1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
* Stack protector support for NOLIBC
* Copyright (C) 2023 Thomas Weißschuh <linux@weissschuh.net>
*/
#ifndef _NOLIBC_STACKPROTECTOR_H
#define _NOLIBC_STACKPROTECTOR_H
#include "arch.h"
#if defined(NOLIBC_STACKPROTECTOR)
#if !defined(__ARCH_SUPPORTS_STACK_PROTECTOR)
#error "nolibc does not support stack protectors on this arch"
#endif
#include "sys.h"
#include "stdlib.h"
/* The functions in this header are using raw syscall macros to avoid
* triggering stack protector errors themselves
*/
__attribute__((weak,noreturn,section(".text.nolibc_stack_chk")))
void __stack_chk_fail(void)
{
pid_t pid;
my_syscall3(__NR_write, STDERR_FILENO, "!!Stack smashing detected!!\n", 28);
pid = my_syscall0(__NR_getpid);
my_syscall2(__NR_kill, pid, SIGABRT);
for (;;);
}
__attribute__((weak,noreturn,section(".text.nolibc_stack_chk")))
void __stack_chk_fail_local(void)
{
__stack_chk_fail();
}
__attribute__((weak,section(".data.nolibc_stack_chk")))
uintptr_t __stack_chk_guard;
__attribute__((weak,no_stack_protector,section(".text.nolibc_stack_chk")))
void __stack_chk_init(void)
{
my_syscall3(__NR_getrandom, &__stack_chk_guard, sizeof(__stack_chk_guard), 0);
/* a bit more randomness in case getrandom() fails */
__stack_chk_guard ^= (uintptr_t) &__stack_chk_guard;
}
#endif // defined(NOLIBC_STACKPROTECTOR)
#endif // _NOLIBC_STACKPROTECTOR_H
|
