentionally cause problems.

So use a thread info flag with a better name instead of flag in tsk->ptrace.

Remove the definition PT_DTRACE as uml is the last user.

Cc: stable@vger.kernel.org
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lkml.kernel.org/r/20220505182645.497868-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-05-11 14:33:33 -05:00

52 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
*/
#include <linux/stddef.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/ptrace.h>
#include <linux/sched/mm.h>
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <linux/slab.h>
#include <asm/current.h>
#include <asm/processor.h>
#include <linux/uaccess.h>
#include <as-layout.h>
#include <mem_user.h>
#include <registers.h>
#include <skas.h>
#include <os.h>
void flush_thread(void)
{
void *data = NULL;
int ret;
arch_flush_thread(&current->thread.arch);
ret = unmap(&current->mm->context.id, 0, TASK_SIZE, 1, &data);
if (ret) {
printk(KERN_ERR "flush_thread - clearing address space failed, "
"err = %d\n", ret);
force_sig(SIGKILL);
}
get_safe_registers(current_pt_regs()->regs.gp,
current_pt_regs()->regs.fp);
__switch_mm(&current->mm->context.id);
}
void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp)
{
PT_REGS_IP(regs) = eip;
PT_REGS_SP(regs) = esp;
clear_thread_flag(TIF_SINGLESTEP);
#ifdef SUBARCH_EXECVE1
SUBARCH_EXECVE1(regs->regs);
#endif
}
EXPORT_SYMBOL(start_thread);