xref: /linux-6.15/arch/um/kernel/exec.c (revision 42459792)
1 /*
2  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3  * Licensed under the GPL
4  */
5 
6 #include <linux/stddef.h>
7 #include <linux/module.h>
8 #include <linux/fs.h>
9 #include <linux/ptrace.h>
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <asm/current.h>
13 #include <asm/processor.h>
14 #include <asm/uaccess.h>
15 #include "as-layout.h"
16 #include "mem_user.h"
17 #include "skas.h"
18 #include "os.h"
19 #include "internal.h"
20 
21 void flush_thread(void)
22 {
23 	void *data = NULL;
24 	int ret;
25 
26 	arch_flush_thread(&current->thread.arch);
27 
28 	ret = unmap(&current->mm->context.id, 0, STUB_START, 0, &data);
29 	ret = ret || unmap(&current->mm->context.id, STUB_END,
30 			   host_task_size - STUB_END, 1, &data);
31 	if (ret) {
32 		printk(KERN_ERR "flush_thread - clearing address space failed, "
33 		       "err = %d\n", ret);
34 		force_sig(SIGKILL, current);
35 	}
36 
37 	__switch_mm(&current->mm->context.id);
38 }
39 
40 void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp)
41 {
42 	PT_REGS_IP(regs) = eip;
43 	PT_REGS_SP(regs) = esp;
44 	current->ptrace &= ~PT_DTRACE;
45 #ifdef SUBARCH_EXECVE1
46 	SUBARCH_EXECVE1(regs->regs);
47 #endif
48 }
49 EXPORT_SYMBOL(start_thread);
50 
51 long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env)
52 {
53 	long err;
54 
55 	err = do_execve(file, argv, env, &current->thread.regs);
56 	if (!err)
57 		UML_LONGJMP(current->thread.exec_buf, 1);
58 	return err;
59 }
60 
61 long sys_execve(const char __user *file, const char __user *const __user *argv,
62 		const char __user *const __user *env)
63 {
64 	long error;
65 	char *filename;
66 
67 	filename = getname(file);
68 	error = PTR_ERR(filename);
69 	if (IS_ERR(filename)) goto out;
70 	error = do_execve(filename, argv, env, &current->thread.regs);
71 	putname(filename);
72  out:
73 	return error;
74 }
75