File: minimal_runtime.h

package info (click to toggle)
llvm-toolchain-17 1%3A17.0.6-22
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 1,799,624 kB
  • sloc: cpp: 6,428,607; ansic: 1,383,196; asm: 793,408; python: 223,504; objc: 75,364; f90: 60,502; lisp: 33,869; pascal: 15,282; sh: 9,684; perl: 7,453; ml: 4,937; awk: 3,523; makefile: 2,889; javascript: 2,149; xml: 888; fortran: 619; cs: 573
file content (36 lines) | stat: -rw-r--r-- 982 bytes parent folder | download | duplicates (32) 
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
 
// A shadow call stack runtime is not yet included with compiler-rt, provide a
// minimal runtime to allocate a shadow call stack and assign an
// architecture-specific register to point at it.

#pragma once

#include <stdlib.h>
#include <sys/mman.h>
#include <sys/prctl.h>

#include "libc_support.h"

__attribute__((no_sanitize("shadow-call-stack")))
static void __shadowcallstack_init() {
  void *stack = mmap(NULL, 8192, PROT_READ | PROT_WRITE,
                     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  if (stack == MAP_FAILED)
    abort();

#if defined(__aarch64__)
  __asm__ __volatile__("mov x18, %0" ::"r"(stack));
#else
#error Unsupported platform
#endif
}

int scs_main(void);

__attribute__((no_sanitize("shadow-call-stack"))) int main(void) {
  __shadowcallstack_init();

  // We can't simply return scs_main() because scs_main might have corrupted our
  // return address for testing purposes (see overflow.c), so we need to exit
  // ourselves.
  exit(scs_main());
}